Journal articles: 'TIG-2'

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Kumar, Sujeet, and Anil Kumar Das. "Evaluation of mechanical properties of TiB₂-TiO₂ ceramic composite coating on AISI 1020 mild steel by TIG cladding." Engineering Research Express 4, no. 1 (March 1, 2022): 015034. http://dx.doi.org/10.1088/2631-8695/ac5ae7.

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Abstract The main objective of the present work was to enhance the mechanical properties of AISI 1020 steel by depositing the TiB2-TiO2 composite coating on it with the help of the tungsten inert gas (TIG) cladding process. The semi-solid mixture of 50 wt% of TiB2 and 50 wt% of TiO2 was preplaced on AISI 1020 steel and a TIG torch was used as heat source to melt the preplaced layer as well as substrate layer to produce the new coating layer. Characteristics of the cladded layer were examined using Vickers microhardness tester, energy dispersive spectroscopy (EDS), scanning electron microscope (SEM) and x-ray diffractometer (XRD). The TIG currents have shown a significant influence on the microstructure and mechanical properties of the coated layer. Metallography result also shows that the input current of the TIG cladding has considerable effect on the microstructure and quality of the coating. Microstructural changes in the clad layer were studied in detail. The Vickers micro-hardness value of the coated layer increases with decrease in input current and maximum microhardness was achieved about 568 HV0.05 which was about 3.5 times higher than that of the substrate (157 HV0.05). The dry sliding abrasive wear test was performed against EN31 hardened alloy steel as counter body by pin-on-disc tribometer with sliding distance of 1036 meters. The coating produced at lower TIG current (110 A) exhibits minimum average wear rate 1.46 × 10−6 g N−1m−1 while coating processed at higher TIG current (155 A) exhibits higher average wear rate 2.18 × 10−6 g N−1m−1. It was also concluded that the wear rate of the TiB2-TiO2 coating decreases with decreasing processing current and minimum wear rate (1.46 × 10−6 g N−1m−1) obtained up to 2.5 times lower as compare to wear of AISI 1020 mild steel substrate (3.65 × 10−6 g N−1m−1) which makes the TiB2-TiO2 coating suitable for application as wear resistance components. The average coefficient of friction also decreases with increasing TIG current and found maximum (0.76) and minimum (0.58) for the coating deposited at 110 A and 155 A current, respectively.

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Patel, Dixit, Suketu Jani, and Darshit Shah. "Effect of Oxide Flux Particle Size on Weld Bead Morphology of Hastelloy C-22." Jurnal Kejuruteraan 34, no. 6 (November 30, 2022): 1077–83. http://dx.doi.org/10.17576/jkukm-2022-34(6)-08.

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Activated tungsten inert gas welding (ATIG) welding is a new approach to Tungsten Inert Gas (TIG) welding that has the potential to improve weld penetration. This paper investigates the effect of micro and nanoparticle size oxide flux during TIG welding of Hastelloy C-22. The effect of SiO2 and Al2O3 oxide fluxes in terms of particle size and thermal stability on surface appearance, bead geometry, and microhardness of the fusion zone of hastelloy C-22 is investigated. The surface appearance of ATIG weld has a better appearance using nanoparticle size oxide flux when compared with the same micro size oxide flux. A slag layer produced by nano flux decomposition during TIG welding is very less compared to micro oxide fluxes. Nanoparticle SiO2 flux has the potential to improve weld penetration and depth to width (D/W) ratio in the generated weldment when compared to microparticle SiO2 flux during TIG welding Process. When nanoparticle Al2O3 is used in TIG welding, weld penetration or the D/W ratio do not increase significantly. Due to the high voltage produced at the same arc length, TIG welding with nanoparticle SiO2 flux produces a high heat input. Furthermore, higher arc temperatures produce by nanoparticle fluxes at the arc column, resulting in increased penetration depth.

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Sönmez, Murat, and Polat Topuz. "Effect of TIG welding parameters in joining grade 2 pure titanium." Materials Testing 63, no. 5 (May 1, 2021): 420–25. http://dx.doi.org/10.1515/mt-2020-0071.

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Abstract Grade 2, the most widely used pure titanium in the industry, has high corrosion resistance, excellent ductility, good weldability and is easily machinable. If titanium is exposed to temperatures above 500 °C due to moisture or hydrocarbons in the air, it is susceptible to taking up oxygen, nitrogen, carbon and hydrogen. This can cause cracks, especially after welding. Therefore, protection of the welding zone from external factors is of great importance during welding. For these reasons, TIG welding is the most widely used method for titanium welding. In this study, Grade 2 pure titanium plates are joined by TIG welding at three (40 A, 60 A and 80 A) current values under the same conditions. For the welding process, 2 wt.-% cerium addition Tungsten tip and high purity (99.99 vol.-%) argon was used as a shielding gas. After a visual inspection of the welded samples, microstructure inspections, macrostructure inspections, hardness measurements, bending tests and tensile tests were performed in accordance with the standards. As a result of the investigations, it was determined that the most suitable current value for the joining of Grade 2 titanium by TIG welding was 60 A.

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Wang, Junhui, Zhijun Wan, Hongwei Zhang, Dong Wu, Yuan Zhang, Yi Wang, Luchang Xiong, and Guoli Wang. "Application of Thermal Insulation Gunite Material to the High Geo-Temperature Roadway." Advances in Civil Engineering 2020 (August 19, 2020): 1–12. http://dx.doi.org/10.1155/2020/8853870.

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Thermal insulation gunite (TIG) in roadways is an effective method for regional thermal hazard control in mines. The development of mine TIG materials is the foundation of thermal insulation technique. However, some conventional and advanced insulation materials are inapplicable to deep mines which are rather humid with high in situ stress and high geo-temperature. In this study, a kind of fly ash-inorganic mineral TIG material was developed and applied to the modelling of a high geo-temperature roadway. Moreover, the thermal insulation effect of the TIG layer was analyzed, and the temperature field characteristics of the TIG surrounding rock were discussed. Results reveal that (1) the TIG layer has a significant impact on the heat release of the wall and stability of the surrounding rock temperature field; (2) the initial temperature disturbance times, temperature disturbance ranges, and temperature drop rates differ with whether a TIG layer exists or not; (3) after the TIG roadway starts to be ventilated, the thermal flux densities tend to be consistent, which indicates the end of temperature disturbance; besides, the dimensionless temperature shares an exponential relation with the dimensionless radius; and (4) the characteristics of temperature drops vary with the radial positions of the surrounding rock. The research results provide a certain reference for thermal hazard control, temperature prediction, and ventilation network adjustment.

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Vaklavas, Christos, Vandana Gupta Abramson, Nancy U. Lin, Minetta C. Liu, Hope S. Rugo, Rita Nanda, Anna Maria Storniolo, et al. "TBCRC 019: An open label, randomized, phase II trial of nanoparticle albumin-bound paclitaxel (nab-PAC) with or without the anti-death receptor 5 (DR5) monoclonal antibody tigatuzumab (TIG) in patients with metastatic triple negative breast cancer (TNBC)." Journal of Clinical Oncology 31, no. 15_suppl (May 20, 2013): 1052. http://dx.doi.org/10.1200/jco.2013.31.15_suppl.1052.

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1052 Background: TIG, an agonistic anti-DR5 monoclonal antibody, triggers apoptosis in DR5+ human tumor cells without the aid of crosslinking. TIG has shown strong in vitro and in vivo activity against basal-like breast cancer cells that is enhanced by chemotherapy like paclitaxel. Methods: Randomized 2:1 phase II trial of nab-PAC with/without TIG in TNBC patients. Patients stratified by prior exposure to chemotherapy in the metastatic setting. Patients received nab-PAC weekly x 3 and TIG every other week, every 28 days. Primary endpoint was overall response rate (ORR). Secondary objectives were safety, progression free survival (PFS), TIG immunogenicity, and PK. Biopsies and circulating tumor cells were collected. The trial was not powered to compare arms but allowed early stopping for futility and was sized to estimate ORR with 95% CI. Results: 64 patients enrolled, 60 treated; 39 in the combination arm and 21 in the nab-PAC arm. Of the 39 in the combination arm, there were 2 CR, 9 PR (1 near CR, 96% tumor reduction), 11 SD and 17 PD; ORR 28% (95% CI 14%-42%). Of the 21 in the single agent arm, there were no CR, 8 PR, 4 SD and 9 PD; ORR 38% (95% CI 17%-59%). Higher ORRs were seen in the chemotherapy naïve patients (58% vs. 15% combination and 42% vs. 35% single agent). 2 patients with CR, 1 near CR, and 1 PR in the combination arm are still on therapy (602+, 531+, 466+, 460+ days). PFS was similar in both groups (3.6 months); higher in chemotherapy naïve patients. Combination was well tolerated (most toxicities grade 1/2); the most common AEs were fatigue, alopecia, peripheral sensory neuropathy, anemia, neutropenia, nausea, thrombocytopenia, anorexia, diarrhea, and vomiting. No grade 4 or 5 toxicity. No apparent added toxicity with TIG was seen. Conclusions: Combination therapy with nab-PAC + TIG was well tolerated, without apparent improvement in ORR relative to nab-PAC alone; however, 4 subjects treated as first-line had prolonged clinical benefit with the combination, and correlative studies will investigate markers that might predict clinical outcome (Next-Gen genomic analysis). Clinical trial information: F101004001.

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Cheniti, Billel, Djamel Miroud, Pavol Hvizdoš, Brahim Belkessa, Richard Sedlák, Naima Ouali, and Djilali Allou. "Comparative Study on the Microstructural and Mechanical Properties of WC-Co/AISI 1020 Steel Brazed Joint Obtained by TIG and Oxyacetylene Process." Diffusion Foundations 18 (September 2018): 41–48. http://dx.doi.org/10.4028/www.scientific.net/df.18.41.

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In this work, the microstructural evolution and the mechanical properties of WC-Co / AISI 1020 steel brazed joint obtained by oxyacetylene and Tungsten Inert Gas (TIG) brazing process are investigated. The maximum peak temperature induced by TIG process and the introduction of a shielding gas cause a remarkable diffusion of Co and rearrangement of WC particles along the interface with the filler alloy. The Energy Dispersive Spectroscopy (EDS) analysis reveals that the inter-diffusion activity of elements across the interfaces especially Co and Ni is more important using TIG process compared to oxyacetylene process The mechanical behavior is carried out through micro-hardness measurements and toughness tests using Vickers Indentation fracture method on the WC-Co along the parallel line of the interface with the filler alloy. The results show that the brazed joint issued from TIG process becomes increasingly hard and brittle when approaching the WC-Co/braze interface and loses its toughness (7 MPa/m1/2 compared to 15 MPA/m1/2 for oxyacetylene process) with increasing the brazing temperature.

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Sonar, Tushar, Visvalingam Balasubramanian, Sudersanan Malarvizhi, Thiruvenkatam Venkateswaran, and Dhenuvakonda Sivakumar. "Optimization of CA-TIG welding parameters to predict and maximize tensile properties of super alloy 718 sheets for gas turbine applications." Aircraft Engineering and Aerospace Technology 94, no. 5 (January 11, 2022): 806–23. http://dx.doi.org/10.1108/aeat-09-2020-0218.

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Purpose The primary objective of this investigation is to optimize the constricted arc tungsten inert gas (CA-TIG) welding parameters specifically welding current (WC), arc constriction current (ACC), ACC frequency (ACCF) and CA traverse speed to maximize the tensile properties of thin Inconel 718 sheets (2 mm thick) using a statistical technique of response surface methodology and desirability function for gas turbine engine applications. Design/methodology/approach The four factor – five level central composite design (4 × 5 – CCD) matrix pertaining to the minimum number of experiments was chosen in this investigation for designing the experimental matrix. The techniques of numerical and graphical optimization were used to find the optimal conditions of CA-TIG welding parameters. Findings The thin sheets of Inconel 718 (2 mm thick) can be welded successfully using CA-TIG welding process without any defects. The joints welded using optimized conditions of CA-TIG welding parameters showed maximum of 99.20%, 94.45% and 73.5% of base metal tensile strength, yield strength and elongation. Originality/value The joints made using optimized CA-TIG welding parameters disclosed 99.20% joint efficiency which is comparatively 20%–30% superior than conventional TIG welding process and comparable to costly electron beam welding and laser beam welding processes. The parametric mathematical equations were designed to predict the tensile properties of Inconel 718 joints accurately with a confidence level of 95% and less than 4.5% error. The mathematical relationships were also developed to predict the tensile properties of joints from the grain size (secondary dendritic arm spacing-SDAS) of fusion zone microstructure.

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Atoui, Juliana Abdallah, Daniela Nair Borges Felipucci, Valeria Oliveira Pagnano, Iara Augusta Orsi, Mauro Antonio de Arruda Nobilo, and Osvaldo Luiz Bezzon. "Tensile and Flexural Strength of Commercially Pure Titanium Submitted to Laser and Tungsten Inert Gas Welds." Brazilian Dental Journal 24, no. 6 (December 2013): 630–34. http://dx.doi.org/10.1590/0103-6440201302241.

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This study evaluated the tensile and flexural strength of tungsten inert gas (TIG) welds in specimens made of commercially pure titanium (CP Ti) compared with laser welds. Sixty cylindrical specimens (2 mm diameter x 55 mm thick) were randomly assigned to 3 groups for each test (n=10): no welding (control), TIG welding (10 V, 36 A, 8 s) and Nd:YAG laser welding (380 V, 8 ms). The specimens were radiographed and subjected to tensile and flexural strength tests at a crosshead speed of 1.0 mm/min using a load cell of 500 kgf applied on the welded interface or at the middle point of the non-welded specimens. Tensile strength data were analyzed by ANOVA and Tukey's test, and flexural strength data by the Kruskal-Wallis test (α=0.05). Non-welded specimens presented significantly higher tensile strength (control=605.84±19.83) (p=0.015) and flexural strength (control=1908.75) (p=0.000) than TIG- and laser-welded ones. There were no significant differences (p>0.05) between the welding types for neither the tensile strength test (TIG=514.90±37.76; laser=515.85±62.07) nor the flexural strength test (TIG=1559.66; laser=1621.64). As far as tensile and flexural strengths are concerned, TIG was similar to laser and could be suitable to replace laser welding in implant-supported rehabilitations.

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Tseng, Kuang Hung, Yung Chang Chen, and Kuan Lung Chen. "Cr₂O₃ Flux Assisted TIG Welding of Type 316L Stainless Steel Plates." Applied Mechanics and Materials 121-126 (October 2011): 2592–96. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.2592.

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An exploratory study was conducted to investigate the effect of Cr2O3 flux used in tungsten inert gas (TIG) welding on the weld morphology, retained ferrite content, welding residual stress, and hot cracking susceptibility when welding 5 mm thick type 316L stainless steel plates. The results showed that Cr2O3 flux assisted TIG welding can create a high depth-to-width ratio weld. Since the activated TIG welding can reduce the heat input per unit length in welds, and the residual stress of the weldment can be reduced. TIG welding with Cr2O3 flux can increase the retained ferrite content of stainless steel 316L weld metal and, in consequence, the hot cracking susceptibility is reduced.

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Madicke, H.-H., M. Kiesche, and E. Tilgner. "The welding of steel X2 CrNiMoN 18.12 part 2: TIG welding." Welding International 2, no. 6 (January 1988): 554–57. http://dx.doi.org/10.1080/09507118809447520.

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Bozhena, Jhas, Shrivani Sriskanthadevan, Marko Skrtic, Mahadeo A. Sukhai, Veronique Voisin, Yulia Jitkova, Marcela Gronda, et al. "Chronic Inhibition of Mitochondrial Translation Alters Metabolism and Stemness in AML." Blood 120, no. 21 (November 16, 2012): 1364. http://dx.doi.org/10.1182/blood.v120.21.1364.1364.

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Abstract Abstract 1364 Recently, we demonstrated that the anti-bacterial agent tigecycline preferentially induces death in AML and AML stem cells over normal hematopoietic cells through the inhibition of mitochondrial translation. This heightened sensitivity was due to increased mitochondrial mass and reliance on oxidative metabolism in the AML cells compared to normal hematopoietic cells. Here, we sought to better understand the mechanisms of sensitivity and resistance to inhibitors of mitochondrial translation. To establish cells resistant to tigecycline, we exposed TEX leukemia cells to increasing concentrations of tigecycline over 4 months and selected a population of TEX cells resistant to tigecycline (RTEX+TIG) with an IC50 > 24 μM (versus an IC50 of 2.8 + 0.4 μM in wild type cells). We then profiled oxidative metabolism in the resistant cells. In RTEX+TIG cells, levels of Cox-1 and Cox-2, subunits of respiratory complex IV in the electron transport chain that are translated by mitochondrial ribosomes, were undetectable. In contrast, Cox-4 that is part of the same respiratory chain, but translated in the cytoplasm, was only slightly reduced. RTEX+TIG cells also had undetectable levels of oxygen consumption and increased rates of glycolysis compared to wild type cells. Moreover, RTEX+TIG cells were more sensitive to inhibitors of glycolysis and more resistant to hypoxia, thus demonstrating the functional importance to the change in their metabolic status. RTEX+TIG cells also had reduced mitochondrial membrane potential by 44.4 + 7.2% and reduced mitochondrial mass compared to wild type cells. Morphologically, RTEX+TIG cells had abnormally swollen mitochondria with irregular cristae structures. To understand the molecular basis for the metabolic changes in the RTEX+TIG cells, we performed RNA sequencing of the RTEX+TIG cells and wild type TEX cells. Unbiased analysis, by two independent approaches, of the promoter sequences of transcripts upregulated 1.5-fold or greater in RTEX+TIG cells demonstrated a significant over-representation of binding sites for the hypoxia-inducible factor 1 alpha HIF1α :HIF1β transcription factor complex. Specifically, a subset of HIF1α target genes involved in energy balance and cellular metabolism were coordinately upregulated in RTEX+TIG cells, corresponding with our phenotypic observations of the metabolic state of these cells. We validated the upregulation of HIF1α mRNA and protein by Q-RTPCR and immunoblotting. Strikingly, upon removal of tigecycline from RTEX+TIG cells, the cells re-established aerobic metabolism and oxidative phosphorylation. Levels of Cox-1 and Cox-2, oxygen consumption, glycolysis, mitochondrial mass and mitochondrial membrane potential returned to wild type levels. However, HIF1α remained elevated. Upon re-treatment with tigecycline, the cells remained resistant and the glycolytic phenotype was re-established. TEX cells display features of leukemia stem cells, including differentiation, self-renewal and hierarchical organization. Interestingly, RTEX+TIG cells were more differentiated and had reduced stemness compared to the wild type TEX cells. By immunohistochemistry, RTEX+TIG had increased non-specific esterase activity (NSE). In addition, RTEX+TIG cells had reduced clonogenic growth and ability to engraft immune deficient mice compared to wild type cells. Moreover, RNA sequencing data showed reduced expression of stem cell maintenance genes in RTEX+TIG cells. Depletion of mitochondrial DNA via prolonged exposure of parental cell lines to cationic lipophilic agents such as ethidium bromide produces rho-zero cells that have irreversibly lost mitochondrially translated proteins. These cells lack a functional respiratory chain and cannot derive energy from oxidative phosphorylation. Instead, these cells rely on glycolysis for their energy supply. Here, we have produced a reversible rho-zero like metabolic phenotype by sustained inhibition of mitochondrial translation. This work, therefore, highlights mechanisms of metabolic adaption to inhibition of oxidative phosphorylation. Finally, these data suggest a unique role for metabolism in differentiation and stemness in AML. Disclosures: No relevant conflicts of interest to declare.

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Hinata, Teruhiko, Katsuhiko Yasuda, Yukio Kasuga, and Tadao Onzawa. "Study on Low Speed DC-TIG Welding Method(Report 2). Penetration Form and Welding of Practical Joint Using Traveling TIG Arc." QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY 12, no. 1 (1994): 58–63. http://dx.doi.org/10.2207/qjjws.12.58.

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Harjanto, Budi. "KAJI BANDING KUALITAS REPAIR WELDING DENGAN METODE OXY-ACITELYN, TIG DAN MIG PADA CAST WHEEL ALUMINIUM." Jurnal Ilmiah Pendidikan Teknik dan Kejuruan 12, no. 1 (January 30, 2019): 38. http://dx.doi.org/10.20961/jiptek.v12i1.28254.

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Penelitian yang telah dilakukan adalah reparasi cast wheel (velg) aluminium yang telah mengalami kerusakan (retak) dengan metode pengelasan. Pengalasan yang akan diteliti meliputi 3 metode yaitu: las Oksi-Asitelin, las TIG (Tungsten Inert Gas) dan MIG (Metal Inert Gas). Pengelasan pada velg berbahan Aluminium memungkinkan digunakan untuk memperbaiki kerusakan sejauh kekuatan sambungan las tersebut mendekati kekuatan dari velg utuh. Sebelum percobaan pengelasan Oksi-Asitelin, TIG dan MIG dilakukan, maka dilakukan dahulu beberapa pengujian untuk mengetahui data awal. Pengujian bertujuan untuk mengetahui kondisi material asli (base material). Dari pengujian awal diperoleh bahwa material asli adalah Al-7,3%Si yang memiliki kekerasan sebesar 57,63 HBN dan memiliki kekuatan impak sebesar 0,108 Joule/mm2. Data yang diperoleh pada pengujian tersebut merupakan data acuan untuk menjadi pembanding hasil percobaan dengan pengelasan Oksi-Asitelin, TIG dan MIG. Hasil uji kekerasan masing masing proses pengelasan pada daerah perbatasan antara logam induk dan logam lasan serta pada logam lasan, untuk pengelasan Oksi-Asitelin sebesar 38,69 BHN dan 54,80 BHN, untuk pengelasan TIG sebesar 30,47 BHN dan 45,15 BHN, sedangkan untuk pengelasan MIG sebesar 36,16 BHN dan 44,18 BHN. Hasil uji impak untuk masing-masing proses pengelasan, untuk pengelasan Oksi-Asitelin sebesar 0,085 Joule/mm2, untuk pengelasan TIG sebesar 0,096 Joule/mm2 dan untuk pengelasan MIG sebesar 0,102 Joule/mm2. Dari hasi pengujian kekerasan dan impak dapat diketahui bahwa nilai kekerasan dan kekuatan impak hasil lasan masih lebih kecil dibandingkan dengn kekerasan dan kekuatan impak logam induk. Hal ini berarti bahwa hasil pengelasan belum layak digunakan, karena nilai kekerasan dari hasil pengelasan belum mendekati nilai kekerasan logam induk.

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Liu, Meng Ru, Han Chi Cheng, Lan Li, Shang Li, and Chang Shun Huang. "Characterization of In Situ Synthesized TiC-TiB₂ Reinforced Fe Matrix Wear-Resistant Coating by TIG Arc/Cored-Wires Weld Overlaying Technology." Advanced Materials Research 1030-1032 (September 2014): 34–38. http://dx.doi.org/10.4028/www.scientific.net/amr.1030-1032.34.

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TiC-TiB2/ Fe matrix composite coatings were in-situ synthesized in the surface of Q235 steel substrate by TIG/cored-wire weld overlaying. The microstructure, micro-hardness and wear resistance of the weld overlay coating were investigated using SEM, XRD, Micro-hardness Tester and Pin-disc Wear Tester respectively. The results showed that the weld overlay coating presented a dense microstructure with defect-free of pore and crack, and better metallurgical bond with the substrate; TiC and TiB2 particulate distributed dispersively in Fe matrix of the weld overlay coatings. The highest Micro-hardness of the weld overlaying was 1657.58HV, which is 6 times higher than the substrate, and wear resistance are also improved at the room temperature under normal atmosphere conditions.

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Matos, Adaias Oliveira, Cristiane de Castro Castelo Branco, Eliza Burlamaqui Klautau, and Bruno Pereira Alves. "Comparative analysis of ceramic flexural strength in co-cr and ni-cr alloys joined by TIG welding and conventional brazing." Brazilian Journal of Oral Sciences 16 (December 15, 2017): 1–9. http://dx.doi.org/10.20396/bjos.v16i0.8650496.

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The purpose of the present study was to evaluate the flexural strength of specimens made of nickel-chromium (Ni-Cr) and cobalt-chromium (Co-Cr) alloys and joined by tungsten inert gas (TIG) welding and conventional brazing. Ni–Cr and Co–Cr base metal specimens (n = 40, each) were cast and welded by TIG or brazing. The specimens were divided into six groups (2 base metals, four welded specimens). Ceramic systems were applied to the central part of all the specimens. A three-point bending test with a velocity of 0.5 mm/m was performed on the specimens up to the point of the first ceramic bond failure by measuring the flexural strength. Data were analyzed using two-way ANOVA and Bonferroni’s tests. Conventional welding showed the lowest flexural strength results for both alloys, while the TIG weld and the control group presented with varying bond strengths for the alloys studied. We concluded that TIG welding was superior to the conventional welding method for both Ni–Cr and Co–Cr alloys with regard to the flexural strength of the ceramic.

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Li, Dong Jie, Shan Ping Lu, Dian Zhong Li, and Yi Yi Li. "Weld Pool Shape Variations and Electrode Protection in Double Shielded TIG Welding." Advanced Materials Research 97-101 (March 2010): 3978–81. http://dx.doi.org/10.4028/www.scientific.net/amr.97-101.3978.

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A new welding method named double shielded TIG welding has been investigated and is described in this paper. It is applicable to the TIG process and can improve the weld depth/width ratio and protect the electrode from oxidation during the welding process. A two pipeline structure is designed in the torch. Pure inert gas passes though the inner pipeline which keeps the arc stable and protects the tungsten electrode. A mixed gas containing an active gas passes through the outer pipeline. The active element which is decomposed from the active gas dissolves in the weld pool so as to change the Marangoni convection from an outward to an inward direction, and, as a result, the weld pool shape becomes deep and narrow. The double shielded TIG welding method increases the weld depth by about 2~3 times over the conventional TIG welding. The effects of the active gas (oxygen) in the outer pipeline on the weld pool shapes are discussed. Heavy oxide layer is considered to weaken the Marangoni convection and changes the weld pool shape.

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Carek, Andreja, Jasenka Zivko Babic, Zdravko Schauperl, and Tomislav Badel. "Mechanical Properties of Co-Cr Alloys for Metal Base Framework." International Journal of Prosthodontics and Restorative Dentistry 1, no. 1 (2011): 13–19. http://dx.doi.org/10.5005/jp-journals-10019-1003.

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ABSTRACT Purpose This study investigated the effect of two welding methods on the mechanical properties of a cobalt-chromium (Co-Cr) alloy for metal base framework. Materials and methods Fifty-four plates were cast for TIG and laser welding. Cobalt-chromium for plates were prepared and divided into three groups of 18 samples. Group 1 and 2 were cut at the center of the plate. Eighteen specimens were joint by using TIG (Primotec Phaser Mx1), and other 18 by laser (Nd:YAG laser). Specimens in the as-cast condition were used as control group (group 3). After joining, each specimen was microscopic analyzed and tested to flexural and dynamic failure. Failure loads were recorded and fracture strength calculated. Results The changes in microstructure and micro-hardness were studied in the heat-affected zones (HAZ) and unaffected zones. Micro- hardness values increased in the heat-affected zone (HAZ) and in welded material compared to the parent material. The ANOVA test showed a highly significant difference (α = 0.05) between the joint strengths of the as-cast control specimens and, TIG and laser-welded joints. The flexural and dynamic strength of the joints were higher than those for the TIG-welded joints, and both were higher than the laser-welded joint strengths for the tested Co-Cr alloy. Conclusions Although laser is more popular, in our research TIG showed better results for flexural and dynamic strength.

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Tseng, Kuang Hung, and Kai Chieh Hsien. "Effect of Ar-N₂ Mixed Gas on Morphology and Microstructure of Type 316L Stainless Steel TIG Weld Metal." Advanced Materials Research 295-297 (July 2011): 1919–24. http://dx.doi.org/10.4028/www.scientific.net/amr.295-297.1919.

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The aim of the present work was to investigate the effects of specific nitrogen gas additions to argon shielding gas on morphology and microstructure of austenitic stainless steel TIG welds. An autogenous TIG welding process was applied on type 316L stainless steel to produce a bead-on-plate weld. The ferrite content of weld metal was measured using a Feritscope. The results indicated that the arc voltage increase as the amount of nitrogen gas added to the argon atmosphere increases. The retained ferrite content of type 316L stainless steel TIG weld metal decreased rapidly as nitrogen gas addition to the argon shielding gas was increased.

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Yasuda, K., Y. Ishizawa, and I. Kitaura. "Study of a hybrid joining method using TIG welding: Aluminium alloy (Report 2)." Welding International 12, no. 1 (January 1998): 13–19. http://dx.doi.org/10.1080/09507119809448960.

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Nugraha, Sandi, and Herry Oktadinata. "Pengaruh Metode Pengelasan TIG dan SMAW Terhadap Sifat Mekanik Baja Karbon SS400." JURNAL ILMIAH TEKNIK MESIN 10, no. 1 (February 2, 2022): 37–44. http://dx.doi.org/10.33558/jitm.v10i1.2947.

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Welding methods that greatly affect welding, heat input in a process that can affect the cooling rate, an increase in the amount of heat input used, the cooling rate will be slower, and vice versa increasing the heat input used, the cooling rate will be faster, the cooling rate is faster. will quickly increase the hardness value of the welding results. This research was conducted on 6 pieces of SS400 carbon steel plate with dimensions of 250x100x10mm. The welding method used is the TIG and SMAW method, with a welding position of 1G and the type of connection is single v butt joint, the electrode used is E6010 with a diameter of 2.6 mm. There are 3 welding samples, where sample 1 was welded by the TIG method, sample 2 by the SMAW method. and sample 3 using the combined TIG&SMAW method. Rockwell hardness testing uses the ASTM E-18 standard with area testing on weld metal, HAZ and Base metal. Tensile testing using the AWS D1.1 standard and the microstructure standard used ASTM E3. The highest average tensile strength value is found in the combined combined sample (sample 3) of 467.5 MPa. From the test results, it was found that the sample that had the highest hardness value was a combined sample of TIG and SMAW in the weld metal area of 34.5 HRC. The distribution of the perlitee phase in sample 1 was 15.39%. In sample 2 as much as 15.80%, and in sample 3 as much as 15.52%. The teaching method greatly affects the mechanical properties of the welding results.

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Oliva, Alessandra, Stefania Garzoli, Massimiliano De Angelis, Carolina Marzuillo, Vincenzo Vullo, Claudio Mastroianni, and Rino Ragno. "In-Vitro Evaluation of Different Antimicrobial Combinations with and without Colistin Against Carbapenem-Resistant Acinetobacter Baumannii." Molecules 24, no. 5 (March 3, 2019): 886. http://dx.doi.org/10.3390/molecules24050886.

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Carbapenem-resistant Acinetobacter baumannii (CR-Ab) infections are associated with high morbidity and mortality. The aim of the study was to evaluate the in-vitro activity of different antimicrobial combinations (with and without colistin, COL) against clinical isolates of CR-Ab collected from patients with CR-Ab infection, including unconventional combinations such as COL + VANcomycin (VAN) and COL + rifampin (RIF). CR-Ab strains were collected from hospitalized patients at Sapienza University of Rome. Antimicrobial susceptibility patterns were determined throughout MIC50/90s whereas the synergistic activity was evaluated by qualitative (i.e., checkerboard) and quantitative (i.e., killing studies) methods. All the strains were found oxacillinase (OXA) producers and tigecycline (TIG) sensitive whereas 2 strains were resistant to COL. Application of the checkerboard method indicated complete synergism in COL combinations at different extension: 21.4%, 57.1%, 42.8%, 35.7% for COL + meropenem (MEM), COL + RIF, COL + VAN and COL + TIG, respectively, with the non-conventional combinations COL + VAN and COL + RIF exhibiting the highest rate of synergism. Regarding COL-free combination, complete synergism was observed in 35.7% of the strains for MEM + TIG. Killing studies showed that the combinations COL + MEM, COL + TIG and MEM + TIG were bactericidal and synergistic against both colistin-sensitive and low colistin-resistant strains whereas only the combinations COL + VAN and COL + RIF showed an early and durable bactericidal activity against all the tested strains, with absence of growth at 24 h. This study demonstrated that COL-based combinations lead to a high level of synergic and bactericidal activity, especially COL + VAN and COL + RIF, even in the presence of high level of COL resistance.

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Marin, Robert Cristian, Iulian Ştefan, Răzvan Ionuţ Iacobici, and Sorin Vasile Savu. "Preliminary Research for Development of MW-TIG Hybrid Welding System." Advanced Materials Research 1164 (June 23, 2021): 9–15. http://dx.doi.org/10.4028/www.scientific.net/amr.1164.9.

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The paper aims to report preliminary researches towards to development of new hybrid welding system by coupling a microwave beam with a TIG torch. The main research was focused on the designing of hybrid system as well as to establish the heating/welding mechanism by coupling two different thermal sources. Therefore, a specific welding chamber was designed taking into consideration the limitations provided by microwave waveguide technical specs, geometrical shape and dimensions of the TIG torch as well as the temperature monitoring during welding process and video surveillance for data recording. A microwave generator with adjustable power from 0 to 1250 W was coupled with a TIG torch and welding power source in order to establish the main parameters for hybrid system. The preliminary researches reported that the MW-TIG hybrid welding could be applied to eutectic joining of materials using low power (up to 600 W) injected from microwave generator as well as low welding current (up to 20 A). The flow of shielding gas have been established initially to 2 l/m. The research related to stabilization of MW-WIG plasma arc have been studied by increasing the flow of shielding gas up to 10 l/m. The results have shown that the microwave generator and TIG torch can be coupled to obtain hybrid-welding process without any matching tuning devices but with risks for damaging the microwave generator. Further researches will be done in order to design auxiliary devices to optimize the hybrid-welding process and to avoid any unwanted plasma arc discharge from welded base materials to microwave generator. In terms of temperature monitoring, an infrared pyrometer has been used. The IR pyrometer was targeted to the base materials in order to be able to measure their temperature without any influences from plasma arc. The results obtained have shown a stable plasma at average microwave power around 400 W even without any TIG current.

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ZHAO, LEI, YINGCHUN GUAN, QIANG WANG, BAOQIANG CONG, and BOJIN QI. "ANALYSIS AND COMPARISON OF ALUMINUM ALLOY WELDED JOINTS BETWEEN METAL INERT GAS WELDING AND TUNGSTEN INERT GAS WELDING." Surface Review and Letters 22, no. 06 (October 20, 2015): 1550079. http://dx.doi.org/10.1142/s0218625x15500791.

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Surface contamination usually occurs during welding processing and it affects the welds quality largely. However, the formation of such contaminants has seldom been studied. Effort was made to study the contaminants caused by metal inert gas (MIG) welding and tungsten inert gas (TIG) welding processes of aluminum alloy, respectively. SEM, FTIR and XPS analysis was carried out to investigate the microstructure as well as surface chemistry. These contaminants were found to be mainly consisting of Al 2 O 3, MgO , carbide and chromium complexes. The difference of contaminants between MIG and TIG welds was further examined. In addition, method to minimize these contaminants was proposed.

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Yang, Qing Feng, Cun Juan Xia, and Ya Qi Deng. "Microstructure and Mechanical Properties of TiB₂/ Al-Si Composites Fabricated by TIG Wire and Arc Additive Manufacturing." Materials Science Forum 944 (January 2019): 64–72. http://dx.doi.org/10.4028/www.scientific.net/msf.944.64.

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Bulky sample was made by using TIG wire and arc additive manufacturing (WAAM) technology, in which Ф1.6 mm filler wire of in-situ TiB2/Al-Si composites was selected as deposition metal, following by T6 heat treatment. The microstructure and mechanical properties of the bulky sample before and after heat treatment were analyzed. Experimental results showed that the texture of the original samples parallel to the weld direction and perpendicular to the weld direction was similar consisting of columnar dendrites and equiaxed crystals. After T6 heat treatment, the hardness of the sample was increased to 115.85 HV from 62.83 HV, the yield strength of the sample was 273.33 MPa, the average tensile strength was 347.33 MPa, and the average elongation after fracture was 7.96%. Although pore defects existed in the fracture, yet the fracture of the sample was ductile fracture.

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Sawabe, Akiyoshi, Ayato Tanaka, Masato Nomura, and Ryuji Takeda. "Skin-Beautifying Effects of Magnolol and Honokiol Glycosides." Processes 10, no. 7 (June 22, 2022): 1241. http://dx.doi.org/10.3390/pr10071241.

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Glycosides have been synthesized using the starting materials magnolol (1) and honokiol (4), isolated from the Japanese white-bark magnolia, and their anti-aging effects on the skin (skin-beautifying effects) have been examined. The advanced glycation end-product (AGE) inhibitory activity test (anti-glycation test) and glycation induction model test, using human-derived dermal fibroblasts, TIG-110 cells, have been conducted to evaluate the anti-aging effects. The synthesized glycoside compounds, 5,5′-di(prop-2-en-1-yl)[1,1′-biphenyl]-2-hydroxy-2′-glucopyranoside (3a), 5,5′-di(prop-2-en-1-yl)[1,1′-biphenyl]-2,2′-diglucopyranoside (3b), 3′,5-di(prop-2-en-1-yl)[1,1′-biphenyl]-4′-hydroxy-2-glucopyranoside (6a) and 3′,5-di(prop-2-en-1-yl)[1,1′-biphenyl]-2,4′-diglucopyranoside (6b), have shown significant anti-glycation activities of less than 0.10 mM in IC50. The glycation induction model test with the fibroblasts, TIG-110 cells, demonstrates that the aforementioned glycosides significantly inhibit the decrease in cell viability. These newly synthesized glycoside compounds are expected to be used as cosmetic ingredients, health foods, and pharmaceutical ingredients, which have inhibitory effects against AGE formation.

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Ghaffarpour, Morteza, Mohammad Kazemi, Mohammad Javad Mohammadi Sefat, Ahmad Aziz, and Kamran Dehghani. "Evaluation of dissimilar joints properties of 5083-H12 and 6061-T6 aluminum alloys produced by tungsten inert gas and friction stir welding." Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications 231, no. 3 (July 14, 2015): 297–308. http://dx.doi.org/10.1177/1464420715595652.

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In the present study, friction stir welding (FSW) and tungsten inert gas (TIG) techniques were used to join the dissimilar aluminum alloys of 5083-H12 and 6061-T6. The laboratory tests were designed using design of experiment (DOE) method. Variables for the FSW process were the rotational speed, traverse speed, shoulder diameter, and pin diameter. They changed in ranges of 700–2500 r/min, 25–400 mm/min, 10–14 mm, and 2–4 mm, respectively. In the case of TIG process, the variables were current intensity, traverse speed, and tilt angle. These parameters varied from 80 to 90 A, 200 to 400 mm/min, and 3° to 12°, respectively. The optimum amounts of parameters were obtained using response surface methodology (RSM). The RSM-based model was developed to predict ultimate tensile strength (UTS) of the welds produced. In FSW, the difference between predicted and measured UTS was about 1.28% and in TIG it was 1.78%. The good agreement between experimental and predicted results indicates the high accuracy of the developed model. Mechanical properties and also the microstructure of the welds were compared after optimizing both welding processes using RSM. The results showed that the welds produced by FSW indicated a considerably higher quality and also improved mechanical properties compared to TIG. Properties of the joints obtained by FSW in single-sided joints were more desirable. In the double-sided welds obtained by FSW these differences were of an even higher significance.

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Xu, Pei Quan, Jiang Wei Ren, and Hong Ying Gong. "Microstructure Characterization of AZ91D Magnesium Alloy Weldment Using Tungsten Inert Arc Welding Method." Advanced Materials Research 322 (August 2011): 31–34. http://dx.doi.org/10.4028/www.scientific.net/amr.322.31.

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The problem during magnesium alloy welding is the key bottleneck of magnesium application in aerospace, aircraft, automotive and other industries. AZ91D magnesium welded joint is obtained using tungsten inert gas (TIG) welding method without filler materials and groove. The microstructure, morphology, composition and micro hardness distribution of welded joint are investigated using scanning electronic microscopy (SEM), EDAX and micro hardness experiment. The results show: (1) Well welded joint of AZ91D magnesium alloy using TIG welding method is obtained under the condition of welding current 152A, welding voltage 13.4V, welding velocity 6.5mm/s and 20L/min Argon shielding gas; (2) Microstructure of welded joint consisted of black matrix phase α-Mg, white eutectic α+Mg17Al12 and gray dendrite.

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Vana, Daniel, Pierre-Emmanuel Gaillardon, and Adam Teman. "C$^\text{2}$TIG: Dynamic C$^\text{2}$MOS Design Based on Three-Independent-Gate Field-Effect Transistors." IEEE Transactions on Nanotechnology 19 (2020): 123–36. http://dx.doi.org/10.1109/tnano.2020.2965119.

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van Es, S. H. J., M. H. Kolstein, R. J. M. Pijpers, and F. S. K. Bijlaard. "TIG-dressing of High Strength Butt Welded Connections – Part 2: Physical Testing and Modelling." Procedia Engineering 66 (2013): 126–37. http://dx.doi.org/10.1016/j.proeng.2013.12.068.

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Górka, J., M. Przybyła, M. Szmul, A. Chudzio, and D. Ładak. "Orbital TIG Welding of Titanium Tubes with Perforated Bottom Made of Titanium-Clad Steel." Advances in Materials Science 19, no. 3 (September 1, 2019): 55–64. http://dx.doi.org/10.2478/adms-2019-0017.

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AbstractThe article presents problems accompanying the industrial TIG welding (142) of a heat exchanger perforated bottom made of steel clad with titanium B265 grade 1 with tubes made of titanium B338 grade 2. Research-related tests involved the making of test plates containing simulated imperfections formed during orbital welding. The above-named imperfections resulted from insufficient gas shielding during the welding process, the improper positioning of the tungsten electrode (excessively large or overly small circumference, around which the orbital welding process was performed), an excessive electrode travel rate being the consequence of an improperly set welding programme as well as excessively high welding current. Initial tests enabled the development of the orbital TIG welding of titanium tubes with the perforated bottom made of titanium-clad steel, satisfying acceptance criteria applied during commissioning.

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Tathgir, Surinder, Dinesh W. Rathod, and Ajay Batish. "Emphasis of Weld Time, Shielding Gas and Oxygen Content in Activated Fluxes on the Weldment Microstructure." Mechanical Engineering for Society and Industry 1, no. 2 (October 29, 2021): 86–95. http://dx.doi.org/10.31603/mesi.5903.

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The activated-TIG (A-TIG) process is a recognised process for achieving higher depth-of- penetration (DoP) and it could be used for various stainless-steel grades welding. The oxygen content of oxide based activated fluxes provide the extra heat during decomposition of flux and result into deep penetration. This study reveals the effect of short weld time of 2 sec in stationary arc, shielding environment (Ar and Ar + 2.5 % H2) and an effect of oxygen element in activated flux (CrO3 and SiO2) on the microstructure and weld metal micro-hardness. Use of hydrogen mix shielding gas during A-TIG process has significant impact on the dilution rate, grain size and dendrite arm spacing. The fraction of oxygen in the flux and the presence of silicon in SiO2 flux play a significant role in achieving higher DoP. To evaluate the impact of different shielding environment on grain growth, the samples were investigated with weld pool morphology, depth of penetration, weld chemistry, optical microscopy and SEM analysis. The extra heat produced due to oxygen fraction in activated flux and H2 induced shielding have been quantified in the study. The ferrite and austenite grain growth as well as the dendrite arm spacing found to be increased due to presence of H2 in shielding gas.

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SAIDOV, RUSTAM MANNAPOVICH, DURDONA RUSTAMOVNA KOMILOVA, MARIO KUSCH, PETER MAYR, and KEVIN HOEFER. "STUDY ON ENERGY EFFICIENCY OF A-TIG WELDING OF STAINLESS STEELS USING INDIVIDUAL FLUX-OXIDES. PART 2. INFLUENCE OF THERMODYNAMIC AND PHYSICO-CHEMICAL PROPERTIES OF FLUX-OXIDES." Computational nanotechnology 6, no. 3 (September 30, 2019): 32–38. http://dx.doi.org/10.33693/2313-223x-2019-6-3-32-38.

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This paper presents the results of studies on the influence of thermodynamic and physico-chemical properties of individual flux-oxides on the energy efficiency of the arc A-TIG welding of stainless steel CrNi18-10. The obtained results of the research allowed to reveal the criteria for evaluating the energy efficiency of the arc A-TIG welding on the depth of penetration of the welded metal and to determine the impact of thermodynamic and physico-chemical properties of individual flux oxides on the energy efficiency of the penetration capability of the welding arc for different welding energies. The requirements to thermodynamic and physico-chemical properties of individual fluxes-oxides are also revealed, which provide high energy efficiency of arc penetration capability during A-TIG welding.

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Tanaka, Manabu, Kentaro Yamamoto, Tashiro Shinichi, and John J. Lowke. "Predictions of Current Attachment at Thermionic Cathode for TIG Arcs." Materials Science Forum 580-582 (June 2008): 319–22. http://dx.doi.org/10.4028/www.scientific.net/msf.580-582.319.

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Study of current attachment at thermionic cathode for TIG arc at atmospheric pressure is attempted from numerical calculations of arc-electrodes unified model. The calculations show that the maximum temperature of arc plasma close to the cathode tip for W-2% ThO2 reaches 19,000 K and it is the highest value in comparison with the other temperatures for W-2% La2O3 and W-2% CeO2, because the current attachment at the cathode tip is constricted by a centralized limitation of liquid area of ThO2 due to its higher melting point. The calculations also show that, in cases of W- 2% La2O3 and W-2% CeO2, the liquid areas of La2O3 and Ce2O3 are widely expanded at the cathode tip due to their lower melting points and then produce uniform current attachments at the cathode. It is concluded that the current attachment at thermionic cathode is strongly dependent on work function, melting point and Richardson constant of emitter materials.

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Kikani, Pratik T., Hemantkumar R. Thakkar, and Sagarkumar I. Shah. "Weld Strength and Cracking Susceptibility Analysis of Pulsed TIG Welded Al-Mg-Si Alloy by Experimental Approach." Jurnal Kejuruteraan 34, no. 5 (September 30, 2022): 825–30. http://dx.doi.org/10.17576/jkukm-2022-34(5)-08.

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Aluminium is a non ferrous corrosive resistance metal mainly used in automotive coolers, inter coolers and radiators. They are the part of automobile vehicles and made from aluminium alloys. The joints in this application are created by fusion welding process specifically Tungsten Inert Gas (TIG) and Pulsed current TIG (PCTIG) welding process. The working temperature range of different coolers, radiators are 20° C to 300° C and pressure ranges from 2.5 bar to 3.5 bar. During actual working of coolers, the weld joint experiences sudden high level and low level temperature changes. These will create high thermal stresses in the joints. It leads to cracking in the weld region and create failure of the weld joints. Various factors such as mechanical, metallurgical and thermal are responsible for cracking in the weld joints. Range of solidification temperature is one of metallurgical factor, stress generation is mechanical factor and cooling rate of weld metal is thermal factor for cracking. Houldcroft weldability test is employed to identify the cracking susceptibility (CS) of the weld. The current investigation is intended to discover the effect of pulse TIG welding process parameters on the mechanical properties and cracking susceptibility of precipitated aluminium Al-Mg-Si alloy. Diverse pulsed TIG welding process parameters such as peak current (Ip), base current (Ib) and frequency (f) were investigated with the objective of identify the tensile strength, yield strength and cracking susceptibility. The corresponding findings of optimum parameters are 180 peak current (Ip), 60 A base current (Ib) and at 6 Hz frequency (f) with tensile strength of 185.55 MP, yield strength 156.62 MPa. The significant of each parameter for tensile strength are Ip, Ib, Ip*Ib, Ip*f and Ib*f. The corresponding contributions in % are 14.56, 49.49, 12.26, 5.44, 12.15, 5.04, and 1.05 respectively. The statistical method such as Taguchi was employed for experiment design. Weldability test (Fishbone test) was performed on standard specimen and the cracking susceptibility index was identified. The cracking susceptibility index 5.26 % were observed with the value of 180 A of Ip, 80 A of Ib & 2 Hz of frequency (f).The results give an idea about the effect of pulsed TIG welding parameters on mechanical properties and cracking susceptibility.

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Olivares, Erick Alejandro González, and Victor Manuel Vergara Díaz. "Estudo do Processo TIG Hot-Wire com Material de Adição AISI-316L Analisando o Efeito do Sopro Magnético do Arco sobre a Diluição do Cordão de Solda." Soldagem & Inspeção 21, no. 3 (September 2016): 330–41. http://dx.doi.org/10.1590/0104-9224/si2103.08.

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Resumo: O processo TIG com adição de arame quente (HotWire) é considerado um processo altamente produtivo em comparação ao processo TIG convencional com arame frio (ColdWire), sendo possível alcançar grandes taxas de deposição e baixas porcentagens de diluição, características essas que permitem ao processo ser uma ótima alternativa para aplicações de revestimentos. Existem variadas opções em configurações de circuitos elétricos para aquecer o arame de adição no processo TIG Hot-Wire, entre elas podemos destacar a utilização da corrente contínua pulsada e a corrente alternada. No presente trabalho foi utilizada a corrente contínua constante e foram estudadas duas configurações do circuito elétrico para aquecer o material de adição, as quais em teoria provocam diferentes comportamentos no arco voltaico e, portanto, nas propriedades geométricas do cordão de solda. Uma primeira análise realizada sobre o arco voltaico demonstra que se forma um sopro mágnetico constante ao se aquecer o arame com corrente contínua constante. Segundo os ensaios realizados, a direção do sopro magnético depende da polaridade da corrente para aquecer o arame. Uma análise macrográfica dos cordões de solda obtidos demonstraram que os melhores resultados foram para os ensaios feitos com Hot-Wire, conseguindo diluições de até um 2% aproximadamente para uma velocidade de arame de 7,5 m/min, 1 kW de potência de aquecimento do arame e usando uma velocidade de soldagem de 30 cm/min.

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Harishkumar, Madhyastha, Yamaguchi Masatoshi, Sameshima Hiroshi, Ikenoue Tsuyomu, and Maruyama Masugi. "Revealing the Mechanism ofIn VitroWound Healing Properties ofCitrus tamuranaExtract." BioMed Research International 2013 (2013): 1–8. http://dx.doi.org/10.1155/2013/963457.

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In the present investigation, we examined the effect of Hyuganatsu (Citrus tamurana) extract (HE) on skin fibroblast (TIG-119) proliferation and migration duringin vitrowound healing. HE selectively inhibited proliferation of TIG-119 cells at higher concentration (>1.0 mg/mL); at lower concentrations (0.1, 0.25, 0.5, and 0.75 mg/mL), it exhibited linear and time-dependent cell proliferation.In vitroscratch wound healing studies showed that the HE also accelerated the migration of cells towards the wounded region. Cytometric analysis demonstrated that HE extract did not alter G1/0 and S phases of cell cycle in any concentration studied; however, G2/M phases of cell cycle were significantly (P<0.05) accelerated at 0.75 mg/mL dose. RT-PCR and Western blotting analysis indicated that HE markedly overexpressed levels of Rac-1, Rho-A, and Cdc-42 mRNA and the respective proteins. Cyclin-dependent kinases (Cdk-1 and -2) gene expression activity was significantly (P<0.05) increased, but protein content decreased during treatment with HE. The induction of Cdk-1 and -2 by HE was abolished by inhibitors, transcription (DRB), and translation (CHX), implying transcriptional regulation that requiredde novoprotein synthesis.

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Patil, Hiralal, D. PATEL, and C. PATIL. "Characterizations of TIG welded joints of Unalloyed Commercially Pure Titanium Gr-2 for Weld Process Parameters." Frattura ed Integrità Strutturale 13, no. 48 (March 2, 2019): 377–84. http://dx.doi.org/10.3221/igf-esis.48.36.

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Huang, Vanthida, and Michael J. Rybak. "Pharmacodynamics of Cefepime Alone and in Combination with Various Antimicrobials against Methicillin-Resistant Staphylococcus aureus in an In Vitro Pharmacodynamic Infection Model." Antimicrobial Agents and Chemotherapy 49, no. 1 (January 2005): 302–8. http://dx.doi.org/10.1128/aac.49.1.302-308.2005.

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ABSTRACT Treatment options for gram-positive resistant bacteria are limited; therefore, efforts to evaluate therapy options in the critical care population are warranted. Cefepime has broad-spectrum activity against gram-negative and gram-positive organisms. We have previously demonstrated that the combination of cefepime with vancomycin, linezolid, or quinupristin-dalfopristin had an improved or enhanced effect against methicillin-resistant Staphylococcus aureus (MRSA). We investigated various regimens of cefepime alone and in combination against two clinical MRSA isolates (R2481 and R2484) in an established in vitro pharmacodynamic model. Human pharmacokinetic regimen simulations were as follows: cefepime, 2 g every 8 h (q8h) (C8) and 12 h (C12), continuous-infusion 2-g loading dose followed by 4 g alone or in combination with gentamicin and tobramycin (1.0 or 2.0 [G1 and G2 or TB1 and TB2] mg/kg of body weight q12h and 5.0 [G5 or TB5] mg/kg q24h), arbekacin (ARB) (100 mg q12h), linezolid (LIN) (600 mg q12h), tigecycline (TIG) (100 mg q24h), or daptomycin (DAP) (6 mg/kg q24h) for 48 h. The MICs for cefepime, gentamicin, tobramycin, ARB, LIN, TIG, and DAP for the two clinical MRSA isolates (R2481 and R2484) were 4 and 4, 0.25 and 0.5, 128 and 0.5, 0.5 and 0.125, 2 and 4, 0.25 and 0.25, and 0.0625 and 0.125 μg/ml, respectively. At 48 h, combinations of C12 and C8 plus ARB, G1, or G5 (range, −2.05- to −4.32-log10 decrease) demonstrated enhanced lethality against R2481 (resistant to tobramycin) (P < 0.05). A similar relationship was demonstrated against R2484 with cefepime plus ARB, gentamicin, or tobramycin (range, −2.05- to −3.63-log10 decrease) (P < 0.05). A 99.9% kill was achieved with cefepime plus aminoglycoside combinations as early as 2 h and maintained throughout the 48-h period. TIG was antagonistic when combined with C12 against both isolates. DAP alone achieved 99.9% kill for up to 48 h for both isolates and was the most active agent against R2481 and R2484 (−2.89- and −3.61-log10 decrease at 48 h); therefore, combination therapy did not enhance lethality. Overall, the most potent combinations noted were cefepime in combination with low- and high-dose aminoglycosides. Further investigations with combination therapies are warranted.

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Wang, Zheng Lun, Zhi Xiang Wang, and Yu Zhang. "Study on Welding Parameters Optimization of Duplex Stainless Steel 2205 Based on Orthogonal." Advanced Materials Research 472-475 (February 2012): 1305–8. http://dx.doi.org/10.4028/www.scientific.net/amr.472-475.1305.

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For the duplex stainless steel 2205 used to make into chemical ships in shipyards，TIG welding is used for the welding test of duplex stainless steel 2205. Residual stress on 2 mm thick welding specimen is tested with the slot-cuting method,and the distribution of longitudinal residual stress along weld cross-section has been found. Orthogonal test methods are also used in this paper to optimize welding parameters.

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NOMURA, Kazufumi, Kentaro SHIRAI, Takashi KISHI, and Yoshinori HIRATA. "Study on temperature measurement of two-electrode TIG arc plasma." QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY 31, no. 2 (2013): 133–40. http://dx.doi.org/10.2207/qjjws.31.133.

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El-Bitar, Taher, Maha El-Meligy, and Mohammed Gamil. "METALLURGICAL AND MECHANICAL INVESTIGATION OF TIG ARC WELDMENTS FOR API 32″ GAS PIPE." Acta Metallurgica Slovaca 28, no. 1 (March 15, 2022): 19–24. http://dx.doi.org/10.36547/ams.28.1.1324.

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API steel gas pipe of 32" diameter and 15.9 mm thickness was investigated to characterize the steel grade and assess weldability for fourteen-consecutive passes of TIG arc welding technology. The parent Metal (PM) contains 0.02% C in addition to 0.02% Nb. A steel electrode for TIG process was used containing 5.6% Cr and 0.56% Mo. Standard V-groove was mechanically prepared to suite butt welding. The microstructure of the PM was containing mainly fine acicular ferrite satisfying the essential requirements of API specifications for grade X60. The weld metal (WM) was containing very fine acicular ferrite and showing the maximum hardiness values. Heat affected zone (HAZ) structure still contains acicular ferrite but it became coarse, possessing lower hardness than that of WM. HAZ does not exceed 2-2.5 mm adjacent to the welded V-groove. The fractured tensile welded specimens were necked and failed at the HAZ. The impact transition temperature (ITT) was detected as -35 oC. However, the mechanical properties of the WM did not negatively affected by the welding process and still fair satisfying the requirements of API X60.

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Wartono, Wartono, and Aprianto Aprianto. "Pengaruh Arus Pengelasan Terhadap Sifat Mekanis Sambungan Butt-Joint Las TIG Aluminium." Jurnal Engine: Energi, Manufaktur, dan Material 5, no. 1 (May 12, 2021): 24. http://dx.doi.org/10.30588/jeemm.v5i1.848.

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Penelitian ini bertujuan untuk mengetahui pengaruh arus pengelasan terhadap sifat mekanis sambungan Tungsten Inert Gas (TIG) pada aluminium. Gas Tungsten Arc Welding (GTAW) atau Tungsten Inert Gas (TIG) adalah jenis las listrik yang menggunakan bahan tungsten sebagai elektroda tidak terkonsumsi. Elektroda ini digunakan untuk menghasilkan busur nyala listrik. Bahan penambah berupa batang las (rod), yang dicairkan oleh busur nyala tersebut, mengisi kampuh bahan induk. Untuk mencegah oksidasi digunakan gas mulia argon. Besar arus yang digunakan 130 A, 140 A, dan 150 A. Logam yang akan dilas adalah aluminium yang berukuran 300 mm x 100 mm x 4 mm, aluminium disambung dengan menggunakan logam pengisi filler ER5356. Hasil uji komposisi kimia raw material menunjukkan mempunyai unsur kandungan kemurnian Al 99,35%. Uji kekerasan vickers menunjukkan nilai kekerasan las tertinggi 130 A adalah sebesar 59,43 kg⁄mm2, kekerasan HAZ tertinggi 140 A adalah sebesar 66 kg⁄mm2 . Hasil pengujian tarik menunjukkan bahwa pengelasan dengan besar arus 140 A memiliki nilai tegangan tarik yang lebih tinggi yaitu 98,64 MPa.

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MANABE, Yukio, Hirokazu WADA, Satoru ZENITANI, Yoshinori HIROMOTO, and Yasuyuki HASHIMOTO. "Investigation on TIG Welding Using 2 Filler Wires with Electromagnetically Controlled Molten Pool Process in Horizontal Position." QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY 18, no. 1 (2000): 40–50. http://dx.doi.org/10.2207/qjjws.18.40.

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Wicaksono, Rochim Toat, Suharno Suharno, and Budi Harjanto. "PENGARUH KUAT ARUS PADA PENGELASAN PADUAN ALUMINIUM 6061 DENGAN MENGGUNAKAN METODE LAS TIG TERHADAP KEKERASAN DAN STRUKTUR MIKRO." NOZEL Jurnal Pendidikan Teknik Mesin 1, no. 1 (March 12, 2019): 37. http://dx.doi.org/10.20961/nozel.v1i1.28484.

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The objective of research was to find out the effect of current on microstructure and hardness value in Aluminium Alloy 6061 before (raw material) and after welding using Tungsten Inert Gas (TIG) welding method with filler rod ER4043. This research uses experiment methods. Technique of analyzing data used was a descriptive comparative research. The instruments used for testing microstructure and hardness were Olympus Metallurgical Microscope and Vikers Hardness Tester. Base on the result of research, it could be concluded that the result of microstructure testing showed the reduced Mg2Si phase width after welding. In raw material, the Mg2Si phase seemed to diffuse surrounding the α-Al phase surface, but the result of welding using TIG welding method with current of I00 A, 110 A, and 115A showed that Mg2Si phase reduced in each specimen, so that α-Al phase was very dominant. The hardness value of hardness result showed the different hardness level. The specimen with current of 110A had higher hardness level of 65.4 VHN than the specimen with current of 100 A (55.7 VHN) and 115 A (55.9 VHN). The result of hardness testing on raw material was 120.4 VHN. This research showed that the welding using varying current changed microstructure and affected the hardness value of Aluminum Alloy 6061.

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Krivtsun, I. V., I. V. Krikent, V. F. Demchenko, U. Reisgen, A. F. Zabirov, and O. A. Mokrov. "Interaction of CO₂-laser radiation beam with electric arc plasma in hybrid (Laser + TIG) welding." Paton Welding Journal 2015, no. 4 (April 28, 2015): 6–15. http://dx.doi.org/10.15407/tpwj2015.04.01.

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Poklaytsky, A. G., I. N. Klochkov, and S. I. Motrunich. "Structure and Properties of AMg2M Alloy Joints Made by Argon Nonconsumable – Arc Welding and Friction Stir Welding." Applied Mechanics and Materials 682 (October 2014): 166–69. http://dx.doi.org/10.4028/www.scientific.net/amm.682.166.

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Studied are the structural peculiarities of joints on AMg2M alloy of 2 mm thickness made by TIG and FSW. Their mechanical properties and fatigue resistance characteristics at alternating axial loads with asymmetry ratio of stress cycle Rσ = 0.1 were determined.It is determined that the welded joints failure along the base metal at tension and have ultimate strength at 170 MPa level. Restricted endurance limits of the joints, made FSW, exceed corresponding indices of the joints, made by NCAAW, for 10-15% in 105 – 2·106 fluctuation cycle endurance range and make 90-95% from the values of this index for the base metal.

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Matsuo, Yukiko, Risa Kurihara, Nana Akagi, and Yoshihiro Mimaki. "Two New Homoisoflavonoids from the Bulbs of Bessera elegans." Natural Product Communications 9, no. 12 (December 2014): 1934578X1400901. http://dx.doi.org/10.1177/1934578x1400901216.

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A further chemical investigation of the bulbs of Bessera elegans (Liliaceae) led to the isolation of a new homoisoflavonoid (1), a new scillascillin-type homoisoflavonoid (2), three known flavonoids (3–5), and two known norlignans (6 and 7). The structures of the new homoisoflavonoids (1 and 2) were determined based on the results of extensive spectroscopic analysis, including two-dimensional NMR data. The isolated compounds (1–7) were evaluated for cytotoxicity against HL-60 human promyelocytic leukemia cells and TIG-3 normal human diploid fibroblasts. Compound 1 exhibited potent tumor-selective cytotoxic activity against HL-60 cells.

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Pandolfi, Guilherme S., Felipe G. Pinheiro Rodrigues, and Paulo J. Modenesi. "Avaliação da Ocorrência de Constrição Mecânica do Arco na Soldagem A-TIG de Aços Inoxidáveis Austeníticos." Soldagem & Inspeção 21, no. 4 (January 5, 2017): 428–43. http://dx.doi.org/10.1590/0104-9224/si2104.04.

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Resumo Este trabalho avalia indícios de constrição do arco pelo isolamento elétrico e térmico por fluxos de óxidos de um componente na soldagem A-TIG de aços inoxidáveis austeníticos. Foram feitas filmagens do arco, medidas de sua tensão elétrica e da morfologia de cordões de solda obtidos com SiO2, Cr2O3 e Al2O3, aplicadas com duas densidades superficiais (30 e 60 g/m2) e aberturas centrais sem fluxo (1, 2 e 4 mm). Os resultados não mostraram mudança significativa na largura do arco nas condições utilizadas, não comprovando uma possível constrição mecânica no arco elétrico devido ao isolamento elétrico e térmico causado pelos fluxos. A filmagem lateral do arco indicou sua deflexão em sentido oposto ao de seu avanço para os três fluxos, sendo o efeito causado pela sílica o mais significativo. A abertura central sem fluxo reduziu a penetração, a área fundida do cordão e a largura do cordão. A ausência de indícios significativos de constrição do arco e a variação do formato do cordão de solda devido à abertura central sem fluxo favorecem o modelo da convecção de Marangoni como o mecanismo responsável pelo aumento de penetração na soldagem A-TIG de aços inoxidáveis austeníticos.

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Foolad, M. R., and G. Y. Lin. "Relationship between Cold Tolerance during Seed Germination and Vegetative Growth in Tomato: Germplasm Evaluation." Journal of the American Society for Horticultural Science 125, no. 6 (November 2000): 679–83. http://dx.doi.org/10.21273/jashs.125.6.679.

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Cold tolerance (CT) of 31 tomato accessions (cultivars, breeding lines, and plant introductions) representing six Lycopersicon L. sp. was evaluated during seed germination and vegetative growth. Seed germination was evaluated under temperature regimes of 11 ± 0.5 °C (cold stress) and 20 ± 0.5 °C (control) in petri plates containing 0.8% agar medium and maintained in darkness. Cold tolerance during seed germination was defined as the inverse of the ratio of germination time under cold stress to germination time under control conditions and referred to as germination tolerance index (TIG). Across accessions, TIG ranged from 0.15 to 0.48 indicating the presence of genotypic variation for CT during germination. Vegetative growth was evaluated in growth chambers with 12 h days/12 h nights of 12/5 °C (cold stress) and 25/18 °C (control) with a 12 h photoperiod of 350 mmol.m-2.s-1 (photosynthetic photon flux). Cold tolerance during vegetative growth was defined as the ratio of shoot dry weight (DW) under cold stress (DWS) to shoot DW under control (DWC) conditions and referred to as vegetative growth tolerance index (TIVG). Across accessions, TIVG ranged from 0.12 to 0.39 indicating the presence of genotypic variation for CT during vegetative growth. Cold tolerance during vegetative growth was independent of plant vigor, as judged by the absence of a significant correlation (r = 0.14, P > 0.05) between TIVG and DWC. Furthermore, CT during vegetative growth was independent of CT during seed germination, as judged by the absence of a significant rank correlation (rR = 0.14, P > 0.05) between TIVG and TIG. A few accessions, however, were identified with CT during both seed germination and vegetative growth. Results indicate that for CT breeding in tomato, each stage of plant development may have to be evaluated and selected for separately.

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Hadji, Y., A. Tricoteaux, M. G. Ben Ghorbal, M. Yahi, R. Badji, T. Sahraoui, M. Hadji, and M. W. Barsoum. "Microstructure and microindentation of Ti 3 SiC 2 – Titanium filler brazed joints by tungsten inert gas (TIG) process." Ceramics International 43, no. 9 (June 2017): 7290–94. http://dx.doi.org/10.1016/j.ceramint.2017.03.028.

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Journal articles on the topic 'TIG-2'

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