Academic literature on the topic 'Titanium, Effects of heat on; Titanium – Testing'
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Journal articles on the topic "Titanium, Effects of heat on; Titanium – Testing"
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Cremasco, Alessandra, Itamar Ferreira, and R. Caram. "Effect of Heat Treatments on Mechanical Properties and Fatigue Resistance of Ti-35Nb Alloy Used as Biomaterial." Materials Science Forum 636-637 (January 2010): 68–75. http://dx.doi.org/10.4028/www.scientific.net/msf.636-637.68.
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Titanium alloys form the most versatile class of metallic materials used as biomaterials. Among them it is foreseen that the type titanium alloy will be a prominent one for orthopedic applications. Aim of the present work was to prepare and characterize a type titanium alloy containing 35 wt.% Nb. Samples were cooled from the phase temperatures at different rates. This work includes the effects of heat treatment on the microstructure and hardness, tensile and fatigue properties in air at room temperature. The results showed that microstructure of slow cooled samples are formed by precipitates of and phases in a matrix. After rapid cooling, the microstructure consists of phase and ” martensite. Mechanical testing showed that the elastic modulus and Vickers hardness of slow cooled samples were significantly higher than that obtained by rapid cooling. On the other hand, it was observed that slow cooled samples showed higher tensile strength and lower ductility. The rapid cooled sample showed fatigue resistance higher than that of slow cooled samples.
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Chien, Philip Y.-H., Jorge N. R. Martins, Laurence J. Walsh, and Ove A. Peters. "Mechanical and Metallurgical Characterization of Nickel-Titanium Wire Types for Rotary Endodontic Instrument Manufacture." Materials 15, no. 23 (November 24, 2022): 8367. http://dx.doi.org/10.3390/ma15238367.
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This study aimed to evaluate and compare the effects of ambient temperature and post-manufacture heat-treatment on the mechanical behavior of nickel-titanium (NiTi) wires. Four types of commercial NiTi variants (Stock NiTi, heat treated “Blue”, “Gold”, “Superflex”, all Dentsply Maillefer, Ballaigues, Switzerland) were stressed in a tensile testing machine in a temperature-controlled water bath at three different temperatures. Stress and strain values were extrapolated from the raw data, and 2-way ANOVA and Tukey’s test for multiple comparisons were performed to compare the differences of the mechanical constants. Differential scanning calorimetry (DSC) tests established the martensitic transformation starting (Ms), finishing (Mf) and austenitic (reverse-martensitic) starting (As) and finishing (Af) points. Austenitic modulus of elasticity and transformation stress values increased with temperature for all NiTi groups. The martensitic modulus of elasticity, maximum transformation strain and ultimate tensile stress were not significantly affected by temperature changes. Stock NiTi and Gold wire samples presented with clearly delineated austenitic and martensitic transformations in the DSC experiments. Differences in manufacturing/heat treatment conditions and ambient temperature affect the mechanical behavior of nickel-titanium and may have clinical implications. Further improvements to the experimental setup could be considered to provide more accurate measurements of strain.
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Sarswat, Prashant, Taylor Smith, Sayan Sarkar, Arun Murali, and Michael Free. "Design and Fabrication of New High Entropy Alloys for Evaluating Titanium Replacements in Additive Manufacturing." Materials 13, no. 13 (July 6, 2020): 3001. http://dx.doi.org/10.3390/ma13133001.
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High entropy alloys (HEAs) were prepared using the powder bed fusion (PBF) technique. Among titanium free alloys AlCoCrFeNiMn, CoCr1.3FeMnNi0.7, AlCoCrFeNi1.3, and AlCoCr1.3FeNi1.3 have been further investigated. A cost comparison was done for these four alloys as well as the titanium-based alloys AlCoCrFeNiTi and AlCo0.8CrFeNiTi. Such a comparison was done in order to evaluate the performance of the titanium-free alloys as the estimated cost of these will be less than for Ti-based HEAs. Hence, we have chosen four titanium free alloys and two titanium-based alloys for further processing. All these alloys were fabricated and subsequently characterized for phase, purity and performance. Scanning electron microscopy-based images were captured for microstructure characterization. EIS-based tests and potentiodynamic scans were performed to evaluate corrosion current. Hardness tests were performed for mechanical properties evaluation. Additional testing using factorial design tests was performed to evaluate the effects of various parameters to create better PBF-based HEA samples. EBSD tests, accelerated corrosion tests (mass loss), chemical analysis after degradation, microstructure analysis before and after degradation, and mechanical property comparison for finalized samples and other similar tests were executed. The details about all these HEAs and subsequent laser processing as well as behavior of these HEAs have been included in this study. It has been observed that some of the selected alloys exhibit good performance compared to Ti-based alloys, especially with respect to improvements in elastic constant and hardness relative to commercially pure Ti.
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Vo, Phuong, Mohammad Jahazi, and Steve Yue. "Recrystallization during Beta Working of IMI834." Advanced Materials Research 15-17 (February 2006): 965–69. http://dx.doi.org/10.4028/www.scientific.net/amr.15-17.965.
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The microstructure evolution of near-alpha IMI834 titanium alloy during hot working in the beta phase temperature regime has been investigated with regard to the effects of deformation and heat treatments. Typical cogging conditions were simulated through compression testing at temperatures of 1025°C-1100°C, strain rates of 0.01s-1-1s-1, and post- deformation heat treatments up to 4h. An analysis of flow behaviour and as-deformed microstructures revealed mechanisms of dynamic recovery and recrystallization in operation during deformation. However, complete grain refinement was not achieved through dynamic recrystallization and subsequent heat treatment was required for microstructure homogenization through metadynamic recrystallization and grain growth. The mechanisms of dynamic and metadynamic recrystallization are considered through quantitative measures of beta grain size and available literature models.
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Sambale, Franziska, Frank Stahl, Ferdinand Rüdinger, Dror Seliktar, Cornelia Kasper, Detlef Bahnemann, and Thomas Scheper. "Iterative Cellular Screening System for Nanoparticle Safety Testing." Journal of Nanomaterials 2015 (2015): 1–16. http://dx.doi.org/10.1155/2015/691069.
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Nanoparticles have the potential to exhibit risks to human beings and to the environment; due to the wide applications of nanoproducts, extensive risk management must not be neglected. Therefore, we have constructed a cell-based, iterative screening system to examine a variety of nanoproducts concerning their toxicity during development. The sensitivity and application of various cell-based methods were discussed and proven by applying the screening to two different nanoparticles: zinc oxide and titanium dioxide nanoparticles. They were used as benchmarks to set up our methods and to examine their effects on mammalian cell lines. Different biological processes such as cell viability, gene expression of interleukin-8 and heat shock protein 70, as well as morphology changes were investigated. Within our screening system, both nanoparticle suspensions and coatings can be tested. Electric cell impedance measurements revealed to be a good method for online monitoring of cellular behavior. The implementation of three-dimensional cell culture is essential to better mimicin vivoconditions. In conclusion, our screening system is highly efficient, cost minimizing, and reduces the need for animal studies.
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Faizan, Ahmad, Jason Longaray, Jim E. Nevelos, and Geoffrey H. Westrich. "Effects of corrosion and cleaning method on taper dimensions: an in vitro investigation." HIP International 30, no. 1 (January 30, 2019): 87–92. http://dx.doi.org/10.1177/1120700018825448.
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Purpose: Taper corrosion related revisions have recently been reported in the orthopaedic literature. Cleaning procedure of the trunnions during hip revision is not standardised. The purpose of this bench top investigation was to understand the alterations in the trunnion dimensions and surface roughness characteristics as a result of corrosion product build-up. Methods: 8 titanium alloy trunnions and CoCr femoral heads assemblies were cyclically tested in a mechanical simulator. Following disassembly of the tested constructs, the trunnions were cleaned using 2 methods. The trunnion dimensions were measured using coordinate measuring machine, and surface roughness was measured using white light interferometry. The trunnions were reassembled with ceramic femoral heads and titanium sleeves following cleaning. Head/sleeve pull-off testing was conducted to understand the effects of cleaning methods on the pull-off strength. Results: Grade 4 corrosion was observed on all trunnions after mechanical testing. The aggressive cleaning methods had a larger impact on the surface roughness when compared to the light cleaning method. The aggressive cleaning method also decreased the taper cone angle. The pull-off strength was not affected by the cleaning method and the pull-off values were approximately 50% of the assembly loads. Conclusions: The study suggests that trunnion cleaning method may alter the surface roughness and taper cone angle of the existing trunnion. However, the effects of these changes on the pull-off strength did not reach statistical significance. Complex corrosion testing under cyclic loading conditions are warranted to understand the long-term effects of these changes.
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Mao, Jian Wei, Yuan Fei Han, Wei Jie Lu, and Li Qiang Wang. "Investigation of the Effect of Argon Arc Welding Parameters on Properties of Thin Plate of In Situ Titanium Matrix Composites." Materials Science Forum 849 (March 2016): 436–42. http://dx.doi.org/10.4028/www.scientific.net/msf.849.436.
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The weldability of in-situ titanium matrix composites (TMCs) was studied using the gas tungsten arc welding (GTAW). The effects of GTAW on the microstructure of fusion zone and heat-affected zone were discussed, and the changes of TiB whisker reinforcements in the welded joint were investigated by optical microscope (OM), scanning electron microscopy (SEM), XRD analysis and tension testing at room temperature. Research results show that the GTAW process is a suitable welding method for in-situ TMCs. Under reasonable welding parameters, the welded joints display goo weld seam formation, and TiB whiskers show distinctly smaller sizes and uniform distribution with a special network structure. The maximum tensile strength of welded joints can reach 92% of the base metal under optimum welding parameters.
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Qi, Yun Lian, Li Ying Zeng, Wei Liu, Hua Mei Sun, Yu Du, She Wei Xin, Wei Li Tan, and Si Yuan Zhang. "Effect of Extrusion Temperature and Thermal Treatment on Microstructure and Mechanical Properties of Ti-1300 Alloy Tube." Materials Science Forum 1016 (January 2021): 1181–87. http://dx.doi.org/10.4028/www.scientific.net/msf.1016.1181.
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Effects of extrusion temperature and heat treatment process on the microstructure and mechanical properties of Ti-1300 titanium alloy tube billets were studied by tensile testing and microstructure observation, and the relationship among the thermal processing technique and microscopic structure and mechanical properties of the billets were also investigated. The results showed that the transverse structure of Ti-1300 alloy after extrusion in the a+b two-phase region was uniform and fine. And the longitudinal structure could be seen that the extrusion processing streamline was broken uniformly. Ti-1300 alloy extruded at a+b two-phase has a good match of the strength and ductility, and the ductility of two-phase extrusion is obviously better than that of β single-phase extrusion, especially for the reduction of area.
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Zhai, Hui, and Yujin Zhai. "Optimization Design of Ferry Material Performance Test System Based on Artificial Intelligence." Journal of Nanomaterials 2022 (April 30, 2022): 1–10. http://dx.doi.org/10.1155/2022/2114377.
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Lead titanate in titanium-titanium mine and lead (solid solution optimized ferroelectric) is one of the most widely used multifunctional material systems, and they are outside the field (such as light, electricity, and heat) Structure, domain, and phase evolution characteristics are important for ferroelectric, piezoelectric, photoelectric, and memory applications. Functional materials are those high-tech materials with excellent electrical, magnetic, optical, and thermal functions, special physical, and chemical and biological effects, capable of completing functional interconversion, mainly used to manufacture various functional components and are widely used in various high-tech fields. This paper mainly analyzes iron and electrical materials and artificial intelligence technology by studying the characteristics of ferroelectric materials and research status at home and abroad and using artificial intelligence technology and the calculation of ferroelectric materials for artificial intelligence technology and Dexie optimization model. Artificial intelligence is a new technical science that studies and develops theories, methods, technologies, and application systems for simulating, extending, and expanding human intelligence. For artificial intelligence before the optimization of the hardware and software of the ferroelectric material performance test system, the optimized system is performed; the optimized system is subjected to safety testing; all test results show that the performance test of the ferroelectric material after optimization. The system data is well operating, and the artificial intelligence technology is suitable for optimization of the performance test system of ferroelectric material.
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Muhammad Irfan, Badaruddin Soomro, Bilal Waseem, Sumaira Nosheen, and Abdul Karim Aziz. "Microstructural effects of the substrate on adhesion strength and mechanical properties of TiN Thin Films." International Journal of Science and Research Archive 1, no. 2 (December 30, 2020): 022–31. http://dx.doi.org/10.30574/ijsra.2020.1.2.0037.
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Microstructure of base material plays an important role in adhesion strength and mechanical properties of Titanium Nitride (TiN) coating especially to increase the lifecycle of parts when in practical use. Present study covers the influence of grain size/microstructure of plain carbon steel (tailored via heat treatment) on TiN thin films deposited by physical vapor deposition (PVD) technique. Strong effect of grain size (microstructure) on adhesion strength of TiN thin films on annealed, normalized and quenched substrates have been observed. Mechanical characterization of TiN films e.g. Elastic modulus (E), Hardness (Hv), Stiffness (S) etc. have been studied via nano-indentation technique. TiN thin films failure investigation has been performed with Micro scratch testing under progressive load. Film exfoliation under critical loads has been corroborated via scanning electron microscopy (SEM). The results showed that TiN films deposited on fine microstructure substrate possess excellent mechanical properties and good adhesion strength as compared to coarser microstructure substrate. Insights of this study might be helpful in designing engineered thin films on optimized microstructures.
Dissertations / Theses on the topic "Titanium, Effects of heat on; Titanium – Testing"
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Linder, Noomi. "Understanding Effects of Isothermal Heat Treatments on Microstructure of LMD-w Titanium Alloy (Ti-6242) : On solution heat treated microstructure." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-80121.
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The use and knowledge of additive manufacturing technologies are rapidly growing. It is crucial to understand the processing-structure-property relationship, which is highly discussed when trying to understand the science of a material. One commonly used material in aerospace applications is titanium alloy, lately Ti-6Al-2Sn-4Zr-2Mo (Ti-6242). This work is addressed towards a laser metal deposition wire (LMD-w) manufactured Ti-6242 built on a Ti-6Al-4V (Ti-64) base plate. The microstructure of titanium alloys, like all other alloys, are highly dependent on its thermal history. It is crucial to understand the microstructural change in order to optimize the material properties. The prediction of microstructure through simulation can be improved by obtaining experimental input. Since the microstructure of an LMD-w manufactured component is different from the subtractive manufactured, the change from heat treatments are different considering the different start structures. It is therefore of interest to analyse isothermal heat treatments effect on solution heat treated microstructure of LMD-w Ti-6242, from an industrial application point of view. The objective of this work is to analyse the effect of isothermal heat treatment on microstructural changes for LMD-w Ti-6242 wall. The as received state was solution heat treated according to GKN standard, isothermal treatments were additionally performed and the change was analysed with microstructural characterization. The prior beta grain size, alpha lath thickness, phase fraction and hardness have been measured. Focus has been on the Ti-6242 wall for the measurements of alpha lath thickness and phase fraction. However, an analysis of the interface and heat affected zone (HAZ) has been made as well. MIPAR, an image analysis program was used for alpha lath thickness and phase distribution measurements. It has been concluded that the hardness of the material increases with increasing isothermal temperature during heat treatment and that the lath thickness increases with longer holding time. An equilibrium diagram has been obtained for Ti-6242 from a solution heat treated microstructure of LMD-w between the temperatures of 700°C and 1000°C and a time-temperature-transformation diagram (TTT-diagram), in the range of 700°C-1000°C and a holding time from 30 seconds to 2 hours.Efterfrågan av samt kunskapen om additiva tillverkningsmetoder ökar kraftigt. Det är därför av stort intresse att förstå relationen mellan process-struktur-egenskaper, vilket ofta diskuteras för att förstå vetenskapen bakom ett material. Ti-6Al-2Sn-4Zr-2Mo (Ti-6242) har under den senaste tiden väckt stort ett intresse inom flygindustrin. I detta arbete har fokus lagts på laser metal deposition wire (LMD-w) tillverkat material bestående av en Ti-6242 vägg på en Ti-64 basplatta. Titanlegeringars mikrostruktur är känslig mot den termiska historiken inom materialet. Det är därför av stort intresse att förstå hur mikrostrukturen ändras för att kunna optimera materialet. Förutberäkning genom simulering av mikrostrukturens förändring kan förbättras med hjälp av experimental indata. Eftersom mikrostrukturen av en LMD-w tillverkad komponent är annorlunda från traditionella tillverkningsmetoder, kommer förändringen av mikrostrukturen från värmebehandlingar vara olika, eftersom ursprungsstrukturen inte är densamma. Därför är det av intresse att analysera isotermiska värmebehandlingars påverkan på en upplösningsbehandlad mikrostruktur tillverkad med LMD-w, från en industriell synpunkt. Målet med detta arbete är att analysera effekten av isotermisk värmebehandling på mikrostrukturen av en LMD-w Ti-6242 vägg. Startmaterialet bestod av ett upplösningsbehandlat tillstånd enligt GKN standard, isotermiska värmebehandlingar gjordes och förändringen analyserades genom mikrostrukturkarakterisering. Primära beta korn, alfaband, fasfraktion och hårdhet har mätts. Fokus har legat i Ti-6242 väggens mätningar av alfaband och fasfraktion, dock har en analys av den värmebehandlade zonen (HAZ) i basplattan gjorts. MIPAR, ett bildanalysprogram, har använts för att mäta alfaband och fasdistribution. Det kan konstateras att hårdheten av materialet ökar med ökande isotermisk temperatur under värmebehandling, och att alfabandens tjocklek ökar med längre hålltider. Ett jämnviktsdiagram har framtagits för upplösningsbehandlad Ti-6242 LMD-w mellan temperaturerna 700°C och 1000°C. Ett tid-temperatur-transformations diagram (TTT-diagram) inom intervallet av 700°C-1000°C och från 30 sekunder till 2 timmar.
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Burke, Thomas. "AN SEM INVESTIGATION INTO THE EFFECTS OF CLINICAL USE ON HEAT-TREATED NICKEL-TITANIUM ROTARY ENDODONTIC FILES." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1470239374.
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Zapoticla, Frank. "The Effects of Applied Strain and Heat Treatment on the Properties of NiTi Wire During Shape Setting." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/378.
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NiTi components are commonly subjected to thermo-mechanical heat treatments during production and fabrication. This study investigates the effects of applied strain of 0-10% and heat treatments of 300-600ºC for times of 2-30 minutes during shape-setting of Ti–50.8 at% Ni wire with a nominal diameter of 0.495 mm and an initial transition temperature, Af, of 12ºC. Strain was applied prior to heat treatments by coiling NiTi wire, essentially producing coiled springs, around different diameter steel mandrels to obtain different strain levels. The samples of NiTi wire under applied strain were heat treated in a salt bath, followed by a rapid quench. Transformation temperatures and mechanical properties were characterized using the differential scanning calorimeter and tensile tests. Changes in the Af, UTS, and elastic modulus due to ageing processes and applied strain were observed. Following theory, precipitation rates of Ni-rich phases generally increased with increased temperature (up to a certain point), time and applied strain levels. Reaction rates to achieve a particular Af might be faster than expected if the sample is under strain during the shape-setting process. Due to precipitation strengthening, an increase in UTS with increased heat treatment time was observed between 300-450°C; annealing processes dominate at higher temperatures, resulting in a decrease in UTS above 500°C. A decrease in UTS with increasing level of applied strain was observed. Trends in elastic modulus were highly inconsistent in this study. As shown by this study, applied strain in NiTi during heat treatment affects the Af and mechanical properties.
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Kassam, Tahsin Ali. "The effects of Alumina purity, TICUSIL® braze preform thickness and post-grinding heat treatment on the microstructure, mechanical and nanomechanical properties of Alumina-to-Alumina brazed joints." Thesis, Brunel University, 2017. http://bura.brunel.ac.uk/handle/2438/15311.
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Alumina-to-alumina brazed joints were formed using 96.0 and 99.7 wt.% Al2O3 ceramics in as-ground and in ground and heat treated conditions using TICUSIL® (68.8Ag-26.7Cu-4.7Ti wt.%) braze preforms of thicknesses ranging from 50 to 250 μm. Brazing was conducted in a vacuum of 1 x 10-5 mbar at 850 °C for 10 minutes. Joint strengths were evaluated using four-point bend testing and were compared to the flexural strengths of standard test bars according to ASTM C1161-13. Post-grinding heat treatment, performed at 1550 °C for 1 hour, did not affect the average surface roughness or grain size of either grade of alumina but affected their average flexural strengths, with a small increase for 96.0 wt.% Al2O3 and a small decrease for 99.7 wt.% Al2O3. Post-grinding heat treatment led to secondary phase migration, creating a fissured 96.0 wt.% Al2O3 surface. This affected the reliability of 96.0 wt.% Al2O3 brazed joints, in which braze infiltration was observed. As the TICUSIL® braze preform thickness was increased from 50 to 150 μm, the average strengths of both 96.0 and 99.7 wt.% Al2O3 brazed joints improved. This occurred due to a microstructural evolution, in both sets of joints, which was studied using SEM, TEM and nanoindentation techniques. An increase in the TICUSIL® braze preform thickness increased the amount of Ti which was available to diffuse to the joint interfaces. This led to increases in both, reaction layer and braze interlayer thicknesses. Excess Ti in joints that were made using TICUSIL® braze preforms thicker than 50 μm, led to relatively hard Cu-Ti phases in an Ag-Cu braze interlayer. Cu-Ti phase formation, which may have reinforced joint strength whilst also reducing CTE mismatch at the joint interface, also led to Ag-rich braze outflow at the joint edges. Brazed joints made using as-ground 96.0 wt.% Al2O3 consistently outperformed brazed joints made using as-ground 99.7 wt.% Al2O3, due to the formation of Ti5Si3 phases at locations where the Ti-rich reaction layer intersected with the triple pocket grain boundary regions of the as-ground 96.0 wt.% Al2O3 surface.
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Juratovac, Joseph M. "Strain Rate Sensitivity of Ti-6Al-4V and Inconel 718 and its Interaction with Fatigue Performance at Different Speeds." Ohio University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1605875502029283.
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MacLeod, David Matthew. "The Mechanical Effects of Flaming Nickel-titanium Orthodontic Archwires." Thesis, 2011. http://hdl.handle.net/1807/31327.
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Objective: To assess the mechanical effects of nickel-titanium orthodontic archwire flaming and their distribution along the wire. Methodology: Two sizes of pre-formed austenitic nickel-titanium archwires were tested (n=10). The terminal 5mm of each wire was heated for five seconds using a butane lighter. Micro-hardness testing was used to determine the heat-affected zone for all wires. Cantilever bending was performed to assess the mechanical properties of heated wires. Results: The heat-affected zone was found to extend less than 2 mm past the flame boundary for all wires. For each wire gauge, the flamed zone was characterized by a lower and flatter super-elastic plateau and an increased tendency for plastic deformation when compared to controls. Conclusions: The limited ability of austenitic nickel-titanium orthodontic archwires to conduct heat past the boundary of the flamed region suggests no need to alter current clinical practice.
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Lian, Jun-Jie, and 連俊傑. "Effects of heat treatments on the anodized titanium with Ag+ addition." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/p8fzus.
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碩士國立臺北科技大學
材料科學與工程研究所
103
Titanium and its alloys are widely for fabrication of orthopedic due to their good biocompatibilty. Because the lack of desirable bioactive properties of Ti metal, we need to do surface modification to make implant even better osseointegration. Let Ag+ being adsorbed on Ti surface to have antibacterial activity. Pure Ti specimens were coated nanotubes by anodization at 10℃ from the electrolyte mixtures of NaSO4 and NH4F. Then do different heat treatment and put into Silver nitrate solution for 24 hours. A series of electrochemical analysis techniques to investigate the behavior of the specimens in Hank&;#39;s solution. The surface morphology, structural and chemical compositions properties of the samples were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS). Finally, the electrochemical characteristics were investigated by open circuit voltage (OCV)、tafel interpolation and electrochemical impedance spectroscopy (EIS).
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Mawanga, Philip. "An investigation on the effects of high speed machining on the surface integrity of grade 4 titanium alloy." Thesis, 2012. http://hdl.handle.net/10210/5394.
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M.Ing.Grade 4 titanium is a commercially pure grade titanium alloy extensively used in various industries including the chemical industry and more recently in the biomedical industry. Grade 4 has found a niche as a biomedical material for production of components such as orthopaedic and dental implants. Its physical properties such as high corrosion resistance, low thermal conductivity and high strength make it suitable for these applications. These properties also make it hard-to-machine similar to the other grades of titanium alloys and other metals such as nickel based alloys. During machining of titanium, elevated temperatures are generated at the tool-workpiece interface due to its low thermal conductivity. Its high strength is also maintained at these high temperatures. These tend to impair the cutting tool affecting its machinability. Various investigations on other grades of titanium and other hard-to-machine materials have shown that machining at high cutting speeds may improve certain aspects of their machinability. High speed machining (HSM) is used to improve productivity in the machining process and to therefore lower manufacturing costs. HSM may, however, change the surface integrity of the machined material. Surface integrity refers to the properties of the surface and sub-surface of a machined component which may be quite different from the substrate. The properties of the surface and sub-surface of a component may have a marked effect on the functional behaviour of a machined component. Fatigue life and wear are examples of properties that may be significantly influenced by a change in the surface integrity. Surface integrity may include the topography, the metallurgy and various other mechanical properties. It is evaluated by examination of surface integrity indicators. In this investigation the three main surface integrity indicators are examined. These are surface roughness, sub-surface hardness and residual stress. White layer thickness and chip morphology were also observed as results of the machining process used. The effect of HSM on the surface integrity of grade 4 is largely unknown. This investigation therefore aims to address this limitation by conducting an experimental investigation on the effect of HSM on selected surface integrity indicators for grade 4. Two forged bars of grade 4 alloy were machined using a CNC lathe at two depths of cut, 0.2mm and 1mm. Each bar was machined at varying cutting speeds ranging from 70m/min to 290m/min at intervals of approximately 20m/min. Machined samples were prepared from these cutting speeds and depths of cut. The three surface integrity indicators were then evaluated with respect to the cutting speed and depth of cut (DoC). iv Results show that a combination of intermediate cutting speeds and low DoC may have desirable effects on the surface integrity of grade 4. Highest compressive stresses were obtained when machining with these conditions. High compressive stresses are favourable in cases where the fatigue life of a material is an important factor in the functionality of a component. Subsurface hardening was noticed at 0.2mm DoC, with no subsurface softening at all cutting speeds. Surface hardness higher than the bulk hardness tends to improve the wear resistance of the machined material. Though surface roughness values for all depths of cut were below the standard fine finish of 1.6μm, roughness values of samples machined at 0.2mm DoC continued to decrease with increase in cutting speed. Low surface roughness values may also influence the improvement of fatigue life of the machined components. These machining conditions, (intermediate cutting speeds and low DoC), seem to have promoted mechanically dominated deformation during machining rather than thermal dominated deformation. Thermal dominated deformation was prominent on titanium machined at DoC of 1mm.
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Wu, Cheng-Lin, and 吳政霖. "Process temperature and Heat Treatment Titanium nitride (TiN) effects of thin film of mechanical properties." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/36055012223718520890.
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碩士元智大學
機械工程學系
98
Titanium nitride thin films with high hardness, high strength and abrasion resistance, and many other advantages, suited as a material or structure of the surface protection layer ideally, such as the cutting tool. In this paper, magnetron sputtering machine in SU304 stainless steel substrate surface, sputtering titanium nitride film to explore the temperature process and heat treatment temperature on the mechanical properties of titanium nitride films include the effect of hardness, Young''s modulus and corrosion rate. And another with atomic force microscopy and surface profiler observation of film surface morphology and roughness of micro-structure, energy dispersive spectroscopy analyzer titanium nitride film element. The temperature selected with room temperature 25℃, 100℃, 200℃, 300℃. Through nano-indentation test results show that thin-film hardness, as the process temperature and tempering temperature increases. Detection of resistance to the corrosive character of electrochemical results showed that the corrosion rate of titanium nitride thin films with the process temperature and tempering temperature increases. Heating process to make titanium nitride molecules in the deposition process for a larger kinetic energy, accumulated of the dense film has a better on film than to improve the mechanical properties of the heat treatment.
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Chen, Bor-Yuan, and 陳柏源. "Effects of β Stabilizers and Heat Treatment on the Mechanical Properties and Microstructure of α + β Titanium Alloys." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/24971483623710934171.
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博士國立臺灣大學
材料科學與工程學研究所
100
Powder metallurgy (PM) titanium alloys have been widely applied in the automobile, military, and biomedical industries due to its high specific strength, excellent corrosion and oxidation resistance, moderate strength at high temperatures, good biocompatibility, and low manufacturing cost. This study examined the sintered properties of gas atomized pure titanium powder and titanium hydride powder. The gas atomized powder exhibited the best results. Also investigated are the effects of Nb, Ta, Mo, Si, Cu, Ni, Fe (CM carbonyl iron powder), Co, and Sn alloying powders on the mechanical properties and microstructures of α + β titanium alloys. The results indicated that all sintered alloys reached relative densities of 95% or higher, and the contents of carbon and oxygen were low at 0.10 and 0.40 wt%, respectively. The sintered Ti-7Fe using furnace cooling followed by fan cooling had a high tensile strength of 916 MPa, and the elongation was 13%. These properties are similar to those of the annealed wrought Ti-6Al-4V. With isothermal holding at 740 ℃ for 24 hours prior to fan cooling, the tensile strength further increased to 976 MPa, and the elongation was 12%. Moreover, Ti-7Fe-5Sn showed the best tensile properties in ternary systems with about 1077 MPa tensile strength and 6% elongation. The results suggest that large amounts of β phase with high iron content and fine precipitates within β phase will provide a good combination of strength, hardness, and elongation. For TiC/Ti-7Fe alloys, the highest tensile strength (1007 MPa) and hardness (34 HRC) were produced by using pure titanium and OS carbonyl iron powders due to the presence of in situ formed TiC, and SiO2 particles in the as-received OS iron powder.
Books on the topic "Titanium, Effects of heat on; Titanium – Testing"
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Fisher, G. T. Effects of composition and processing variables on transverse rupture strength and hardness of nickel-alloy-bonded titanium carbide. Pittsburgh, Pa: U.S. Dept. of the Interior, Bureau of Mines, 1987.
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Lampman, Steve, ed. Weld Integrity and Performance. ASM International, 1997. http://dx.doi.org/10.31399/asm.tb.wip.9781627083591.
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Weld Integrity and Performance is a convenient reference and sourcebook for anyone involved in the application, fabrication, or assessment of welded structures. It provides detailed information on relevant topics including weld solidification, weldability testing, weld characterization, discontinuities and imperfections, cracking phenomena, inspection and evaluation techniques, fatigue and fracture control, fracture mechanics, fitness-for-service testing, repair welding, and weld corrosion. An entire section, the largest by far in the book, covers the basic metallurgy and engineering properties of weldments made from carbon and low-alloy steels, stainless steels, aluminum alloys, titanium alloys, nickel-base alloys, and refractory metals, including tantalum, niobium, molybdenum, and tungsten alloys. The book also provides insights into the origins of failure associated with different welding processes and includes an appendix with information on the weldability of common alloys (including cast irons) as well as process selection guidelines, recommended preheat and interpass temperatures and postweld heat treatments for pipe welds and pressure vessels, and qualification codes and standards. For information on the print version, ISBN 978-0-87170-600-8, follow this link.
Book chapters on the topic "Titanium, Effects of heat on; Titanium – Testing"
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Huang, Lujun, and Lin Geng. "Effects of Heat Treatment on Microstructure and Properties of TiBw/Ti6Al4V Composites." In Discontinuously Reinforced Titanium Matrix Composites, 109–22. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-4449-6_6.
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"Properties of Titanium-Alloy Welds." In Weld Integrity and Performance, 311–27. ASM International, 1997. http://dx.doi.org/10.31399/asm.tb.wip.t65930311.
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Abstract This article discusses the fusion welding processes that are most widely used for joining titanium, namely, gas-tungsten arc welding, gas-metal arc welding, plasma arc welding, laser-beam welding, and electron-beam welding. It describes several important and interrelated aspects of welding phenomena that contribute to the overall understanding of titanium alloy welding metallurgy. These factors include alloy types, weldability, melting and solidification effects on weld microstructure, postweld heat treatment effects, structure/mechanical property/fracture relationships, and welding process application.
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Khalil, Hammad, Tehseen Zahra, Zaffer Elahi, and Azeem Shahzad. "Effect of Titanium Oxide Nanofluid over Cattaneo-Christov Model." In Functional Calculus - Recent Advances and Development [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.106900.
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The proposed chapter deals with the study of heat transfer development of titanium oxide nanofluid of platelet shape nanoparticles over a vertical stretching cylinder. The set of nonlinear equations is obtained using suitable transformation on the governing equations that are then solved with numerical scheme BVP4C. The obtained results are interpreted graphically and numerically. The effects of Prandtl, Eckert, and unsteadiness parameters on temperature distribution are depicted. Moreover the skin friction and Nusselt number are also computed.
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"Effects of Machining Process and Heat Treatment on the Mechanical Properties and Microstructure of TB2 Titanium Alloy Strip." In Materials in Environmental Engineering, 25–32. De Gruyter, 2017. http://dx.doi.org/10.1515/9783110516623-002.
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Rauf, Adil, Syed Husain Imran Jaffery, Mushtaq Khan, Najam ul-Qadir, Shamraiz Ahmed, and Danyal Zahid. "Effects of Machining Parameters on Feed Direction Cutting Forces in Meso-Scale End-Milling of Ti-6Al-4V Under Dry, Wet and MQL Environment." In Advances in Transdisciplinary Engineering. IOS Press, 2022. http://dx.doi.org/10.3233/atde220582.
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High strength, resistance to corrosion, small density and remarkable strength to weight ratio of titanium distinguish it from other metals and is a reason for its use in in renowned industrial setups like bio-medical, automotive, aeronautics, and power generation industries. However, these are considered as difficult-to-machine elements because of less heat conductivity, minimum value of modulus of elasticity, substantial chemical reactivity and elevated temperature strength. Ti-6Al-4V is regarded as major industrial alloy and a focus of research studies. Measurement and analysis of machining forces provides a deep insight into the mechanics of machining and assist in understanding machinability, tool wear / fracture, machining precision, chatter stability, energy, surface quality and temperature. This further helps in finding optimum machinability parameters for different materials. Machining forces are affected by a number of factors including cutting conditions and lubrication / cooling environment. In this research, analysis of milling forces under three different lubrication / cooling environments i.e. Dry, Wet and MQL (Minimum Quantity Lubrication) along with effects of milling parameters during meso-scale milling of Ti-6Al-4V has been conducted. End milling experiments have been performed basing on Taguchi L9 orthogonal array for optimal combination of milling parameters, keeping spindle speed, depth of cut, feed per tooth and cooling conditions as the control factors. Contribution ratios of different milling parameters and lubrication / cooling environment on feed direction forces have been analyzed through ANOVA.
Conference papers on the topic "Titanium, Effects of heat on; Titanium – Testing"
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Mjali, Kadephi V., Annelize Els-Botes, and Peter M. Mashinini. "The Effects of Laser and Mechanical Forming on the Hardness and Microstructural Layout of Commercially Pure Grade 2 Titanium Alloy Plates." In ASME 2017 12th International Manufacturing Science and Engineering Conference collocated with the JSME/ASME 2017 6th International Conference on Materials and Processing. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/msec2017-2603.
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This paper illustrates the effects of the laser and mechanical forming on the hardness and microstructural distribution in commercially pure grade 2 Titanium alloy plates. The two processes were used to bend commercially pure grade 2 Titanium alloy plates to a similar radius also investigate if the laser forming process could replace the mechanical forming process in the future. The results from both processes are discussed in relation to the mechanical properties of the material. Observations from hardness testing indicate that the laser forming process results in increased hardness in all the samples evaluated, and on the other hand, the mechanical forming process did not influence hardness on the samples evaluated. There was no change in microstructure as a result of the mechanical forming process while the laser forming process had a major influence on the overall microstructure in samples evaluated. The size of the grains became larger with increases in thermal gradient and heat flux, causing changes to the overall mechanical properties of the material. The thermal heat generated has a profound influence on the grain structure and the hardness of Titanium. It is evident that the higher the thermal energy the higher is the hardness, but this only applies up to a power of 2.5kW. Afterwards, there is a reduction in hardness and an increase in grain size. The cooling rate of the plates has been proved to play a significant role in the resulting microstructure of Titanium alloys. The scanning speed plays a role in maintaining the surface temperatures of laser formed Titanium plates resulting in changes to both hardness and the microstructure. An increase in heat results in grain growth affecting the hardness of Titanium.
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Shepherd, Dominique A., and Vijay K. Vasudevan. "The Effect of Molybdenum on the Creep Behavior of Orthorhombic Titanium Aluminides." In ASME Turbo Expo 2002: Power for Land, Sea, and Air. ASMEDC, 2002. http://dx.doi.org/10.1115/gt2002-30660.
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The effect of molybdenum additions on the creep properties of two orthorhombic titanium aluminide materials, Ti-22Al-26Nb and Ti-22Al-24.5Nb-1.5Mo (% atomic fraction), has been investigated. Heat treatments below the beta transus temperature followed by a 16-hour ageing treatment produced similar microstructures. Using the similar microstructures (consisting of O laths in a B2 matrix with α2 dispersed at B2 grain boundaries) for the two compositions, tensile creep testing was conducted under stresses of 68 MPa, 160 MPa, and 197 MPa at temperatures of 590 °C and 760 °C. The creep results demonstrated the favorable effects of Mo on creep resistance in these orthorhombic titanium aluminides. Due to similar microstructures, results also suggested that improvements have been substructural, rather than purely microstructural, in nature.
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Predki, Wolfgang, and Bjo¨rn Bauer. "Safety Clutches With Nickel-Titanium Shape Memory Alloys." In ASME 2009 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. ASMEDC, 2009. http://dx.doi.org/10.1115/smasis2009-1262.
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The ability of Shape Memory Alloys (SMA) to remind two different macroscopic shapes and to alter between these shapes by changing their temperature, leads to innovative approaches within drive technology. Especially Nickel-Titanium (NiTi) Shape Memory Alloys offer high actuating forces and adjustment travel in combination with high cycle stability. The shape memory effect is based on the transformation between martensitic and austenitic microstructure depending on the temperature of the actuators. The transformation temperatures in the range of 20°C to 100°C make NiTi SMA attractive for engineering applications. This paper investigates the technical use of NiTi SMA as actuators within a safety clutch. Safety clutches serve in power trains as torque limiting elements with the aim to prevent destruction of the working machine or the motor. Based on the concept of a friction clutch the conceptual design of the NiTi safety clutch is developed and followed by the design and manufacturing of a prototype. The activation of the NiTi actuators occurs as a result of the frictional heat at the friction pads when the torque limit is exceeded and the clutch slips. The actuators transform from martensitic to austenitic condition. Their stiffness increases so that the actuators are able to open the clutch. This leads to a complete collapse of the torque. During the cooling phase the transformation from austenite to martensite occurs and the NiTi actuators are deformed again. The friction pads are clamped with their original force and the clutch is able to transmit the demanded torque. The mechanical dimensioning of the actuator system is figured out as well as the measurement results of the analysis on the testing bench. The variation of the input parameters like torque and speed and the variation of the actuator system itself show possibilities and frontiers of this technology.
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Celli, Dino A., Justin Warner, Onome Scott-Emuakpor, and Tommy George. "Investigation of Self-Heating During Ultrasonic Fatigue Testing and Effect on Very High Cycle Fatigue Behavior of Titanium 6Al-4V." In ASME Turbo Expo 2022: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/gt2022-83443.
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Abstract Very high cycle fatigue (VHCF) data and experiments, 107−109 cycles to failure, has traditionally been both a cumbersome and costly task to perform. However, characterizing VHCF behavior of material systems are critical for the design and sustainability of turbine engines as outlined in the turbine engine structural integrity program (ENSIP). With recent advancements, ultrasonic fatigue test systems have become increasingly available to generate VHCF fatigue data. A primary consideration for ultrasonic fatigue testing is the frequency of loading, the resulting thermal evolution, and its effect on fatigue life. To mitigate the heat generation within the specimen during experiments, cooling air is directed to the specimen and cyclic loading is performed by selecting an appropriate test frequency or defining a duty cycle rather than continuously subjected to fatigue. However, standardization of experimental test procedures remains ongoing and continues to be developed. In this study a Shimadzu USF-1000A ultrasonic fatigue test system is used to characterized VHCF behavior of Ti 6Al-4V to understand the effect of duty cycle and thermal evolution on fatigue life for ultrasonic fatigue testing. Titanium 6Al-4V test specimens are subjected to fully reversed axial fatigue at 20kHz exciting resonance in an axial mode to better characterize the experimental process. Three duty cycle configurations are investigated and its effect on fatigue life due to self-generated heat during the experiment. Heat generation is monitored in-situ via a single-point optical pyrometer and in-situ mechanical and thermal data is collected and compared to standardized servo-hydraulic fatigue test data performed in this study as well as from data found in the literature.
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Pavel, Radu, and Anil K. Srivastava. "Investigations for Safe Grinding of Ti-6Al-4V Parts Produced by Direct Metal Laser Sintering (DMLS) Technology." In ASME 2014 International Manufacturing Science and Engineering Conference collocated with the JSME 2014 International Conference on Materials and Processing and the 42nd North American Manufacturing Research Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/msec2014-4130.
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Direct Metal Laser Sintering (DMLS) is an additive manufacturing technology that can construct medium to small size parts very efficiently in comparison to traditional machining processes. The ability of this technology to grow complex parts made of high strength titanium- and nickel-based alloys led to increasing interest from aerospace, defense, and medical industries. Although the technology allows growing parts close to their final shape, the active surfaces still need a finishing operation such as grinding to meet the tight tolerances and surface finish requirements. Due to the novelty of the DMLS technology, and the relatively recent developments of titanium alloy powders, there is a need for testing and validating the capabilities of the components manufactured through a combination of DMLS and grinding processes. This paper presents the findings of an experimental study focused on the effect of various grinding conditions on the surface integrity of titanium alloy (Ti-6Al-4V) specimens produced using DMLS technology. The goal is to identify dressing and grinding conditions that would result in ground surfaces free of defects such as micro-cracks, discoloration of surfaces and/or burn marks due to high heat generated during grinding. The residual stresses were used to quantify the effect of the grinding conditions on the ground surfaces. These investigations were conducted on an instrumented CNC surface grinding machine, using a silicon-carbide grinding wheel and a water-based fluid. The X-ray diffraction method was used to measure the residual stresses. Two batches of specimens were manufactured for these tests. The growing strategy of the specimens and the presence of apparent defects in material structure are considered some of the main causes for the differences observed in the outcomes of the grinding trials. The results of these investigations support the need for continuing research in the additive manufacturing field to develop methods and technologies that will ensure a high level of consistency of the grown parts.
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Dussinger, Peter, William Anderson, and Eric Sunada. "Design and Testing of Titanium-Cs and Titanium-K Heat Pipes." In 3rd International Energy Conversion Engineering Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2005. http://dx.doi.org/10.2514/6.2005-5631.
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Fonte, Matthew, and Anil Saigal. "Tension-Compression Asymmetry of Solid, Shape Recovered “Bulk” Nitinol." In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-11411.
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As the shape memory material Nitinol (55% Nickel – 45% Titanium alloy) emerges to find more and more applications in engineered products, understanding the effects of material processing becomes increasingly important. Its mechanical behavior is highly non-linear and is strongly dependent on alloy composition, heat treatment history and mechanical work. Published Nitinol literature is almost exclusively related to processing and testing of thin wall, very small diameter tubing and wire devices, usually exhibiting superelastic characteristics. In strain-controlled tension-compression testing of pseudoelastic Nitinol shape memory wires, compression recovery forces were found to be markedly higher than tension forces. However, most experimental studies of the thermomechanical behavior of Nitinol (NiTi) to date have been conducted in uniaxial tension on wire devices. There is a dearth of information in the literature regarding the compression recovery of solid blocks of Nitinol. Questions exist on whether or not solid, “bulk” Nitinol products when deformed in compression will exhibit shape recovery characteristics? The potential for shape recovery of compressed solid blocks of Nitinol products, which could have large stress-strain outputs, can enable the design of novel devices in many industries. The motivation for this research is to provide the first characterization of the shape recovery effects of “bulk” Nitinol material under compressive deformation modes versus the often practiced and well understood tensile loading of wire and thin wall tubing.
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Schmidt, Marvin, Andreas Schütze, and Stefan Seelecke. "Experimental Investigation on the Efficiency of a Control Dependent NiTi-Based Cooling Process." In ASME 2014 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/smasis2014-7561.
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Energy efficient systems and environmentally friendly solutions are the focus of many commercial development projects. Current refrigeration technology carries a significant share of global energy consumption and exploring alternative refrigeration principles has become increasingly important. Shape memory alloys (SMA’s), especially Nickel-Titanium (NiTi) alloys, generate a large amount of latent heat during solid-state phase transformations, which can lead to a significant cooling effect in the material. These materials not only provide the potential for an energy efficient cooling process, they also minimize the impact on the environment by reducing the need for conventional ozone-depleting refrigerants. This paper presents the first experimental results obtained in a project within the DFG Priority Programme SPP 1599 “Ferroic Cooling”. It focuses on the performance of a control-dependent process of a NiTi-based cooling system. First, a suitable cooling process is introduced and the underlying mechanisms of the process are explained. Then different process variations are developed, which influence the efficiency of the cooling process. These process variations are systematically analyzed with a novel, experimental testing system capable of tuning process parameters independently. The testing system is able to measure force, displacement, temperature distribution and heat simultaneously. The coefficient of performance (of the cooling process) can then be determined by which the influence of the control process on the efficiency can be observed.
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Wang, Zhengdong, Changjun Liu, Fu-Zhen Xuan, and Shan-Tung Tu. "Determination of Material Degradation at Various Environmental Conditions." In ASME 2011 Pressure Vessels and Piping Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/pvp2011-57570.
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There are growing interests in materials and system degradation at various environmental conditions, especially for structures in fossil fuel power station, nuclear power plants and petrochemical industry. Several testing and simulation approaches have been developed to determine the degradation of material properties with the influence of corrosion environment. A simulation technology is introduced to investigate the effects of irradiation on mechanical properties for a degraded reactor pressure vessel steel. The degradation procedure combines the application of cold prestrain together with high temperature heat treatment. It is found from the results of Charpy impact tests for degraded material that there is an increase of ductile-brittle transition temperature and a trend to a decrease of upper shelf energy because of irradiation embrittlement. Evaluation procedures of temper embrittlement and hydrogen-embrittlement are described for reactor pressure vessel steel exposed to hydrogen environment. A regular coupon sample test is adopted to determine the material degradation of hydrogen processing reactors. Numerical analysis and experimental hydrogen charging technique are explored to simulate the process of hydrogen embrittlement. A critical parameter of hydrogen concentration is defined to evaluate the susceptibility of hydrogen induced cracking for reactor steels. A fatigue testing system is designed to obtain the degradation of fatigue strength for materials under the low oxygen steam environment. The system couples a steam chamber with an axial force-controlled fatigue testing machine. The fatigue tests are performed for a titanium alloy with tension-compression loading up to 107 cycles. Test results show that the fatigue strength is obviously influenced by the steam environment and the stress ratios.
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Wheeler, Robert, Judy Santa-Cruz, Darren Hartl, and Dimitris Lagoudas. "Effect of Processing and Loading on Equiatomic NiTi Fatigue Life and Localized Failure Mechanisms." In ASME 2013 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/smasis2013-3163.
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Shape Memory Alloys (SMAs) have many promising applications in the aerospace, automotive, and energy industries. However, due to a lack of understanding of their actuation fatigue, applications are sometimes limited to non-structural or non-critical components. This paper addresses the actuation fatigue characteristics of a specific SMA, equiatomic Nickel-Titanium (NiTi), with varying heat treatments, as well as different methods for assessing actuation fatigue response, including improved testing procedures and distributed extension measurement methods. Heat treatments ranged from 350°C to 400°C for one to three hours. Dogbone specimens processed from heat treated NiTi sheets were mechanically loaded on test frames which provided resistive heating and forced convective cooling with dry air via vortex tubes. Two mechanical loading schemes were utilized: constant uniaxial load (initial stress of 200MPa) and a linear or spring load centered at 200MPa (and ranging from approximately 150MPa to 250MPa). Linear loading schemes were introduced in order to better simulate actuation in an aerospace application, such as the morphing of semi-rigid surfaces. Specimens were thermally cycled to full actuation with a time-based control scheme developed in LabVIEW. Fatigue responses varied widely as a result of different heat treatments and loading schemes. Due to the main failure mechanism being high localized extension (necking) for the constant loading schemes, additional hardware and software were developed to visually capture extension distribution over specimen length. By analyzing actuation characteristics (e.g. transformation strain) and fatigue mechanisms, the ideal post-processing for actuator applications was determined. Utilizing the local extension distribution evolution over the fatigue life of NiTi specimens as well as postmortem analysis of the failure surfaces allowed for the failure modes to be determined for each heat treatment.