Статті в журналах: "Microstructural modification"

1

Abdalla, Ayad Omran, Astuty Amrin, Roslina Mohammad, and M. A. Azmah Hanim. "Microstructural Study of Newly Designed Ti-6Al-1Fe Alloy through Deformation." Solid State Phenomena 264 (September 2017): 54–57. http://dx.doi.org/10.4028/www.scientific.net/ssp.264.54.

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Recently, iron (Fe) is introduced to substitute vanadium (V) in Ti-alloy. Therefore, new (α+β) titanium alloy, Ti-6Al-1Fe was designed through a complete replacement of V by Fe with major composition modifications of Ti-6Al-4V. This new alloy is believed could provide similar properties of Ti-6Al-4V through modification of its microstructures. Different heat treatments can lead to a diversity of microstructural permutations and combinations. Thus, it is very crucial to study in-depth understanding about the microstructure of Ti-6Al-1Fe. Results reveal that the microstructure of as-received alloy is a typical fine lamellar microstructure. The bi-modal microstructure can be obtained by hot rolling below beta-transus temperature (Tβ) followed by recrystallization treatment at 925°C. While cold rolling followed by recrystallization treatment at 925°C produce equiaxed microstructure.

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2

Taltavull, Catalina, Belen Torres, Antonio Julio Lopez, and Joaquin Rams. "Relationship between Laser Parameters - Microstructural Modification - Mechanical Properties of Laser Surface Melted Magnesium Alloy AZ91D." Materials Science Forum 765 (July 2013): 678–82. http://dx.doi.org/10.4028/www.scientific.net/msf.765.678.

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Laser surface melting is a high-energy surface treatment that allows modification of the microstructure and surface properties of Mg alloys. In the present work, a high-power diode laser has been used to study the microstructural and mechanical modifications that occur when laser surface treatments are applied to the surface of the AZ91D Mg alloy. Laser-beam power in a range of 375-600 W and laser scanning speeds of 45-60-90 mms-1 has been used to develop a range of laser surface melting treatments. By controlling the laser parameters, two types of surface modifications can be obtained. Complete laser surface melting takes place at high laser input energies whilst at low laser input energies, selective laser surface melting occurs with modification of only one phase in the microstructure of the alloy; the other phase remained unaffected. In terms of mechanical properties, the microstructural modifications introduced by the laser surface treatment implied a hardness homogenization along the melted region.

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3

Herbster, Maria, Karsten Harnisch, Paulina Kriegel, Andreas Heyn, Manja Krüger, Christoph H. Lohmann, Jessica Bertrand, and Thorsten Halle. "Microstructural Modification of TiAl6V4 Alloy to Avoid Detrimental Effects Due to Selective In Vivo Crevice Corrosion." Materials 15, no. 16 (August 19, 2022): 5733. http://dx.doi.org/10.3390/ma15165733.

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TiAl6V4 wrought alloy is a standard material used for endoprostheses due to its ideal characteristics in terms of osseointegration. However, the insufficient wear and crevice corrosion resistance of TiAl6V4 are limiting factors that can cause clinical problems. Therefore, the objective of this study was to analyze and identify suitable phases and microstructural states of TiAl6V4 alloy with advantageous implant properties by thermal treatments. By varying the temperature and cooling rate, four heat treatment strategies were derived that produced different microstructural states that differed in morphology, arrangement and proportions of phases present. All TiAl6V4 modifications were characterized regarding their microstructure, mechanical, corrosive and tribological properties, as well as cell adhesion. The acicular, martensitic microstructure achieves a significant hardness increase by up to 63% and exhibits improved corrosion and wear resistance compared to the forged condition. Whereas the modified microstructures showed similar electrochemical properties in polarization tests using different electrolytes (PBS with H2O2 and HCl additives), selective α or β phase dissolution occurred under severe inflammatory crevice conditions after four weeks of exposure at 37 °C. The microstructurally selective corrosion processes resemble the damage patterns of retrieved Ti-based implants and provide a better understanding of clinically relevant in vivo crevice corrosion mechanisms. Furthermore, a microstructural effect on cell attachment was determined and is correlated to the size of the vanadium-rich β phase. These key findings highlight the relevance of an adapted processing of TiAl6V4 alloy to increase the longevity of implants.

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4

Jeong, G. C., H. J. Choi, Yong Ho Sohn, and S. I. Kwun. "Effects of Combined Surface Modification on Adhesion Strength of CrN Coatings for STS420." Defect and Diffusion Forum 297-301 (April 2010): 1334–39. http://dx.doi.org/10.4028/www.scientific.net/ddf.297-301.1334.

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In order to improve the durability and performance of molds and tools, diverse methods of surface modification are used where the adhesion strength between a substrate and coating plays an important role. To improve adhesion strength, a combined surface modification method is often utilized. In this study, adhesion strength and microstructure of various combined surface modifications (i.e., ion-nitriding, Cr intermediate layer, CrN layer and nitrogen ion- implantation) were examined on STS420. Phase constituents, microstructure, adhesion strength and hardness of coating-substrate system with combined surface modification were examined by using optical microscopy, X-ray diffraction, transmission electron microscopy, scratch test, and nano-indentation. The highest adhesion strength was observed when CrN coating was formed by nitrogen implantation on ion-nitrided substrate with a Cr-intermediate layer. Influence of processing sequence and combination is related to microstructural observations and adhesion strength.

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5

Liu, Z., H. Liu, F. Viejo, Z. Aburas, and M. Rakhes. "Laser-induced microstructural modification for corrosion protection." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 224, no. 5 (March 26, 2010): 1073–85. http://dx.doi.org/10.1243/09544062jmes1858.

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Laser surface modification of materials by melting and annealing has been the subject of considerable interest as a means of enhancing the corrosion performance of metallic alloys. Microstructural modification without changing surface chemical composition, in terms of homogenization/refinement of microstructures, dissolution/re-distribution of intermetallic particles, and extended solid solubility, resulting from rapid rates of cooling, provides the basis for property enhancement. This paper reviews authors’ work on laser surface melting (LSM) and laser annealing (LA) for the purpose of improved corrosion performance. Microstructural evolution and corrosion performance in a range of metallic alloys, followed by different treatments with different types of lasers, are presented. For LSM of aerospace aluminium alloys, the corrosion mechanisms of the laser-melted alloys have been discussed in the consideration of electrochemical characteristics of intermetallic particles with respect to the aluminium matrix and cooling rates leading to different degrees of refinement/removal of intermetallic particles. For LA of amorphous electroless Ni-W-P plating, porosity formation and grain growth and microstrain/residual stress resulting from laser-induced nanocrystallization are the major concerns, affecting corrosion performance. In addition, potential applications of LSM as pre-treatment method prior to conventional anodizing or post-treatment of thermal sprayed coatings have been demonstrated.

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6

Zhang, Xiao Feng, and Lutgard C. De Jonghe. "Thermal Modification of Microstructures and Grain Boundaries in Silicon Carbide." Journal of Materials Research 18, no. 12 (December 2003): 2807–13. http://dx.doi.org/10.1557/jmr.2003.0391.

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Polycrystalline SiC samples hot pressed with aluminum, boron, and carbon sintering additions (ABC-SiC) were characterized using transmission electron microscopy. The study focused on the effects of high-temperature treatment on microstructure. Three temperatures, at which considerable microstructural changes took place, were found to be critical. At a threshold temperature of approximately 1000°C, 1-nm-wide, amorphous intergranular films started to crystallize. At approximately 1300°C, lattice diffusion in SiC grains resulted in nanoprecipits, which could diffuse into grain boundaries and significantly altered composition. Quantitative microanalysis revealed doubled Al content in intergranular films after annealing at 1300°C. Except for crystallization in intergranular films and nano-precipitation in matrix grains, microstructure remained stable until 1600°C, when microstructural changes with volatile features occurred. A brief holding at 1900°C brought marked changes in microstructure, including structural change in intergranular films, dissolved nanoprecipitates, unit cell dilation, and cracking. The results indicate that ABC-SiC is highly promising in structural applications at up to 1500°C.

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7

Liang, Yu, Hao Ding, Sijia Sun, and Ying Chen. "Microstructural Modification and Characterization of Sericite." Materials 10, no. 10 (October 16, 2017): 1182. http://dx.doi.org/10.3390/ma10101182.

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8

Patra, Srabani, Janani Narayanasamy, Thamayanthi Panneerselvam, and Ramaswamy Murugan. "Review—Microstructural Modification in Lithium Garnet Solid-State Electrolytes: Emerging Trends." Journal of The Electrochemical Society 169, no. 3 (March 1, 2022): 030548. http://dx.doi.org/10.1149/1945-7111/ac5c99.

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Garnet structured solid electrolytes-based lithium metal batteries are the most attractive high energy density electrochemical energy storage candidates for the transportation and grid sectors. Various studies are carried out to address the concerns of lithium garnets as solid electrolytes and improve their electrochemical performance in lithium metal batteries. Interfacial engineering is a widely studied strategy for improving lithium garnet electrolyte-electrode interfacial contact and critical current densities. In the same perspective, microstructural/grain boundary engineering in lithium garnet is an effective strategy for overcoming obstacles and increasing critical current densities (CCD) in lithium metal battery research. The importance of the microstructural properties of the solid electrolyte has been discussed in several investigations. However, a comprehensive overview of the microstructural modification of lithium garnet solid electrolytes and their effect on electrochemical performance is still lacking. This review presents a detailed discussion on the strategies used to modify the microstructure and their impact on performances such as ionic conductivity, interfacial contact, critical current density, dendrite kinetics, etc., of lithium garnet ceramics.

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9

Florea, Costel, Costică Bejinariu, Ioan Carcea, Viorel Paleu, Daniela Chicet, and Nicanor Cimpoeşu. "Preliminary Results on Microstructural, Chemical and Wear Analyze of New Cast Iron with Chromium Addition." Key Engineering Materials 660 (August 2015): 97–102. http://dx.doi.org/10.4028/www.scientific.net/kem.660.97.

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A new cast-iron material was obtained by melting in an induction furnace. The material was microstructural and chemical characterized before and after a wear test. We analyze the chemical composition of the material at macro-scale using a Spark Spectrometer and at micro-scale using Dispersive Energy Spectrometer. Microstructure before and after the external solicitations was observed using a Scanning Electron Microscope. We also evaluate the influence of external force on the dendrites microstructural and chemical modification.

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10

Snopiński, Przemysław. "Effect of Al10Sr and TiB on the Microstructure and Solidification Behavior of AlMg5Si2Mn Alloy." Solid State Phenomena 326 (November 2, 2021): 111–24. http://dx.doi.org/10.4028/www.scientific.net/ssp.326.111.

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In the first stage of the experiment, the effect of Al10Sr modification and Al5TiB grain refiner and interaction of both additions on the microstructure of AlMg5Si2Mn alloy and Mg2Si phase morphology was investigated. Then the influence of Al10Sr and Al5TiB addition on nucleation temperatures of various intermetallic phases formed in AlMg5Si2Mn alloy also have been interpreted by the formation of distinct peaks in the first derivative cooling curve and microstructural observations. It was found that modification has a meaningful influence on the microstructure of the investigated alloy as well as the crystallization process

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11

Bousquet, Emilie, Angéline Poulon-Quintin, Olivier Devos, Monique Puiggali, and Marie Touzet. "Microstructure, Mechanical and Corrosion Behaviour of AN AA2024-T3 FSW Joint." Advanced Materials Research 409 (November 2011): 257–62. http://dx.doi.org/10.4028/www.scientific.net/amr.409.257.

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The FSW weld consists of three distinct microstructural zones. The microstructure inside each zone is directly impacted by the FSW process parameters. The aim of this article is to correlate microstructure, microhardness and corrosion sensitivity of a AA-2024-T3 FSW joint for one processing parameter set. A microstructural analysis has been conducted in each weld zone by the combination of TEM observations, chemical and DSC analysis. Moreover, a small electrochemical cell was used to estimate the corrosion sensitivity of the distinct zones by localized open circuit potential measurements all along the weld. Mechanical properties were evaluated using Vickers microhardness measurements. The results show a direct correlation between mechanical property evolution, local corrosion process involved and microstructure modification.

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12

Iwase, Akihiro, and Fuminobu Hori. "Modification of Lattice Structures and Mechanical Properties of Metallic Materials by Energetic Ion Irradiation and Subsequent Thermal Treatments." Quantum Beam Science 4, no. 1 (March 16, 2020): 17. http://dx.doi.org/10.3390/qubs4010017.

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When materials are irradiated with high-energy ions, their energies are transferred to electrons and atoms in materials, and the lattice structures of the materials are largely changed to metastable or non-thermal equilibrium states, causing the modification of several physical properties. There are two processes for the material modification by ion irradiation; one is “the irradiation-enhanced process”, and the other is “the irradiation-induced process”. In this review, two kinds of recent results for the microstructural changes and the modifications of mechanical properties will be summarized: one is the hardness modification of dilute aluminum alloys, which is a result of the irradiation-enhanced process, and the other is the hardness modification of Ni-based intermetallic compounds as a result of the irradiation-induced process. The effect of the subsequent thermal treatment on the microstructures and the hardness for ion-irradiated dilute aluminum alloys is quite different from that for Ni-based intermetallic compounds. This result reflects the difference between the irradiation-enhanced process and the irradiation-induced process. Finally, possibilities of the ion irradiation and subsequent thermal treatment to industrial applications will also be discussed.

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13

Li, Kejian, Qiang Zheng, Chunhong Li, Bin Shao, Donglin Guo, Dengming Chen, Jianchun Sun, Jiling Dong, Pengjun Cao, and Keesam Shin. "Characterization of Surface Modification of 347 Stainless Steel upon Shot Peening." Scanning 2017 (2017): 1–4. http://dx.doi.org/10.1155/2017/2189614.

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Plastic deformations, such as those obtained by shot peening on specimen surface, are an efficient way to improve the mechanical behavior of metals. Generally, scanning electron microscopy (SEM) and electron backscattered diffraction (EBSD) are commonly used to observe the complex microstructural evolutions, such as grain refinement and phase transformation, induced by the surface treatment. In this work, the microstructure of 347 stainless steel, after ultrasonic shot peening (USP) treatments, was investigated. SEM, EBSD, transmission electron microscopy, and X-ray diffraction were used to observe the microstructural evolutions, such as grain refinement and phase transformation. Deformation depth after the USP treatment was about 200 μm. Grain size on the treated surface layer was about 100 nm, with two phases: austenite and α′-martensite. The percentages of the austenite and α′-martensite phases were 54% and 46%, respectively, which constitute an exact expression of the degree of plastic deformation on austenitic stainless steel.

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14

Gariboldi, Elisabetta, and Marco Colombo. "Characterization of Innovative Al-Si-Mg-Based Alloys for High Temperature Applications." Key Engineering Materials 710 (September 2016): 53–58. http://dx.doi.org/10.4028/www.scientific.net/kem.710.53.

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The role played by transition elements and rare earths, added in small quantities (fractions of unity in weight percent) was proved by several authors to be beneficial for the age-hardening response and for the microstructural stability at high temperature of Al-based alloys. The paper illustrates the results of an experimental investigation on the effects of erbium (Er) additions on the microstructural features, microstructural stability and mechanical properties of an Al-7Si-0.4Mg alloy of wide industrial use. The effects are multifold: in the cast microstructure, a silicon (Si) eutectic modification was observed with the formation of several Er-containing intermetallic phases. After solution treatment and aging, an increase in peak hardness and an enhanced microstructural stability were obtained. In this preliminary study, the beneficial effects of Er additions were confirmed.

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15

Iqbal, Muhammad, J. I. Akhter, A. Qayyum, Y. Javed, M. Rafiq, and A. A. Khuram. "Surface Modification and Characterization of Bulk Amorphous Materials." Key Engineering Materials 510-511 (May 2012): 43–50. http://dx.doi.org/10.4028/www.scientific.net/kem.510-511.43.

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Bulk metallic glasses (BMGs) are well known for their promising properties. Surface properties can be further improved by using certain techniques such as electron beam melting (EBM), laser beam melting (LBM), ion irradiation, ion implantation and neutron irradiation. BMGs especially Zr-based BMGs have numerous applications as structural materials. In this manuscript, the results are presented on microstructural investigations and phase formations in Zr-based BMGs modified by using above mentioned techniques. Microstructure was studied by scanning electron microscopy (SEM). Phase analysis was done by X-ray diffraction (XRD) and confirmed by energy dispersive spectroscopy (EDS). Vickers hardness was measured and correlated with the microstructure. The phases identified in Zr-Cu-Al-Ni alloy samples modified by EBM, LBM and ion irradiation are Ni-Zr, NiZr2, CuZr2, Cu10Zr7 and Al2NiZr6. ZrSi2 phase was detected in Zr55Cu30Al10Ni5 and Zr65Cu17Ni10Al8 BMGs irradiated with Si+ (ions). About 20-35 % increase in hardness and elastic moduli was achieved by surface modification. Modifications of BMGs by electron and laser beams melted the materials surfaces while ion irradiation improved the mechanical properties of localized zones without melting.

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16

Ohtaki, Michitaka, Daisuke Ogura, Koichi Eguchi, and Hiromichi Arai. "Thermoelectric Properties of Sintered FeSi2with Microstructural Modification." Chemistry Letters 22, no. 6 (June 1993): 1067–70. http://dx.doi.org/10.1246/cl.1993.1067.

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17

Costa e Silva, A., and M. J. Kaufman. "Microstructural modification of MoSi2 through aluminum additions." Scripta Metallurgica et Materialia 29, no. 8 (October 1993): 1141–45. http://dx.doi.org/10.1016/0956-716x(93)90192-u.

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18

Kumar, K. G. Basava. "Influence of Refinement and Modification on Dry Sliding Wear Behavior of Hypereutectic Al-Si Cast Alloys." Advanced Materials Research 685 (April 2013): 112–16. http://dx.doi.org/10.4028/www.scientific.net/amr.685.112.

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The microstructures and dry sliding wear behavior of Al-17Si cast alloys were studied after various melt treatments such as refinement and modification. Results indicate that combined refined and modified Al-17Si cast alloys have microstructures consisting of uniformly distributed primary silicon and fine eutectic AlSilicon particles through out the matrix. These alloys exhibited better wear resistance in the cast condition compared with the same alloy subjected to only refinement or modification. The improvements in properties observed in the present studies are mainly due to the structural differences between the refined, modified or both refined and modified over just cast Al-Si alloys. This paper attempts to investigate the influence of the microstructural changes in the Al-17Si cast alloys by refinement, modification and combined action of both on the dry sliding wear behavior.

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19

Wusatowska-Sarnek, Agnieszka M., Gautam Ghosh, Gregory B. Olson, Martin J. Blackburn, and Mark Aindow. "Characterization of the microstructure and phase equilibria calculations for the powder metallurgy superalloy IN100." Journal of Materials Research 18, no. 11 (November 2003): 2653–63. http://dx.doi.org/10.1557/jmr.2003.0371.

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The microstructure of the Ni-based superalloy IN100 processed by a powder metallurgy route was evaluated to reveal the structures, volume fractions, distributions, and chemistries of the various phases present. These data were compared with those predicted by computational thermodynamics. It is shown that the microstructural parameters expected on the basis of global equilibrium conditions differ significantly from those measured experimentally. However, modification of these calculations by use of constrained and successive equilibria compensated for kinetic effects and led to accurate (or better) predictions of phase volume fractions and chemistries in this alloy. This demonstrated that such modified phase equilibria calculations could be powerful tools for modeling microstructures, even in complex multicomponent alloys processed under nonequilibrium conditions.

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20

Tantiwaitayaphan, Tanawat, Phromphong Pandee, and Chaowalit Limmaneevichitr. "Modification of Eutectic Si in Hypoeutectic Al-Si Alloys with Erbium Addition." Key Engineering Materials 718 (November 2016): 139–42. http://dx.doi.org/10.4028/www.scientific.net/kem.718.139.

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Effect of erbium (Er) on the eutectic Si morphologies in hypoeutectic Al-Si based alloys was investigated using thermal analysis and microstructure examination. The microstructural observations show that the addition of Er causes significant modification of the eutectic silicon morphology from a coarse plate-like to a fine fibrous one. Furthermore, the results of thermal analysis reveal that the addition of Er decreased the temperatures of eutectic nucleation and growth, and increased the eutectic undercooling. The eutectic undercooling caused by the presence of Er plays an important role in the modification of eutectic silicon.

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21

Li, Pengfei, Wenhao Gan, Guoyou Yao, Qiao Huang, and Renming Zhao. "Effect of Permeable Crystalline Materials on the Mechanical and Porosity Property of Recycled Aggregate and Recycled Aggregate Concrete." Materials 16, no. 13 (June 26, 2023): 4596. http://dx.doi.org/10.3390/ma16134596.

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This study investigates the potential of permeable crystalline materials to improve the properties of recycled aggregates and recycled aggregate concrete (RAC). The use of recycled aggregates in concrete production has gained increasing attention due to environmental and economic benefits. However, the lower quality and poorer durability of recycled aggregates limit their wider application. In this study, three types of recycled aggregates were treated with permeable crystalline materials, and their water absorption and crushing index were compared before and after modification. RAC was then produced using modified recycled aggregates with different substitution rates, and their mechanical properties were evaluated. To investigate the mechanism of permeable crystalline materials modification, the microstructure of the modified RAC was observed using nuclear magnetic resonance and scanning electron microscopy. The results demonstrated that the permeable crystalline materials treatment effectively reduced the water absorption and crushing index of the recycled aggregates. The compressive strength of modified RAC also improved, with a higher modification time leading to higher strength. Furthermore, the pore distribution and microstructural denseness of the modified recycled aggregates and RAC were enhanced, as revealed by the microstructural observations. These findings suggest that permeable crystalline materials modification is a promising method for improving the properties of recycled aggregates and RAC, which could contribute to the sustainable development of the construction industry.

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22

Lathabai, Sri, R. Migeon, V. K. Tyagi, Robert G. O'Donnell, and Yuri Estrin. "Friction Stir Processing: A Technique for Microstructural Refinement in Metallic Materials." Materials Science Forum 618-619 (April 2009): 63–67. http://dx.doi.org/10.4028/www.scientific.net/msf.618-619.63.

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Friction stir processing (FSP) combines frictional heating and severe plastic deformation to produce microstructural modification, either locally targeted at the near-surface regions or through the bulk, of metallic components fabricated by conventional processing routes. In this paper, we highlight the capabilities of this process by applying it to a high-pressure die cast Al-Si-Mg-(Cu) alloy and examining the resulting microstructure and mechanical properties.

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23

Rodrigues, Adilson Vitor, Rafael Kakitani, Cássio Silva, Leonardo Giovanetti, Marcelino Dias, Hani Henein, Amauri Garcia, and Noé Cheung. "Influence of Minor Additions of Be on the Eutectic Modification of an Al-33wt.%Cu Alloy Solidified under Transient Conditions." Metals 13, no. 1 (January 2, 2023): 94. http://dx.doi.org/10.3390/met13010094.

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Al-based alloys are often selected for use in various engineering applications as well as in the aircraft and aerospace industry. The improvement of their performances under severe conditions have required the use of alloying elements. In the present work, Be is added to the eutectic Al-33 wt.%Cu alloy with a view to investigating the resulting effects on microstructural features and hardness. A directional solidification technique is used, yielding a wide range of solidification cooling rates. This permits microstructural features to be investigated with emphasis on the role of Be on the eutectic morphology. The directionally solidified microstructures are formed by eutectic colonies for the Al-33 wt.%Cu alloy, however, with additions of both 0.05 and 0.5 wt.% Be, the original cell-like morphology is transformed into a trefoil-like morphology. This together with the α-Al dendritic pattern characterize the microstructure of the Al-33Cu-Be alloys examined. Solidification growth laws are experimentally derived relating dendritic and eutectic colony spacings to solidification cooling rates and growth rates. The length scale of such spacings is shown not to affect the Vickers hardness of the Al-33Cu-Be alloys examined; however, the additions of Be are shown to improve the brittle behavior of the Al-33 wt.%Cu alloy.

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Fracchia, Elisa, Federico Simone Gobber, and Mario Rosso. "Effect of Alloying Elements on the Sr Modification of Al-Si Cast Alloys." Metals 11, no. 2 (February 19, 2021): 342. http://dx.doi.org/10.3390/met11020342.

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Strontium-based modifier alloys are commonly adopted to modify the eutectic silicon in aluminum-silicon casting alloys by changing the silicon shape from an acicular to a spherical form. Usually, the modifier alloy necessary to properly change the silicon shape depends on the silicon content, but the alloying elements’ content may have an influence. The AlSr10 master alloy’s modifying effect was studied on four Al-Si alloys through the characterization of microstructural and mechanical properties (micro-hardness and impact tests). The experimental results obtained on gravity cast samples highlighted the interdependence in the modification of silicon between the Si content and the alloying elements. After modification, a higher microstructural homogeneity characterized by a reduction of up to 22.8% in the size of intermetallics was observed, with a generalized reduction in secondary dendritic arm spacing. The presence of iron-based polygonal-shaped intermetallics negatively affects Sr modification; coarser silicon particles tend to grow close to α-Fe. The presence of casting defects such as bifilm reduces Sr modification’s beneficial effects, and little increase in absorbed impact energy is observed in this work.

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25

Shastin, V. I., and S. K. Kargapol’tsev. "Laser Modification: Increasing the Wear Resistance of Friction Surfaces." Key Engineering Materials 836 (March 2020): 104–10. http://dx.doi.org/10.4028/www.scientific.net/kem.836.104.

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The article deals with topical issues of studying the physical, mechanical and tribological parameters of the surface layer of machine parts subjected to laser processing. Various options for modifying mating surfaces are evaluated and analyzed. The data of microstructural analysis and indicators of wear resistance are presented. A theoretical model of the wear of heat-strengthened surfaces is proposed, explaining the mechanism for increasing their wear resistance as a result of homogenization of the microstructure of a special surface layer with increased bearing capacity. It is experimentally confirmed that the greatest wear resistance is observed in friction units during mutual modification of mating surfaces.

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26

Kusinski, G. J., and G. Thomas. "Physical and Magnetic Modification of Co/Pt Multilayers by Ion Irradiation." Microscopy and Microanalysis 8, no. 4 (August 2002): 319–32. http://dx.doi.org/10.1017/s1431927602020275.

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The microstructure of Co/Pt multilayers with large perpendicular magnetic anisotropy (PMA) was investigated before and after energetic ion irradiation. No pronounced microstructural changes were detected at ion doses sufficient to completely reduce the PMA and cause a spin reorientation transition to in-plane. Ion-induced displacement of Co and Pt atoms near Co/Pt interfaces lead to local “roughening” and Co layer strain relaxation, reducing the PMA. The magnetic domain confinement induced by ion irradiation and magnetic patterning by selective ion irradiation were also investigated.

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27

Schmidt, Christopher David, Hans-Jürgen Christ, and Axel Von Hehl. "Hydrogen as a Temporary Alloying Element for Establishing Specific Microstructural Gradients in Ti-6Al-4V." Metals 12, no. 8 (July 28, 2022): 1267. http://dx.doi.org/10.3390/met12081267.

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Parts of vehicles, such as landing gear components of aircrafts, are subject to growing demands in terms of sustainability via lightweight design and durability. To fulfill these requirements, the development of thermochemical processes is auspicious. Titanium alloys allow a heat treatment in hydrogen-containing atmosphere for temporary hydrogen alloying, often called thermohydrogen treatment (THT). The investigation presented intends to realize a local microstructure modification of Ti-6Al-4V by means of THT. The study aims to use hydrogen (H) as a promoter for changing the local distribution and morphology of strengthening precipitates during THT as well as the local grain size (microstructural gradient). Both shall improve the fatigue properties of the material after hydrogen degassing. To derive suitable thermohydrogen treatment process parameters, the resulting fatigue crack propagation resistance and fracture toughness after different solution heat treatments are determined experimentally and compared to each other. Moreover, various graded microstructures are evaluated after hydrogen uptake (hydrogenation) and hydrogen degassing (dehydrogenation) using numerically simulated hydrogen concentration profiles, observed hardness curves, metallographically determined microstructure gradients and the corresponding results of the phase analysis by means of X-ray diffraction. The study shows that hydrogenation at 500 °C and dehydrogenation at 750 °C enables the generation of a promising microstructural gradient.

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28

Venkateswarlu, G., M. J. Davidson, G. R. N. Tagore, and P. Sammaiah. "Influence of Process Parameters on Microstructure of Friction Stir Processed Mg AZ31 Alloy." International Journal of Surface Engineering and Interdisciplinary Materials Science 2, no. 1 (January 2014): 47–58. http://dx.doi.org/10.4018/ijseims.2014010103.

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Friction stir processing (FSP) has been developed on the principles of friction stir welding (FSW) as an effective and efficien new method for grain refinement and microstructural modification, providing intense plastic deformation as well as higher strain rates than other conventional severe plastic deformation methods. FSP produces an equiaxed homogeneous microstructure consisting of fine grains, resulting in the enhancement of the properties of the material at room temperature. The objective of the present paper is to examine the influence of friction stir processing (FSP) parameters namely tool rotational speed (RS), tool traverse speed (TS) and tool tilt angle (TA) on the microstructures of friction stir processed AZ31B-O magnesium alloy. This investigation has focused on the microstructural changes occurred in the dynamically recrystallised nugget zone/ stir zone and the thermo mechanically affected zone during FSP. The results presented in this work indicate that all the three FSP process parameters have a significant effect on the resulting microstructure and also found that the rotational speed has greatly influenced the homogenization of the material. The grain refinement is higher at intermediate rotational speed (1150 rpm), traverse speed (32 mm / min and tilt angle (10). It is established that FSP can be a good grain refinement method for improving the properties of the material.

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29

Widener, Christian A., Dwight A. Burford, and Sarah Jurak. "Effects of Tool Design and Friction Stir Welding Parameters on Weld Morphology in Aluminum Alloys." Materials Science Forum 638-642 (January 2010): 1261–66. http://dx.doi.org/10.4028/www.scientific.net/msf.638-642.1261.

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Friction stir welding (FSW) is a complex thermo-mechanical process which produces wrought microstructure with microstructural gradients in grain size, grain orientation, dislocation density, and precipitate distribution. The type and degree of microstructural modification is a function of the particular alloy chosen, its initial temper, the tool design and corresponding weld process parameter window, and other variables like material thickness, size, fixturing, etc. Since the microstructural changes produced can dramatically affect resultant mechanical performance and corrosion response, a thorough understanding of the variables involved in those changes is needed. A design of experiments approach was used to study the effects of welding parameter selection on the microstructural changes wrought by FSW with two different sizes of the same FSW tool design. A combination of microhardness mapping and electrical conductivity testing was used to investigate potential differences. The importance of these factors and the means for characterizing them for developing standards and specifications are also discussed.

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30

Nakagawa, Shohei, Angga Afrinaldi, Toshifumi Kakiuchi, Yoshihiko Uematsu, Akio Ohtani, Kazuhiro Kumabe, and Yoshiki Mizutani. "Microstructural Modification of AZ91 Magnesium Alloy Using Friction Stir Processing and Carbon Fibers." Materials Science Forum 886 (March 2017): 55–58. http://dx.doi.org/10.4028/www.scientific.net/msf.886.55.

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The microstructure of cast magnesium (Mg) alloy, AZ91, was modified by a friction stir process (FSP) technique. FSP was applied to AZ91 plate with a narrow slit, in which carbon fibers (CFs) were filled. The rotating FSP tool consisting of probe and shoulder could modify the microstructure of the material by sever plastic deformation (SPD) and simultaneously disperse CFs into the matrix. Microstructural observation revealed that sever stirring of material by a tool resulted in the grain refinement due to the dynamic recrystallization and distribution of CFs into the stir zone (SZ). The distribution was not uniform depending on the plastic flow in the SZ, but any worm-hole defects were not formed. Hardness of FSPed AZ91 in the SZ was higher than the as-casted AZ91 because of the grain refinement and distribution of hard CFs.

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31

Christides, C., S. Stavroyiannis, N. Boukos, A. Travlos, and D. Niarchos. "Microstructural modification in Co/Cu giant-magnetoresistance multilayers." Journal of Applied Physics 83, no. 7 (April 1998): 3724–30. http://dx.doi.org/10.1063/1.366598.

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32

Dong, Guoping, Liaolin Zhang, Mingying Peng, Jianrong Qiu, Geng Lin, Fangfang Luo, Bin Qian, and Quanzhong Zhao. "Microstructural modification of chalcogenide glasses by femtosecond laser." Journal of Non-Crystalline Solids 357, no. 11-13 (June 2011): 2392–95. http://dx.doi.org/10.1016/j.jnoncrysol.2010.11.074.

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33

Noell, Philip J., Jeffrey M. Rodelas, Zahra N. Ghanbari, and Chris M. Laursen. "Microstructural modification of additively manufactured metals by electropulsing." Additive Manufacturing 33 (May 2020): 101128. http://dx.doi.org/10.1016/j.addma.2020.101128.

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34

Huang, Her-Yueh, Iang-Chuen Kuo, and Chia-Wei Zhang. "Friction-stir welding of aluminum alloy with an iron-based metal as reinforcing material." Science and Engineering of Composite Materials 25, no. 1 (January 26, 2018): 123–31. http://dx.doi.org/10.1515/secm-2016-0065.

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AbstractThe fabrication of a durable and usable aluminum matrix composite poses a challenge because it is hard to obtain defect-free welds by using conventional fusion welding methods. The development of friction-stir welding (FSW) provides improved microstructure modification. As there are no melting problems associated with it, liquid-solid reactions are eliminated. The objective of this study was to attempt FSW of an AA6061 alloy reinforced with an iron-based metal and to determine the properties of the joints. The effects of FSW parameters, especially the tool rotation speed, are presented first. Then, the application of the technique in manufacturing and microstructure modification of particle-reinforced composite materials is discussed. Finally, interfacial microstructural changes and the associated mechanical properties are evaluated.

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35

Zulkfli, Zuhairah, Zamzuri Hamedon, and Nanang Fatchurrohman. "Surface Modification on Magnesium Alloys’ Hardness and Microstructure Using Friction Stir Processing – A Review." Jurnal Teknologi 13, no. 1 (June 29, 2023): 39–45. http://dx.doi.org/10.35134/jitekin.v13i1.91.

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Low density of magnesium-based alloy is one potential as the lightest structural material for light weight-high strength applications for automotive and aerospace. Severe plastic deformation (SPD) together with thermomechanical processing are proved to be a successful method for attaining desired microstructural modifications through achieving fine and highly misoriented microstructures and creating various structures to the bulk properties of magnesium alloy. The material's deformation can result in an altered microstructure that is gainful to the material's requirements. However, the poor deformability of magnesium and its alloys limits the application of the thermomechanical approach. Controlling over temperature and deformation rate is hard to achieve. Among the thermomechanical processes, friction stir processing (FSP) offers an easy way to achieve process stability and mechanical properties enhancement by heat treatment which results in the closure of porosity and refined grain size. During this process, heat is generated by the rotation of the FSP processing tool. Few process parameters such as rotational and traverse speeds should be controlled to make FSP stay within the defined processing condition. It is critical to set the right tool rotational speed as well as traverse speed to ensure adequate heat generation. As there are no established standards for operating the FSP, the only solution is to experiment with different settings to find the best parameter which will produce better quality on processed magnesium alloy workpiece. This paper explores earlier studies on surface modification via FSP technique to improve the mechanical properties strengthening of magnesium alloy mainly on grain size and hardness. The surface modification was done mostly on popular series of magnesium alloy (AZ series) using different tool material, tool geometry and different parameters combination. A comprehensive view of surface modification on magnesium alloys which includes the FSP tool and workpiece material used, variations of FSP parameters settings as well as the effect on hardness and microstructure analysis will be discussed.

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36

Jackson, Ben, Rob Torrens, Leandro Bolzoni, Fei Yang, Mike Fry, and Aamir Mukhtar. "Additive Manufacturing of Ti-6Al-4V with Added Boron: Microstructure and Hardness Modification." Key Engineering Materials 770 (May 2018): 165–73. http://dx.doi.org/10.4028/www.scientific.net/kem.770.165.

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Titanium alloy composites with titanium boride (TiB) discontinuous reinforcement have shown improved performance in terms of strength, stiffness, and hardness. Producing this composite through selective laser melting (SLM) can combine the advantages of freeform design with the ability to produce TiB reinforcement in-situ. In this study, SLM was used to consolidate a pre-alloyed Ti-6Al-4V (Ti64) and amorphous boron (B) powder mixture with the intent of producing 1.5wt% TiB reinforcement in a Ti64 matrix. The processing parameters of laser power and scanning speed were investigated for their effect on the density, microstructures, and hardness of the composite material. The results showed that the boron and Ti64 composite could achieve a density greater than 99.4%. Furthermore, it was found that processing parameters changed the microstructural features of the material. The higher the energy density employed the more homogenous the distribution of boron modified material. Macro features were also observed with laser paths being clearly evident in the subsurface microstructure. Micro-hardness testing and density measurement also showed a corresponding increase with increasing energy density. Maximum hardness of 392.4HV was achieved in the composite compared to 354.2HV in SLM fabricated Ti64.

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37

Ahmed, Hadj sadok. "Effect of the microstructure of mortars with low hydraulicity slag on their behavior in aggressive environments." MATEC Web of Conferences 149 (2018): 01025. http://dx.doi.org/10.1051/matecconf/201814901025.

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Slag is one of the most used cement additives. Due to its latent hydraulic nature, attached to its hydraulicity, it can contribute to a microstructural modification and an improvement of the durability of the concrete face of aggressive environments. In this study, a low active slag is used in the manufacture of mortars as a substitute for cement, at a maximum rate of 50%. Firstly, a study of the microstructure with mercury porosimetry was used for determination of microstructural parameters (porosity, diameters and volume distribution). The behavior of mortars in aggressive environments (sodium and magnesium sulphate and seawater) was studied later. Despite the low reactivity of studied slag, its presence especially at 50% rate, in the long term, has led to a refinement of the microstructure. This effect, among others, led to better resistivity of the mortars in the sulphate environnements.

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38

Nenadovic, S., M. Nenadovic, R. Kovacevic, Lj Matovic, B. Matovic, Z. Jovanovic, and J. Novakovic-Grbovic. "Influence of diatomite microstructure on its adsorption capacity for Pb(II)." Science of Sintering 41, no. 3 (2009): 309–17. http://dx.doi.org/10.2298/sos0903309n.

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The effect of microstructural changes caused by mechanical modification on adsorption properties of diatomite samples were investigated. The microstructure has been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM) while the degree of metal adsorption was evaluated by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP AES). The results show that metal sorption capacity of diatomite is considerably improved after mechanical modification and it can be attributed to amorphysation of the material. Immobilization efficiency increased from 22% for untreated to 81% for the treated sample after 5h at BPR 4.This qualifies natural diatomite as a material for wastewater remediation.

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39

Bazhenova, B. A., A. A. Tykheev, Ts Yumzhir-Uvdel, Yu Yu Zabalueva, T. S. Bychkova, and L. V. Danilova. "Modification of collagen-containing animal raw materials for use in food products." IOP Conference Series: Earth and Environmental Science 1052, no. 1 (July 1, 2022): 012032. http://dx.doi.org/10.1088/1755-1315/1052/1/012032.

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Abstract The article analyzes the microstructure of collagen of animal raw materials, modified by a chemical method by exposing the tripe tissue in dry sodium bicarbonate and subsequent exposure in a solution of acetic acid to improve its technological characteristics. The objects of research were beef tripe tissue from a freshly slaughtered animal before (control) and after modification (experiment). The modification was carried out in accordance with the following scheme: sequential exposure of the tripe tissue for 60 min with sodium bicarbonate in dry form, distributed over the surface of the tripe tissue, at a ratio of 10: 1, then rinsing in running cool water, then subsequent exposure in 2% food grade acetic acid for 30 minutes. In the course of the experiment, the following studies were carried out: microstructural analysis, changes in the indicators of cutting force and the content of amine nitrogen. The obtained experimental data showed that the treatment causes a change in the collagen microstructure of the tripe tissue: there is a widespread loosening of the cicatrix wall and destructive changes in collagen and muscle fibers, swelling and loosening the muscle fibers, while the striation of the fiber structure is significantly changed. In individual muscle bundles, elongated nuclei are noticeable, which are located eccentrically; in some areas of the stratified epithelium, cell nuclei were absent. Microstructural and biochemical analysis proves the presence of morphological and structural processes in the tripe tissue after the proposed method of chemical treatment, which improves its characteristics for further technological processing and the addition of sausages.

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40

Sun, Ning, and Diran Apelian. "Microstructural Modification of A206 Aluminium via Friction Stir Processing." Materials Science Forum 618-619 (April 2009): 361–64. http://dx.doi.org/10.4028/www.scientific.net/msf.618-619.361.

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Friction stir processing (FSP) is a post-processing method that locally manipulates microstructure by imparting a high level of energy in the solid state giving rise to improved mechanical properties. FSP was applied to 25.4 mm thick, sand casting A206 aluminum workpiece under different parameters. Effects of FSP on microstructure evolution will be described and discussed. Specifically, through optical microscopy and SEM measurements the attained refinement in the stirred zone will be reviewed; porosity is significantly reduced and second phase particles are fragmented. Thermal conditions of the FSP zone have been measured as well as studying the effect of the temperature gradients on the resultant structure.

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41

Hossain, Rumana, Farshid Pahlevani, and Veena Sahajwalla. "Surface modification of high carbon steel through microstructural engineering." Materials Characterization 148 (February 2019): 116–22. http://dx.doi.org/10.1016/j.matchar.2018.12.020.

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42

Santo, Loredana, Denise Bellisario, Ludovica Rovatti, and Fabrizio Quadrini. "Microstructural Modification of Laser-Bent Open-Cell Aluminum Foams." Key Engineering Materials 504-506 (February 2012): 1213–18. http://dx.doi.org/10.4028/www.scientific.net/kem.504-506.1213.

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Laser forming tests have been performed on open-cell aluminum alloy foams with different pore size. Laser power was fixed at 150 W, a total of 150 laser scans led to a bending angle up to 60°, depending on the laser scan rate. At the end of the laser bending, the foams were left to cool and samples were extracted for analysis by means of an optic microscope. The alloy microstructure was investigated in different points of the samples and correlated with the processing conditions. Image analysis was also carried out to extract the percentage of melted area due to laser heating.

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43

Rao, R. V. Subba, P. Parameswaran, and R. K. Dayal. "Microstructural Modification in a Laser-Treated 2.25Cr-1Mo Steel." Journal of Materials Engineering and Performance 10, no. 5 (October 1, 2001): 515–20. http://dx.doi.org/10.1361/105994901770344647.

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44

Was, Gary S. "Ion beam modification of metals: Compositional and microstructural changes." Progress in Surface Science 32, no. 3-4 (January 1989): 211–332. http://dx.doi.org/10.1016/0079-6816(89)90005-1.

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45

Chen, Zubin, Xiaoguo Song, and Yun Luo. "Ion bombardment induced surface microstructural modification of aluminum alloy." Vacuum 215 (September 2023): 112266. http://dx.doi.org/10.1016/j.vacuum.2023.112266.

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46

Tosangthum, Nattaya, Monnapas Morakotjinda, Rungtip Krataitong, Pongsak Wila, Thanyaporn Yodkaew, and Ruangdaj Tongsri. "Modification of Microstructure and Tensile Property of Sintered Fe-Cr-Mo-C Steel by Nickel Addition." Key Engineering Materials 751 (August 2017): 42–46. http://dx.doi.org/10.4028/www.scientific.net/kem.751.42.

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Nickel is one of the alloying elements promoting the formation of acicular ferrite at the expense of proeutectoid ferrite. The Ni addition reduces the steady-state nucleation rates of grain boundary ferrite allotriomorph in Fe-C-Ni alloys. Due to such reasons, Ni was added to modify the microstructure of the sintered steel, investigated in this study, with the aim of improved mechanical properties. The sintered steel, produced from pre-alloyed Fe-Cr-Mo powder mixed with 0.3 wt.% C, was modified by Ni addition and cooling rate. The alloy compositional change was performed additions of varied Ni contents of 1.0, 1.5, 2.0, 2.5 and 3.0 wt.%. The material processing variables were investigated by using two different cooling rates of 0.1 and 5.4 °Cs-1. Under the cooling rate of 0.1 °Cs-1, the sintered Fe-Cr-Mo-3C steel without Ni addition showed dual-phase microstructure consisting of ferrite (soft phase) and bainite (hard structure). With Ni additions, the dual-phase microstructure was replaced by bainitic structure. Microstructural heterogeneity was observed due to the presence of Ni-rich areas, which increased with increasing added Ni contents. Under the cooling rate of 5.4 °Cs-1, the sintered Fe-Cr-Mo-3C steels with and without Ni additions showed bainitic structure. Microstructural heterogeneity was similar to that of slowly cooled steel. Ni additions not only modified the sintered steel microstructure but increased tensile strength and elongation. In general, Ni pushes the C-curve of pearlite transformation to the right hand side and lowers the martensite start temperature. The absence of ferrite from the sintered steel with only 1 wt.% Ni addition and slowly cooled at 0.1 °Cs-1 suggests that Ni strongly suppresses the austenite → ferrite transformation. In another word, Ni promotes bainite formation in the sintered Fe-Cr-Mo-Ni-C steels.

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47

John, Merbin, Udaya Bhat Kuruveri, and Pradeep L. Menezes. "Laser Cladding-Based Surface Modification of Carbon Steel and High-Alloy Steel for Extreme Condition Applications." Coatings 12, no. 10 (September 30, 2022): 1444. http://dx.doi.org/10.3390/coatings12101444.

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Laser cladding (LC) is a laser-based surface modification technique widely adopted to develop a thin coating or remanufacture worn-out mechanical components that work in extreme conditions. LC helps to generate superior surface properties and surface integrity on the substrate surface, improving the service life. This review paper provides a comprehensive overview of the LC process, different powder feeding methods, and the uniqueness of LC over other coating techniques. More specifically, the current state-of-the-art of the LC process on carbon steel and high-alloy steel-based mechanical components operating in diverse industries was elucidated. Furthermore, the effect of LC processes on mechanical properties such as wear, corrosion and fatigue properties are discussed. In addition, the LC process’s influence on microstructural features and microstructural modifications is explained. Finally, this study explores some potential applications of the LC process in diverse industries.

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48

Hall, Ernest L., та Ami E. Berkowitz. "Microstructural defects in γ-Fe2O3 particles". Journal of Materials Research 1, № 6 (грудень 1986): 836–44. http://dx.doi.org/10.1557/jmr.1986.0836.

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The microstructure of three different types of γ-Fe2O3 particles were examined using transmission electron microscopy. These included pure γ-Fe2O3, γ-Fe2O3 that had been surface modified using Co, and γ-Fe2O3 that had been doped with Co. The major internal microstructural defects found in the particles in all of the samples were pores and antiphase boundaries. Some particles also had a very high density of dislocations and low-angle boundaries. In general, the particles could be described as single crystals with symmetric cross section. The structure is based on a tetragonal unit cell, and each particle is divided into antiphase domains in which the c axis is oriented at 90°with respect to adjoining domains. The particles often exhibited very irregular shapes. No effect of Co modification was seen on the internal or surface structure of the particles. The Co-doped particles were found to be smaller in size and contained a lower density of internal defects. The effect of the microstructural defects and morphological irregularities in these particles on magnetic behavior is discussed.

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49

Dzhurinskiy, Dmitry, Abhishek Babu, Stanislav Dautov, Anil Lama, and Mayuribala Mangrulkar. "Modification of Cold-Sprayed Cu-Al-Ni-Al2O3 Composite Coatings by Friction Stir Technique to Enhance Wear Resistance Performance." Coatings 12, no. 8 (August 4, 2022): 1113. http://dx.doi.org/10.3390/coatings12081113.

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An innovative hybrid process combining two effective surface modification techniques, cold spray (CS) and friction stir processing (FSP), was proposed to refine the microstructure of Cu-Al-Ni-Al2O3 composite coating material. FSP was performed under constant rpm using extensive cooling conditions to remove heat generated during the operation. Microstructural characterizations such as optical micrography (OM), scanning electron microscopy (SEM), Electron Backscatter Diffraction (EBSD), Energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) were performed to evaluate the microstructural evolution of the coatings before and after FSP treatment. Mechanical characterizations such as microhardness and elastic modulus were measured using micro-depth sensing techniques. Furthermore, sliding wear tests were performed to study the wear resistance of the as-sprayed and processed coatings. The findings suggest that after FSP, there is an improvement in microstructure of the coating layers with the elimination of particle boundaries, micro-pores and micro-cracks, and processed coatings showed an improvement in mechanical properties. Furthermore, there was a slight reduction in the wear rate of the deposited CuAlNi-Al2O3 composite coatings. Among all the test coatings, friction stir processed S1 coating showed the lowest wear rate, which was an almost two times lower wear rate than its unprocessed counterparts.

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50

Ralston, K. D., J. G. Brunner, S. Virtanen, and N. Birbilis. "Effect of Processing on Grain Size and Corrosion of AA2024-T3." Corrosion 67, no. 10 (October 1, 2011): 105001–105001. http://dx.doi.org/10.5006/1.3647762.

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Abstract Recent works on high-purity materials have indicated that microstructural modification via grain refinement can alternately reduce or enhance corrosion, depending on the specific material-environment combination. Generally, however, a paucity of information exists in understanding how microstructural alteration and processing, in combination with grain refinement, affects corrosion. In this work, the effect of microstructural refinement on an alloy containing a high number density of precipitates and intermetallics is explored. Grain-refined AA2024-T3 (UNS A92024) samples were produced through severe plastic deformation processes and their corrosion response was compared to control samples of commercial ingot and sheet across the pH range. Microstructure and grain size were characterized using a combination of electron backscattered diffraction and transmission electron microscopy. It is revealed that there is a difference in corrosion between the specimens (which possess nearly the same bulk chemistry) as based on anodic potentiodynamic polarization, current transient, and exposure/profilometry experiments in sodium chloride (NaCl) electrolytes. However, in all cases, the effect is dominated by the environment, micro-chemical differences, and grain size.

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