Pub Date : 2026-01-21DOI: 10.1016/j.matchar.2026.116034
Ye Yuan , Yinsong Xie , Konghui Ma , Hong Liang , Zicheng Li , Yu Liu , Taisen Zuo , Zhaohui Dong , Hongying Yu , Dongbai Sun , Xin Xu
The microstructural evolution, mechanical response and corrosion behavior of a model super martensitic stainless steel (SMSS) Fe-13Cr-5Ni-3Cu tempered at 600 °C were systematically studied. A multiscale characterization approach combining synchrotron X-ray diffraction, small-angle neutron scattering, electron backscatter diffraction and transmission electron microscopy reveals the coupled evolution of Cu-rich precipitates (CRPs) and reversed austenite (RvA). CRPs exhibit sequential anisotropic growth, initially elongating along the long axis and subsequently coarsening along the short axis. Their number density and volume fraction peak at 1 h before declining with tempering time due to coarsening and coalescence. The interplay between CRPs and RvA governs the time-dependent mechanical and electrochemical properties of the alloy. Short-term tempering produces fine CRPs that maximize precipitation strengthening and strain hardening, yielding superior strength–ductility synergy, tensile strength of 868 MPa with 16% elongation for 1 h tempering, without sacrificing corrosion resistance. In contrast, prolonged tempering leads to CRP coarsening and RvA-induced softening, reduced strength and impaired pitting resistance. These results establish a clear process–microstructure–property relationship for Cu-bearing SMSSs, assisting the development of the next-generation SMSSs with optimized strength and corrosion resistance.
{"title":"Synergistic effect of Cu-rich precipitate and reversed austenite on mechanical property and corrosion resistance of Fe-13Cr-5Ni-3Cu super martensitic stainless steel","authors":"Ye Yuan , Yinsong Xie , Konghui Ma , Hong Liang , Zicheng Li , Yu Liu , Taisen Zuo , Zhaohui Dong , Hongying Yu , Dongbai Sun , Xin Xu","doi":"10.1016/j.matchar.2026.116034","DOIUrl":"10.1016/j.matchar.2026.116034","url":null,"abstract":"<div><div>The microstructural evolution, mechanical response and corrosion behavior of a model super martensitic stainless steel (SMSS) Fe-13Cr-5Ni-3Cu tempered at 600 °C were systematically studied. A multiscale characterization approach combining synchrotron X-ray diffraction, small-angle neutron scattering, electron backscatter diffraction and transmission electron microscopy reveals the coupled evolution of Cu-rich precipitates (CRPs) and reversed austenite (RvA). CRPs exhibit sequential anisotropic growth, initially elongating along the long axis and subsequently coarsening along the short axis. Their number density and volume fraction peak at 1 h before declining with tempering time due to coarsening and coalescence. The interplay between CRPs and RvA governs the time-dependent mechanical and electrochemical properties of the alloy. Short-term tempering produces fine CRPs that maximize precipitation strengthening and strain hardening, yielding superior strength–ductility synergy, tensile strength of 868 MPa with 16% elongation for 1 h tempering, without sacrificing corrosion resistance. In contrast, prolonged tempering leads to CRP coarsening and RvA-induced softening, reduced strength and impaired pitting resistance. These results establish a clear process–microstructure–property relationship for Cu-bearing SMSSs, assisting the development of the next-generation SMSSs with optimized strength and corrosion resistance.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"233 ","pages":"Article 116034"},"PeriodicalIF":5.5,"publicationDate":"2026-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146090595","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-21DOI: 10.1016/j.matchar.2026.116052
Bingxu Wang , Peng Li , Zhipeng Yuan , Yinghui Dong , Wenjun Yang , Zhaobing Cai , Le Gu
Under demanding operating conditions, mechanical equipment (such as rolling bearings) frequently experiences premature surface failure, leading to significantly reduced service life and economic losses. The performance of conventional physical vapor deposition films (such as TiN) has reached its limits, making it difficult to meet higher protective requirements. This work employed response surface methodology to optimize the cathode power, substrate temperature, and bias voltage during the magnetron sputtering process, ultimately successfully fabricating high-hardness AlNbTiZrN films (S1). The final optimized deposition parameters were established as follows: power 1600 W, temperature 400 °C, and bias voltage 200 V. Structural analysis revealed that the S1 film has a face-centered cubic structure, preferentially oriented along the (200) crystal plane. XPS analysis indicated that nitrogen atoms formed a solid solution with metal atoms. Compared with the control group (S2, parameters: power 1200 W, temperature 300 °C, bias 150 V), the S1 film showed a reduction in grain size and a dense, spherical particle surface morphology. Furthermore, the S1 film outperformed the S2 film in terms of H/E, H3/E2, and elastic recovery capability. Furthermore, the tribological properties of high-hardness AlNbTiZrN films were evaluated under various tribological test conditions, and their tribological behavior was analyzed. In the context of tribological testing (loads: 1–3 N; frequencies: 1–3 Hz) conditions, it was observed that the high-hardness AlNbTiZrN films exhibited reduced friction coefficients and augmented wear resistance. The analysis of tribological behavior indicated that the main wear mechanisms for high-hardness AlNbTiZrN films are three-body wear and oxidation wear, with no cracking or delamination during friction, demonstrating excellent suitability for high-frequency/ high-load conditions.
{"title":"High-hardness AlNbTiZrN films prepared by magnetron sputtering: Microstructural characterization, and tribological behavior","authors":"Bingxu Wang , Peng Li , Zhipeng Yuan , Yinghui Dong , Wenjun Yang , Zhaobing Cai , Le Gu","doi":"10.1016/j.matchar.2026.116052","DOIUrl":"10.1016/j.matchar.2026.116052","url":null,"abstract":"<div><div>Under demanding operating conditions, mechanical equipment (such as rolling bearings) frequently experiences premature surface failure, leading to significantly reduced service life and economic losses. The performance of conventional physical vapor deposition films (such as TiN) has reached its limits, making it difficult to meet higher protective requirements. This work employed response surface methodology to optimize the cathode power, substrate temperature, and bias voltage during the magnetron sputtering process, ultimately successfully fabricating high-hardness AlNbTiZrN films (S1). The final optimized deposition parameters were established as follows: power 1600 W, temperature 400 °C, and bias voltage 200 V. Structural analysis revealed that the S1 film has a face-centered cubic structure, preferentially oriented along the (200) crystal plane. XPS analysis indicated that nitrogen atoms formed a solid solution with metal atoms. Compared with the control group (S2, parameters: power 1200 W, temperature 300 °C, bias 150 V), the S1 film showed a reduction in grain size and a dense, spherical particle surface morphology. Furthermore, the S1 film outperformed the S2 film in terms of H/E, H<sup>3</sup>/E<sup>2</sup>, and elastic recovery capability. Furthermore, the tribological properties of high-hardness AlNbTiZrN films were evaluated under various tribological test conditions, and their tribological behavior was analyzed. In the context of tribological testing (loads: 1–3 N; frequencies: 1–3 Hz) conditions, it was observed that the high-hardness AlNbTiZrN films exhibited reduced friction coefficients and augmented wear resistance. The analysis of tribological behavior indicated that the main wear mechanisms for high-hardness AlNbTiZrN films are three-body wear and oxidation wear, with no cracking or delamination during friction, demonstrating excellent suitability for high-frequency/ high-load conditions.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"233 ","pages":"Article 116052"},"PeriodicalIF":5.5,"publicationDate":"2026-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146036778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-21DOI: 10.1016/j.matchar.2026.116050
Yihui Gao , Wei Guo , Zhu Li , Ming Liu , Haolin Zeng , Jianhua Yao
Nanosecond laser cleaning was employed to remove organic contaminants and oxide films from the surface of titanium alloy. The effects of laser fluence on surface morphology, roughness, elemental composition, oxide film thickness, and mechanical properties were systematically investigated employing Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), X-ray Photoelectron Spectroscopy (XPS), Transmission Electron Microscopy (TEM), and X-ray Diffraction (XRD). The original surface was covered with oil stains and oxygen-rich particles, with an oxide film approximately 10 nm thick. At a fluence of 6.11 J/cm2, surface contaminants were completely removed, the roughness decreased by 32%, the oxygen content reduced by 35%, and the oxide film thickness decreased to 3.6 nm without any observable surface damage. When the fluence was below 4.08 J/cm2, cleaning was incomplete, whereas fluences above 8.15 J/cm2 caused surface cracking. Further increasing the fluence beyond 10.18 J/cm2 resulted in ablation craters accompanied by oxide film thickening. Residual stress increased with rising fluence, while microhardness, yield strength, and tensile strength remained nearly unchanged, with a slight improvement in elongation, thereby confirming the non-destructive nature of the process. The analysis indicates that the cleaning mechanism is primarily driven by thermal ablation, accompanied by melting and localized secondary oxidation. This study provides valuable insights for optimizing non-destructive laser cleaning processes of titanium alloys prior to welding.
{"title":"Laser cleaning for titanium alloy: Surface quality and mechanism","authors":"Yihui Gao , Wei Guo , Zhu Li , Ming Liu , Haolin Zeng , Jianhua Yao","doi":"10.1016/j.matchar.2026.116050","DOIUrl":"10.1016/j.matchar.2026.116050","url":null,"abstract":"<div><div>Nanosecond laser cleaning was employed to remove organic contaminants and oxide films from the surface of titanium alloy. The effects of laser fluence on surface morphology, roughness, elemental composition, oxide film thickness, and mechanical properties were systematically investigated employing Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), X-ray Photoelectron Spectroscopy (XPS), Transmission Electron Microscopy (TEM), and X-ray Diffraction (XRD). The original surface was covered with oil stains and oxygen-rich particles, with an oxide film approximately 10 nm thick. At a fluence of 6.11 J/cm<sup>2</sup>, surface contaminants were completely removed, the roughness decreased by 32%, the oxygen content reduced by 35%, and the oxide film thickness decreased to 3.6 nm without any observable surface damage. When the fluence was below 4.08 J/cm<sup>2</sup>, cleaning was incomplete, whereas fluences above 8.15 J/cm<sup>2</sup> caused surface cracking. Further increasing the fluence beyond 10.18 J/cm<sup>2</sup> resulted in ablation craters accompanied by oxide film thickening. Residual stress increased with rising fluence, while microhardness, yield strength, and tensile strength remained nearly unchanged, with a slight improvement in elongation, thereby confirming the non-destructive nature of the process. The analysis indicates that the cleaning mechanism is primarily driven by thermal ablation, accompanied by melting and localized secondary oxidation. This study provides valuable insights for optimizing non-destructive laser cleaning processes of titanium alloys prior to welding.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"233 ","pages":"Article 116050"},"PeriodicalIF":5.5,"publicationDate":"2026-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146090588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-20DOI: 10.1016/j.matchar.2026.116047
Aishani Sharma , Jens Darsell , Dalong Zhang , Jia Liu , Kayla H. Yano , Tingkun Liu , Xiang Wang , Xiao Li , Mark Rhodes , Stuart Maloy , Eda Aydogan
The need for advanced materials in nuclear reactors has spotlighted ferritic oxide dispersion strengthened steels for their excellent high-temperature strength, irradiation resistance, and corrosion tolerance. However, conventional powder metallurgy routes such as mechanical alloying often involve multiple processing steps which are complex, time consuming and costly. Additionally, such techniques are often associated with microstructural inhomogeneities and defects. The current study introduces a novel friction extrusion process for producing fully consolidated oxide dispersion strengthened steel rods from powder precursors. The rods are subsequently machined into tubes with an approximate wall thickness of ∼1 mm by drilling holes through their center. The process leverages intense shear deformation at a reduced temperature (∼1000 °C) to achieve consolidation and uniform dispersion of oxides. As proof of concept, pilgering was applied to fabricate thin-walled cladding tubes of ∼0.5 mm wall thickness from the extruded tubes with uniform cross-sections. Microstructural and mechanical characterization confirmed a high dispersion of nanometric oxides (>1020/ m3) in both the extruded and pilgered tubes along with enhanced mechanical properties, comparable to those achieved via conventional methods.
{"title":"Successful cladding tube production for next gen fission reactors using friction extrusion and pilgering","authors":"Aishani Sharma , Jens Darsell , Dalong Zhang , Jia Liu , Kayla H. Yano , Tingkun Liu , Xiang Wang , Xiao Li , Mark Rhodes , Stuart Maloy , Eda Aydogan","doi":"10.1016/j.matchar.2026.116047","DOIUrl":"10.1016/j.matchar.2026.116047","url":null,"abstract":"<div><div>The need for advanced materials in nuclear reactors has spotlighted ferritic oxide dispersion strengthened steels for their excellent high-temperature strength, irradiation resistance, and corrosion tolerance. However, conventional powder metallurgy routes such as mechanical alloying often involve multiple processing steps which are complex, time consuming and costly. Additionally, such techniques are often associated with microstructural inhomogeneities and defects. The current study introduces a novel friction extrusion process for producing fully consolidated oxide dispersion strengthened steel rods from powder precursors. The rods are subsequently machined into tubes with an approximate wall thickness of ∼1 mm by drilling holes through their center. The process leverages intense shear deformation at a reduced temperature (∼1000 °C) to achieve consolidation and uniform dispersion of oxides. As proof of concept, pilgering was applied to fabricate thin-walled cladding tubes of ∼0.5 mm wall thickness from the extruded tubes with uniform cross-sections. Microstructural and mechanical characterization confirmed a high dispersion of nanometric oxides (>10<sup>20</sup>/ m<sup>3</sup>) in both the extruded and pilgered tubes along with enhanced mechanical properties, comparable to those achieved via conventional methods.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"233 ","pages":"Article 116047"},"PeriodicalIF":5.5,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146036781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-20DOI: 10.1016/j.matchar.2026.116048
Juntao Yuan , Wenhao Feng , Huihui Zhang , Xuanpeng Li , Fengling Tan , Jufeng Huang , Juantao Zhang , Anqing Fu
The present study investigated the corrosion behavior of 5Cr-0.5Cu steel in a simulated produced water solution from shale gas fields containing Sulfate-Reducing Bacteria (SRB). The investigation employed weight loss tests, ultra-depth microscopy, SEM, XPS, and FIB-TEM techniques. The results indicate that temperature exerts a substantial influence on the microstructure of the corrosion product film on the steel surface. In the presence of elevated levels of SRB activity at a lower temperature (30 °C), the formation of a dense biofilm composed of extracellular polymeric substances (EPS) is promoted. These substances contain elements such as carbon (C), oxygen (O), phosphorus (P), and sulfur (S). This process instigates localized microenvironmental alterations, resulting in exacerbated uniform corrosion and pitting corrosion with extended immersion duration. It has been established that at an elevated temperature of 90 °C, the activity of SRB is suppressed. Concurrently, a multilayer corrosion product film with a thickness of approximately 200 nm is formed on the steel surface. The composition of the film is such that it consists of an inner layer of Fe- and P-rich oxides and an outer layer of Si-rich oxides. The microbial corrosion inhibition mechanism of the 5Cr-0.5Cu steel can be attributable to two factors. Firstly, the bactericidal effect of copper ions is attributable to the dissolution of nanoscale FCC-structured Cu-rich precipitates. These precipitates migrate to the SRB cell surface, thereby inducing oxidative damage. Secondly, the barrier effect of the amorphous FePO4 film formed at the steel substrate/SRB interface, which prevents direct contact between bacteria and the substrate.
{"title":"A microstructural characterization of temperature-dependent microbial corrosion of 5Cr-0.5Cu steel in simulated SRB-containing shale gas field produced water","authors":"Juntao Yuan , Wenhao Feng , Huihui Zhang , Xuanpeng Li , Fengling Tan , Jufeng Huang , Juantao Zhang , Anqing Fu","doi":"10.1016/j.matchar.2026.116048","DOIUrl":"10.1016/j.matchar.2026.116048","url":null,"abstract":"<div><div>The present study investigated the corrosion behavior of 5Cr-0.5Cu steel in a simulated produced water solution from shale gas fields containing Sulfate-Reducing Bacteria (SRB). The investigation employed weight loss tests, ultra-depth microscopy, SEM, XPS, and FIB-TEM techniques. The results indicate that temperature exerts a substantial influence on the microstructure of the corrosion product film on the steel surface. In the presence of elevated levels of SRB activity at a lower temperature (30 °C), the formation of a dense biofilm composed of extracellular polymeric substances (EPS) is promoted. These substances contain elements such as carbon (C), oxygen (O), phosphorus (P), and sulfur (S). This process instigates localized microenvironmental alterations, resulting in exacerbated uniform corrosion and pitting corrosion with extended immersion duration. It has been established that at an elevated temperature of 90 °C, the activity of SRB is suppressed. Concurrently, a multilayer corrosion product film with a thickness of approximately 200 nm is formed on the steel surface. The composition of the film is such that it consists of an inner layer of Fe- and P-rich oxides and an outer layer of Si-rich oxides. The microbial corrosion inhibition mechanism of the 5Cr-0.5Cu steel can be attributable to two factors. Firstly, the bactericidal effect of copper ions is attributable to the dissolution of nanoscale FCC-structured Cu-rich precipitates. These precipitates migrate to the SRB cell surface, thereby inducing oxidative damage. Secondly, the barrier effect of the amorphous FePO<sub>4</sub> film formed at the steel substrate/SRB interface, which prevents direct contact between bacteria and the substrate.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"233 ","pages":"Article 116048"},"PeriodicalIF":5.5,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146036786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-20DOI: 10.1016/j.matchar.2026.116042
Linfu Zhang , Ziang Zhang , Kang Liu , Peng Zhang , Qiang Zhu , Jie Xu , Debin Shan , Guohua Fan , Bin Guo
Medium-entropy superalloys (MESAs) are effective candidates for next-generation wrought superalloys, yet their hot deformation behavior is not well understood. In this study, a novel MESA was subjected to isothermal compression tests over a wide range of temperatures (1040–1200 °C) and strain rates (0.01–10 s−1). The microstructures resulting from these varied deformation parameters were then systematically characterized and analyzed. It was found that the γ’ solvus temperature acts as a critical threshold, fundamentally governing microstructural evolution. Below the solvus, the strong pinning effect of the γ’ phase, combined with twins, provided multiple nucleation sites. This activated a complex interplay of discontinuous dynamic recrystallization (DDRX), continuous dynamic recrystallization (CDRX), particle-stimulated recrystallization (PSN), and twinning-induced recrystallization (TDRX), resulting in an ultrafine-grained structure. Conversely, above the solvus, recrystallization proceeded via a combination of DDRX and CDRX, making the final grain size highly sensitive to the thermomechanical parameters. This research advances the fundamental understanding of microstructure evolution and its associated deformation mechanisms in MESAs during hot deformation, providing critical guidance for optimizing the microstructure and mechanical properties of MESAs.
{"title":"Insight into the microstructure evolution and deformation mechanisms of a medium-entropy superalloy during hot deformation","authors":"Linfu Zhang , Ziang Zhang , Kang Liu , Peng Zhang , Qiang Zhu , Jie Xu , Debin Shan , Guohua Fan , Bin Guo","doi":"10.1016/j.matchar.2026.116042","DOIUrl":"10.1016/j.matchar.2026.116042","url":null,"abstract":"<div><div>Medium-entropy superalloys (MESAs) are effective candidates for next-generation wrought superalloys, yet their hot deformation behavior is not well understood. In this study, a novel MESA was subjected to isothermal compression tests over a wide range of temperatures (1040–1200 °C) and strain rates (0.01–10 s<sup>−1</sup>). The microstructures resulting from these varied deformation parameters were then systematically characterized and analyzed. It was found that the γ’ solvus temperature acts as a critical threshold, fundamentally governing microstructural evolution. Below the solvus, the strong pinning effect of the γ’ phase, combined with twins, provided multiple nucleation sites. This activated a complex interplay of discontinuous dynamic recrystallization (DDRX), continuous dynamic recrystallization (CDRX), particle-stimulated recrystallization (PSN), and twinning-induced recrystallization (TDRX), resulting in an ultrafine-grained structure. Conversely, above the solvus, recrystallization proceeded via a combination of DDRX and CDRX, making the final grain size highly sensitive to the thermomechanical parameters. This research advances the fundamental understanding of microstructure evolution and its associated deformation mechanisms in MESAs during hot deformation, providing critical guidance for optimizing the microstructure and mechanical properties of MESAs.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"233 ","pages":"Article 116042"},"PeriodicalIF":5.5,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146026007","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-20DOI: 10.1016/j.matchar.2026.116021
Jani Penttilä , Tuomo Nyyssönen , Veli-Tapani Kuokkala , Lassi Raami , Pasi Peura
This study introduces a fast and cost-effective method for accurate crystallographic orientation determination from slip patterns of four and three traces, and from two traces with limited certainty. The method combines established graph-based and trigonometric methods and adds three new key elements: subsequent uniaxial stresses in X and Y directions, dark-field microscopy, and Schmid’s law. Developed for face centered cubic (FCC) materials with low stacking fault energy and annealed structures, the method utilizes MATLAB-based algorithms and custom-built image processing software for enhanced efficiency. Its accuracy is validated against electron backscatter diffraction (EBSD) data collected prior to compression testing and slip pattern analysis. The developed software tools are made available with the study. This method offers significant potential for efficient texture and slip trace analysis.
{"title":"Schmid factor aided slip pattern analysis; A method for determination of orientations of FCC crystals from slip traces","authors":"Jani Penttilä , Tuomo Nyyssönen , Veli-Tapani Kuokkala , Lassi Raami , Pasi Peura","doi":"10.1016/j.matchar.2026.116021","DOIUrl":"10.1016/j.matchar.2026.116021","url":null,"abstract":"<div><div>This study introduces a fast and cost-effective method for accurate crystallographic orientation determination from slip patterns of four and three traces, and from two traces with limited certainty. The method combines established graph-based and trigonometric methods and adds three new key elements: subsequent uniaxial stresses in X and Y directions, dark-field microscopy, and Schmid’s law. Developed for face centered cubic (FCC) materials with low stacking fault energy and annealed structures, the method utilizes MATLAB-based algorithms and custom-built image processing software for enhanced efficiency. Its accuracy is validated against electron backscatter diffraction (EBSD) data collected prior to compression testing and slip pattern analysis. The developed software tools are made available with the study. This method offers significant potential for efficient texture and slip trace analysis.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"233 ","pages":"Article 116021"},"PeriodicalIF":5.5,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146036780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-20DOI: 10.1016/j.matchar.2026.116040
Zhiqiang Li , Zhuo Song , Baifeng Dong , Li Wu , Hua Hou , Yuhong Zhao
In the process of large plastic deformation of hot piercing of seamless steel tubes, the initial microstructure state and the softening-hardening transition mechanism under long-range large strain conditions are extremely important for the precise control of hot piercing process of seamless steel tubes in actual production. The hot deformation behavior and softening-hardening interaction mechanism of S30432 in a wide temperature range of 900 °C–1150 °C and a wide strain rate range of 0.001 s−1–1 s−1 were systematically studied. By establishing an accurate hot processing map, the optimal hot processing window is 1100–1150 °C, 0.1–1 s−1, and the actual hot piercing seamless pipe production process is optimized. For the first time, the three hot working states of positive work hardening-rehardening cyclic fluctuation, steady-state rheological state and negative work hardening-rehardening transition dominated by heterogeneous gradient structure under long-range large strain conditions are revealed. The rehardening mechanism under the condition of long-range large strain is derived from the dual contribution of the long-range back stress generated by the dislocation proliferation of the rheological structure in the heart and the heterogeneous deformation induced hardening generated by the heterogeneous gradient structure of the deformation section. This finding can provide a reference for the study of the transformation of strengthening mechanism caused by microstructure changes such as gradient structure in the process of large plastic deformation of metal materials.
{"title":"Hot piercing deformation behavior and dynamic softening-rehardening transition mechanism of S30432","authors":"Zhiqiang Li , Zhuo Song , Baifeng Dong , Li Wu , Hua Hou , Yuhong Zhao","doi":"10.1016/j.matchar.2026.116040","DOIUrl":"10.1016/j.matchar.2026.116040","url":null,"abstract":"<div><div>In the process of large plastic deformation of hot piercing of seamless steel tubes, the initial microstructure state and the softening-hardening transition mechanism under long-range large strain conditions are extremely important for the precise control of hot piercing process of seamless steel tubes in actual production. The hot deformation behavior and softening-hardening interaction mechanism of S30432 in a wide temperature range of 900 °C–1150 °C and a wide strain rate range of 0.001 s<sup>−1</sup>–1 s<sup>−1</sup> were systematically studied. By establishing an accurate hot processing map, the optimal hot processing window is 1100–1150 °C, 0.1–1 s<sup>−1</sup>, and the actual hot piercing seamless pipe production process is optimized. For the first time, the three hot working states of positive work hardening-rehardening cyclic fluctuation, steady-state rheological state and negative work hardening-rehardening transition dominated by heterogeneous gradient structure under long-range large strain conditions are revealed. The rehardening mechanism under the condition of long-range large strain is derived from the dual contribution of the long-range back stress generated by the dislocation proliferation of the rheological structure in the heart and the heterogeneous deformation induced hardening generated by the heterogeneous gradient structure of the deformation section. This finding can provide a reference for the study of the transformation of strengthening mechanism caused by microstructure changes such as gradient structure in the process of large plastic deformation of metal materials.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"233 ","pages":"Article 116040"},"PeriodicalIF":5.5,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146090520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-20DOI: 10.1016/j.matchar.2026.116043
Yu-Sheng Lin , Cheng-Chih Hsiang , Yi-Chia Chou
Understanding the deformation mechanisms in Cu microwires is essential for enhancing their performance in advanced electronics and interconnect technologies. In this study, the deformation behavior of bamboo-type copper (Cu) microwires subjected to high-temperature point-contact reactions were systematically examined using electron backscatter diffraction (EBSD) combined with scanning electron microscopy (SEM). Key geometrical parameters—including the Luster-Morris parameter (m’), residual Burgers vector (Δb), and Schmid factor—were analyzed to elucidate slip deformation processes. The results revealed marked distinctions in slip transfer characteristics between bamboo segment interiors and segment boundaries. Grain boundaries consistently exhibited higher Δb and lower m’ values, indicating significant barriers to dislocation movement and resulting in pronounced localized deformation. In contrast, grain interiors demonstrated higher m’ and lower Δb values, facilitating more effective slip transfer. Statistical analysis indicated that misorientation angles exceeding 50° were common within grain segments, while fewer high-angle boundaries occurred at segment junctions, implying structural disfavorability. Furthermore, parameters Δb and the combined m’/Δb were confirmed as reliable quantitative indicators for differentiating slip compatibility between grain interiors and boundaries. This study provides novel insights into grain boundary deformation behaviors specific to high-temperature processed bamboo-type Cu microwires, bridging existing knowledge gaps and informing strategies to optimize their mechanical performance.
{"title":"Slip transfer analysis of copper microwires observed via point contact reaction","authors":"Yu-Sheng Lin , Cheng-Chih Hsiang , Yi-Chia Chou","doi":"10.1016/j.matchar.2026.116043","DOIUrl":"10.1016/j.matchar.2026.116043","url":null,"abstract":"<div><div>Understanding the deformation mechanisms in Cu microwires is essential for enhancing their performance in advanced electronics and interconnect technologies. In this study, the deformation behavior of bamboo-type copper (Cu) microwires subjected to high-temperature point-contact reactions were systematically examined using electron backscatter diffraction (EBSD) combined with scanning electron microscopy (SEM). Key geometrical parameters—including the Luster-Morris parameter (m’), residual Burgers vector (Δb), and Schmid factor—were analyzed to elucidate slip deformation processes. The results revealed marked distinctions in slip transfer characteristics between bamboo segment interiors and segment boundaries. Grain boundaries consistently exhibited higher Δb and lower m’ values, indicating significant barriers to dislocation movement and resulting in pronounced localized deformation. In contrast, grain interiors demonstrated higher m’ and lower Δb values, facilitating more effective slip transfer. Statistical analysis indicated that misorientation angles exceeding 50° were common within grain segments, while fewer high-angle boundaries occurred at segment junctions, implying structural disfavorability. Furthermore, parameters Δb and the combined m’/Δb were confirmed as reliable quantitative indicators for differentiating slip compatibility between grain interiors and boundaries. This study provides novel insights into grain boundary deformation behaviors specific to high-temperature processed bamboo-type Cu microwires, bridging existing knowledge gaps and informing strategies to optimize their mechanical performance.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"233 ","pages":"Article 116043"},"PeriodicalIF":5.5,"publicationDate":"2026-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146090594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-19DOI: 10.1016/j.matchar.2026.116033
Yu Wang , Yu Lu , D.O. Stukalin , Konglan Meng , E.R. Mamedova , Yuecheng Dong , Igor V. Alexandrov , Guohua Fan
In the present study, corrosion behavior of nanocrystalline Ti-2Fe-0.1B alloy after heat treatment during 300-450 °C was studied. The original grain size of Ti-2Fe-0.1B alloy by high-pressure torsion (HPT) at 6 GPa, 1 rpm and 5 turns can reach to 20 nm. Accompany with the temperature from increased 300 °C to 450 °C, the grain size presented an increased tendency. Concurrently, electrochemical test shows that the corrosion rate decreased from 2.74 × 10-4 mm·a-1 to 1.22 × 10-4 mm·a-1 (a reduction of ∼55%). This contradicts the conventional understanding that corrosion resistance decreases with increasing grain size. Further analysis indicates that the improvement of corrosion resistance can be attributed to the transformation during heat treatment, which decreases the number of point defects (e.g., oxygen vacancies and cation interstitials) incorporated into the passive film, then resulting in a denser and more stable film. Moreover, the -phase provides nucleation sites for α precipitation, further stabilizing the microstructure and resisting localized corrosion. In terms of mechanical properties, annealing led to a slight reduction in strength and hardness (UTS 1568 → 1327 MPa, HV 483 → 363), a minor increase in ductility (1.09 → 1.14%), and improved hardness uniformity. The core conclusion of this work is that correlating -phase fraction with the defect chemistry of passive films elucidates the role of the -phase in nanocrystalline Ti-2Fe-0.1B alloys. These findings demonstrate that heat treatment is an effective strategy to regulate -phase mediated defect chemistry and thereby enhance the corrosion resistance of nanocrystalline Ti-2Fe-0.1B alloys, providing practical guidance for the design of -stabilized titanium alloys with superior corrosion resistance.
{"title":"Enhanced corrosion behavior of nanocrystalline Ti-2Fe-0.1B alloy by ω phase transformation during heat treatment","authors":"Yu Wang , Yu Lu , D.O. Stukalin , Konglan Meng , E.R. Mamedova , Yuecheng Dong , Igor V. Alexandrov , Guohua Fan","doi":"10.1016/j.matchar.2026.116033","DOIUrl":"10.1016/j.matchar.2026.116033","url":null,"abstract":"<div><div>In the present study, corrosion behavior of nanocrystalline Ti-2Fe-0.1B alloy after heat treatment during 300-450 °C was studied. The original grain size of Ti-2Fe-0.1B alloy by high-pressure torsion (HPT) at 6 GPa, 1 rpm and 5 turns can reach to 20 nm. Accompany with the temperature from increased 300 °C to 450 °C, the grain size presented an increased tendency. Concurrently, electrochemical test shows that the corrosion rate decreased from 2.74 × 10<sup>-4</sup> mm·a<sup>-1</sup> to 1.22 × 10<sup>-4</sup> mm·a<sup>-1</sup> (a reduction of ∼55%). This contradicts the conventional understanding that corrosion resistance decreases with increasing grain size. Further analysis indicates that the improvement of corrosion resistance can be attributed to the <span><math><mi>ω</mi><mo>→</mo><mi>α</mi><mo>/</mo><mi>β</mi></math></span> transformation during heat treatment, which decreases the number of point defects (e.g., oxygen vacancies and cation interstitials) incorporated into the passive film, then resulting in a denser and more stable film. Moreover, the <span><math><mi>ω</mi></math></span>-phase provides nucleation sites for α precipitation, further stabilizing the microstructure and resisting localized corrosion. In terms of mechanical properties, annealing led to a slight reduction in strength and hardness (UTS 1568 → 1327 MPa, HV 483 → 363), a minor increase in ductility (1.09 → 1.14%), and improved hardness uniformity. The core conclusion of this work is that correlating <span><math><mi>ω</mi></math></span>-phase fraction with the defect chemistry of passive films elucidates the role of the <span><math><mi>ω</mi></math></span>-phase in nanocrystalline Ti-2Fe-0.1B alloys. These findings demonstrate that heat treatment is an effective strategy to regulate <span><math><mi>ω</mi></math></span>-phase mediated defect chemistry and thereby enhance the corrosion resistance of nanocrystalline Ti-2Fe-0.1B alloys, providing practical guidance for the design of <span><math><mi>β</mi></math></span>-stabilized titanium alloys with superior corrosion resistance.</div></div>","PeriodicalId":18727,"journal":{"name":"Materials Characterization","volume":"233 ","pages":"Article 116033"},"PeriodicalIF":5.5,"publicationDate":"2026-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146036779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}