Pub Date : 2025-04-22DOI: 10.1016/j.intermet.2025.108794
Mingjun Qiu , Ping Huang , Chao Gu , Fei Wang
In contrast to the successful realization of strength-ductility synergy through local chemical ordering (LCO) in FCC systems, achieving similar effects in BCC structures remains challenging. The complex core structure of BCC dislocations leads to an opposite hindrance effect of LCO on screw dislocations compared to FCC systems, necessitating compositional design to optimize LCO distribution and morphology. Guided by the negative enthalpy alloy design philosophy, this study introduces high-density LCO in the V950 alloy. By modulating the synergistic interaction between LCO and texture, the alloy achieves exceptional mechanical properties, including ultrahigh yield strength (∼960 MPa), ultimate tensile strength (1159 MPa), and fracture elongation (∼27.5 %), surpassing most reported refractory high-entropy alloys (RHEAs). Furthermore, this work elucidates novel mechanisms of work hardening behavior in BCC-structured alloys, advancing fundamental understanding and design strategies for high-performance BCC systems.
{"title":"Achieving superior strength–ductility synergy in refractory high entropy alloy","authors":"Mingjun Qiu , Ping Huang , Chao Gu , Fei Wang","doi":"10.1016/j.intermet.2025.108794","DOIUrl":"10.1016/j.intermet.2025.108794","url":null,"abstract":"<div><div>In contrast to the successful realization of strength-ductility synergy through local chemical ordering (LCO) in FCC systems, achieving similar effects in BCC structures remains challenging. The complex core structure of BCC dislocations leads to an opposite hindrance effect of LCO on screw dislocations compared to FCC systems, necessitating compositional design to optimize LCO distribution and morphology. Guided by the negative enthalpy alloy design philosophy, this study introduces high-density LCO in the V950 alloy. By modulating the synergistic interaction between LCO and texture, the alloy achieves exceptional mechanical properties, including ultrahigh yield strength (∼960 MPa), ultimate tensile strength (1159 MPa), and fracture elongation (∼27.5 %), surpassing most reported refractory high-entropy alloys (RHEAs). Furthermore, this work elucidates novel mechanisms of work hardening behavior in BCC-structured alloys, advancing fundamental understanding and design strategies for high-performance BCC systems.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"183 ","pages":"Article 108794"},"PeriodicalIF":4.3,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143860743","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 : 2025-04-22DOI: 10.1016/j.intermet.2025.108796
Dongdong Xia , Haiping Guo , Xicong Ye , Zhongheng Diao , Luer Yu , Huijun Kang , Guangwei Zhao , Bo Li , Dong Fang
The triphase composite eutectic high-entropy alloys, (NiAl)x(CoCrFeNi)94-xTa6 (x = 12, 15, 17, 23, 28, 34), were designed and prepared using the pseudo-ternary method, and the microstructures and mechanical properties were investigated. The vertical section phase diagram of the pseudo-ternary eutectic at Ta = 6 at. % was plotted on the basis of the principle of solid-state immiscibility. The theoretical solidification paths are likely to be different from the actual solidification paths due to the finite solid solution in the solid state, the nonequilibrium solidification, and the sluggish diffusion effect of high-entropy alloys. In this study, all developed alloys consist of the primary phase, biphase, and triphase eutectics. The primary phase of NiAl-12, NiAl-15, NiAl-17, and NiAl-23 alloys is FCC phase, while that of NiAl-28 and NiAl-34 alloys is the B2 phase. When the primary phase is B2, it is rich in nanoprecipitates with BCC structure. The synergistic effects of the B2 and Laves phases reinforce the overall mechanical properties of the CoCrFeNi high-entropy alloy. In particular, the NiAl-15 alloy displays superior overall mechanical properties, with high yield strength, fracture strength, and maximum compressive strain values of 859.1 MPa, 2559.5 MPa, and 41.6 %, respectively. The yield strength of NiAl-15 alloy is calculated based on the mixing rule, and the results show that the strength is mainly contributed by the Laves phase.
{"title":"Effect of NiAl content on microstructure and properties of (NiAl)x(CoCrFeNi)94-xTa6 alloy","authors":"Dongdong Xia , Haiping Guo , Xicong Ye , Zhongheng Diao , Luer Yu , Huijun Kang , Guangwei Zhao , Bo Li , Dong Fang","doi":"10.1016/j.intermet.2025.108796","DOIUrl":"10.1016/j.intermet.2025.108796","url":null,"abstract":"<div><div>The triphase composite eutectic high-entropy alloys, (NiAl)<sub>x</sub>(CoCrFeNi)<sub>94-x</sub>Ta<sub>6</sub> (x = 12, 15, 17, 23, 28, 34), were designed and prepared using the pseudo-ternary method, and the microstructures and mechanical properties were investigated. The vertical section phase diagram of the pseudo-ternary eutectic at Ta = 6 at. % was plotted on the basis of the principle of solid-state immiscibility. The theoretical solidification paths are likely to be different from the actual solidification paths due to the finite solid solution in the solid state, the nonequilibrium solidification, and the sluggish diffusion effect of high-entropy alloys. In this study, all developed alloys consist of the primary phase, biphase, and triphase eutectics. The primary phase of NiAl-12, NiAl-15, NiAl-17, and NiAl-23 alloys is FCC phase, while that of NiAl-28 and NiAl-34 alloys is the B2 phase. When the primary phase is B2, it is rich in nanoprecipitates with BCC structure. The synergistic effects of the B2 and Laves phases reinforce the overall mechanical properties of the CoCrFeNi high-entropy alloy. In particular, the NiAl-15 alloy displays superior overall mechanical properties, with high yield strength, fracture strength, and maximum compressive strain values of 859.1 MPa, 2559.5 MPa, and 41.6 %, respectively. The yield strength of NiAl-15 alloy is calculated based on the mixing rule, and the results show that the strength is mainly contributed by the Laves phase.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"183 ","pages":"Article 108796"},"PeriodicalIF":4.3,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143860744","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}
Impact resistance is the most important factor affecting the reliability of TiAl alloy blades used in jet engines. We evaluated the impact resistance of TiAl4822 and TNM alloy based on the expected service environment to understand the performance of the actual product blade. Using the surface cut by a diamond grinding wheel as a reference, the impact resistance, including that of the machined surface (under light load) and the oxidized surface (700 °C for 1000 h) was evaluated at room temperature (25 °C), 500 °C, and 700 °C using the Charpy impact test. Both alloys' impact resistance decreased to 70–90 % of the reference values at all temperatures, owing to the microscopic defects on the machined surface. Heating alone (i.e., evaluating the interior of the material after the oxidation test) did not affect the impact resistance of both the alloys. Oxidation hardly affected the impact resistance of TiAl4822 but resulted in a significant decrease in the impact resistance of TNM alloy at all temperatures. This is attributed to the presence of the altered layer under the oxide and nitride layers of TNM alloy, which contains fine βo-phase precipitates. The high-temperature impact resistance of the TNM alloy after oxidation (which is the most important factor in the reliability of TiAl alloy blades) was less than half that of TiAl4822. Considering factors such as cost, material properties, and reliability, TiAl4822 is considerably superior to TNM alloy for application in jet engine blades.
{"title":"Comparison of the impact resistance of TiAl4822 and TNM alloy under expected service conditions of jet engine blades","authors":"Toshimitsu Tetsui , Taketo Fukuyo , Kazuhiro Mizuta","doi":"10.1016/j.intermet.2025.108793","DOIUrl":"10.1016/j.intermet.2025.108793","url":null,"abstract":"<div><div>Impact resistance is the most important factor affecting the reliability of TiAl alloy blades used in jet engines. We evaluated the impact resistance of TiAl4822 and TNM alloy based on the expected service environment to understand the performance of the actual product blade. Using the surface cut by a diamond grinding wheel as a reference, the impact resistance, including that of the machined surface (under light load) and the oxidized surface (700 °C for 1000 h) was evaluated at room temperature (25 °C), 500 °C, and 700 °C using the Charpy impact test. Both alloys' impact resistance decreased to 70–90 % of the reference values at all temperatures, owing to the microscopic defects on the machined surface. Heating alone (i.e., evaluating the interior of the material after the oxidation test) did not affect the impact resistance of both the alloys. Oxidation hardly affected the impact resistance of TiAl4822 but resulted in a significant decrease in the impact resistance of TNM alloy at all temperatures. This is attributed to the presence of the altered layer under the oxide and nitride layers of TNM alloy, which contains fine β<sub>o</sub>-phase precipitates. The high-temperature impact resistance of the TNM alloy after oxidation (which is the most important factor in the reliability of TiAl alloy blades) was less than half that of TiAl4822. Considering factors such as cost, material properties, and reliability, TiAl4822 is considerably superior to TNM alloy for application in jet engine blades.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"183 ","pages":"Article 108793"},"PeriodicalIF":4.3,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850669","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 : 2025-04-19DOI: 10.1016/j.intermet.2025.108792
Mengmeng Zhao , Jun Wang , Hongchao Li , Haoxue Yang , Yu Zhou , Jinshan Li
FCC high-entropy alloys (HEAs) exhibit excellent strain hardening capabilities at both room and cryogenic conditions due to deformation mechanisms such as twinning and stacking faults. Recent studies have focused on further enhancing the strength of FCC (face-centered cubic) HEAs through grain refinement. However, the impact of grain size on the mechanical properties and deformation behavior of these alloys still requires further investigation. This study examines the microstructure and mechanical behavior of Al0.25CoCrFeNi HEA with three distinct grain sizes. As the grain size decreases, the yield strength at both 25 °C and −196 °C increases due to grain boundary strengthening. Notably, the Hall-Petch coefficient at −196 °C is slightly higher than that at 25 °C. At 25 °C, the deformation mechanism transitions from dislocation slip to deformation twinning as the grain size increases. At −196 °C, deformation twins are observed in fine-grained samples, with their density increasing and spacing decreasing as the grain size increases. The refinement of nanotwins promotes a dynamic Hall-Petch effect and enhances the strength-ductility balance, attributing to the increase in flow stress and the reduction in stacking fault energy at −196 °C. This study provides valuable insights into the effect of grain size on the deformation mechanisms of alloys at room and cryogenic temperatures.
{"title":"Grain size effects on mechanical behavior of Al0.25CoCrFeNi high-entropy alloy at room and cryogenic temperatures","authors":"Mengmeng Zhao , Jun Wang , Hongchao Li , Haoxue Yang , Yu Zhou , Jinshan Li","doi":"10.1016/j.intermet.2025.108792","DOIUrl":"10.1016/j.intermet.2025.108792","url":null,"abstract":"<div><div>FCC high-entropy alloys (HEAs) exhibit excellent strain hardening capabilities at both room and cryogenic conditions due to deformation mechanisms such as twinning and stacking faults. Recent studies have focused on further enhancing the strength of FCC (face-centered cubic) HEAs through grain refinement. However, the impact of grain size on the mechanical properties and deformation behavior of these alloys still requires further investigation. This study examines the microstructure and mechanical behavior of Al<sub>0.25</sub>CoCrFeNi HEA with three distinct grain sizes. As the grain size decreases, the yield strength at both 25 °C and −196 °C increases due to grain boundary strengthening. Notably, the Hall-Petch coefficient at −196 °C is slightly higher than that at 25 °C. At 25 °C, the deformation mechanism transitions from dislocation slip to deformation twinning as the grain size increases. At −196 °C, deformation twins are observed in fine-grained samples, with their density increasing and spacing decreasing as the grain size increases. The refinement of nanotwins promotes a dynamic Hall-Petch effect and enhances the strength-ductility balance, attributing to the increase in flow stress and the reduction in stacking fault energy at −196 °C. This study provides valuable insights into the effect of grain size on the deformation mechanisms of alloys at room and cryogenic temperatures.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"183 ","pages":"Article 108792"},"PeriodicalIF":4.3,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850668","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 : 2025-04-14DOI: 10.1016/j.intermet.2025.108784
Chengcheng Shi , Yongkang Liu , Yuelong Yuan , Dekai Liu , Rui Liu , Zhen Lu , Nana Guo , Jinzhao Sun
The influence of sintering parameters on the microstructural evolution and mechanical properties of Ti-46.5Al-2Cr-1.8Nb-0.2W-0.15B (at.%) alloys fabricated via hot press sintering by adopting pre-alloyed powders are investigated in detail. The results indicated that the alloys were composed of heterogeneous microstructure caused by localized recrystallization and original powder boundaries (OPBs), when densified at insufficient sintering parameters. Hence, the alloys cracked at the interface of heterogeneoum icrostructure or OPBs due to the discontinuity of deformation, resulting in a relative low mechanical property at 800 °C and the hot workability. With increasing the sintering temperature and holding time to 1300 °C and 120min, respectively, the OPBs and heterogeneous microstructure faded away, and the fracture mechanism transformed into micro-void development at the interfaces of deformation twin groups and the DRX grains, which lead to the increase of plasticity. Further increasing the sintering temperature or holding time, the comprehensive mechanical properties decreased due to the coarsening of microstructure. Therefore, the optimal sintering parameters were considered as sintering at 1300 °C with a holding time of 120min. This research can provide a scientific reference for the preparation of high-performance TiAl based alloys by powder metallurgy method.
{"title":"Achieving high performance HPS TiAl based alloy by adjusting sintering process parameters to eliminate heterogeneous microstructure and original powder boundaries","authors":"Chengcheng Shi , Yongkang Liu , Yuelong Yuan , Dekai Liu , Rui Liu , Zhen Lu , Nana Guo , Jinzhao Sun","doi":"10.1016/j.intermet.2025.108784","DOIUrl":"10.1016/j.intermet.2025.108784","url":null,"abstract":"<div><div>The influence of sintering parameters on the microstructural evolution and mechanical properties of Ti-46.5Al-2Cr-1.8Nb-0.2W-0.15B (at.%) alloys fabricated via hot press sintering by adopting pre-alloyed powders are investigated in detail. The results indicated that the alloys were composed of heterogeneous microstructure caused by localized recrystallization and original powder boundaries (OPBs), when densified at insufficient sintering parameters. Hence, the alloys cracked at the interface of heterogeneoum icrostructure or OPBs due to the discontinuity of deformation, resulting in a relative low mechanical property at 800 °C and the hot workability. With increasing the sintering temperature and holding time to 1300 °C and 120min, respectively, the OPBs and heterogeneous microstructure faded away, and the fracture mechanism transformed into micro-void development at the interfaces of deformation twin groups and the DRX grains, which lead to the increase of plasticity. Further increasing the sintering temperature or holding time, the comprehensive mechanical properties decreased due to the coarsening of microstructure. Therefore, the optimal sintering parameters were considered as sintering at 1300 °C with a holding time of 120min. This research can provide a scientific reference for the preparation of high-performance TiAl based alloys by powder metallurgy method.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"182 ","pages":"Article 108784"},"PeriodicalIF":4.3,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143829885","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 : 2025-04-12DOI: 10.1016/j.intermet.2025.108788
Xiaowen Xu , Hongyou Bian , Weijun Liu , Fei Xing , Boxue Song
Addition of WC ceramic particles is an effective method to improve mechanical properties of coatings. To improve the wear properties of the T-800 alloy coating, Tribaloy T-800 and Tribaloy T-800/WC composite coatings are deposited on the DZ125 alloy by laser cladding. The influence mechanisms of WC contents (0 wt%, 5 wt%, 10 wt%) on the precipitation behavior of the Laves phase (Co3Mo2Si) and secondary phases, microhardness, and wear performance are systematically studied. The results show that the addition of WC promotes an increase in the Laves phase content and size reduction as well as an improvement in the dislocation density of the composite coating. As the WC content is increased from 0 wt% to 10 wt%, the Laves phase content increases from 30.5 % to 45.5 %, the average size reduces from 10.2 μm to 10.3 μm and the average KAM value rises from 0.58° to 0.81°. Moreover, after the addition of WC, additional WC phase, W2C phase and Co6Mo6C phase appear in the composite coating, and the content of these secondary phases shows an upward trend with increasing WC content. The microhardness and wear properties of the composite coating are significantly improved by the evolution of the microstructure. The microhardness and wear properties of the composite coating are optimized when the WC content is 10 wt%. Compared to the coating without WC, the composite coating with 10 wt% WC increases the microhardness by 18.3 % and reduces the wear mass loss by 37.9 %.
{"title":"Microstructure and mechanical properties of Tribaloy T-800/WC composite coatings deposited on DZ125 directionally solidified alloy by laser cladding","authors":"Xiaowen Xu , Hongyou Bian , Weijun Liu , Fei Xing , Boxue Song","doi":"10.1016/j.intermet.2025.108788","DOIUrl":"10.1016/j.intermet.2025.108788","url":null,"abstract":"<div><div>Addition of WC ceramic particles is an effective method to improve mechanical properties of coatings. To improve the wear properties of the T-800 alloy coating, Tribaloy T-800 and Tribaloy T-800/WC composite coatings are deposited on the DZ125 alloy by laser cladding. The influence mechanisms of WC contents (0 wt%, 5 wt%, 10 wt%) on the precipitation behavior of the Laves phase (Co<sub>3</sub>Mo<sub>2</sub>Si) and secondary phases, microhardness, and wear performance are systematically studied. The results show that the addition of WC promotes an increase in the Laves phase content and size reduction as well as an improvement in the dislocation density of the composite coating. As the WC content is increased from 0 wt% to 10 wt%, the Laves phase content increases from 30.5 % to 45.5 %, the average size reduces from 10.2 μm to 10.3 μm and the average KAM value rises from 0.58° to 0.81°. Moreover, after the addition of WC, additional WC phase, W<sub>2</sub>C phase and Co<sub>6</sub>Mo<sub>6</sub>C phase appear in the composite coating, and the content of these secondary phases shows an upward trend with increasing WC content. The microhardness and wear properties of the composite coating are significantly improved by the evolution of the microstructure. The microhardness and wear properties of the composite coating are optimized when the WC content is 10 wt%. Compared to the coating without WC, the composite coating with 10 wt% WC increases the microhardness by 18.3 % and reduces the wear mass loss by 37.9 %.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"182 ","pages":"Article 108788"},"PeriodicalIF":4.3,"publicationDate":"2025-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143824703","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 : 2025-04-11DOI: 10.1016/j.intermet.2025.108791
Shujian Zhou , Shilu Chen , Peng Du , Rongqiang Yan , Bo Yuan , Zeyun Cai , Liang Zhang , Guoqiang Xie
The inherent brittleness and unideal degradation rate of Mg-Zn-Ca bulk metallic glass (BMG) pose significant challenges for its application as degradable biomaterials. To address this issue, we introduced a non-toxic, highly ductile Sn-Zn alloy as a secondary phase within the powder metallurgy Mg-Zn-Ca BMG, resulting in a notable enhancement in plasticity. This study further investigates the impact of the Sn-Zn reinforced phase on the corrosion behavior of the BMG in Hank's solution. Our findings reveal that the Mg-Zn-Ca/Sn-Zn BMG composite not only surpasses the corrosion resistance of the Mg-Zn-Ca BMG, but also ranks among the most advanced biomedical Mg alloys reported to date. Importantly, the Mg-Zn-Ca/Sn-Zn BMG composite retains adequate strength and plasticity even after extended degradation, marking a significant advancement in the development of large-scale Mg-based medical metallic glasses.
{"title":"Simultaneously improving the plasticity and corrosion resistance of biomedical Mg-based bulk metallic glass by introducing SnZn alloy solder","authors":"Shujian Zhou , Shilu Chen , Peng Du , Rongqiang Yan , Bo Yuan , Zeyun Cai , Liang Zhang , Guoqiang Xie","doi":"10.1016/j.intermet.2025.108791","DOIUrl":"10.1016/j.intermet.2025.108791","url":null,"abstract":"<div><div>The inherent brittleness and unideal degradation rate of Mg-Zn-Ca bulk metallic glass (BMG) pose significant challenges for its application as degradable biomaterials. To address this issue, we introduced a non-toxic, highly ductile Sn-Zn alloy as a secondary phase within the powder metallurgy Mg-Zn-Ca BMG, resulting in a notable enhancement in plasticity. This study further investigates the impact of the Sn-Zn reinforced phase on the corrosion behavior of the BMG in Hank's solution. Our findings reveal that the Mg-Zn-Ca/Sn-Zn BMG composite not only surpasses the corrosion resistance of the Mg-Zn-Ca BMG, but also ranks among the most advanced biomedical Mg alloys reported to date. Importantly, the Mg-Zn-Ca/Sn-Zn BMG composite retains adequate strength and plasticity even after extended degradation, marking a significant advancement in the development of large-scale Mg-based medical metallic glasses.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"182 ","pages":"Article 108791"},"PeriodicalIF":4.3,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143821377","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 : 2025-04-09DOI: 10.1016/j.intermet.2025.108789
Hengming Hu , Caiyun Liu , Zihuai Su , Feng Ye , Bin Qian , Ye Dai , Shengzhi Sun , Binbin Liu , Jianrong Qiu
The unique atomic packing of amorphous alloys leads to excellent properties, but the metastable amorphous nature becomes an obstacle of the processing. This study introduces Water-Jet Guided Laser (WJGL) technology to process the Cu46Zr46Al8 amorphous alloy with improved surface morphology and minimal heat-affected zone. A noticeable heat-affected zone with thickness larger than 2 mm was observed in sample processed by conventional laser, while that of WJGL processing was less than 15 μm. The processing parameters of WJGL have no significant effect on the phases of the processed surface, only m-ZrO2, t-ZrO2, and Cu were determined. The processing surface morphology shows a strong dependence on the water pressure. Wave-like morphology formed in the processing surfaces under a water pressure of 30 MPa, which was invisible as the water pressure decreased to 10 MPa. Smaller water pressure together with lower laser power are beneficial to the surface quality, the minimum surface roughness of 0.8411 μm was obtained at the water pressure of 10 MPa and the laser power of 8 W. Finally, complex-shaped components were processed using WJGL, indicating that WJGL is a viable and effective alternative for machining amorphous alloys.
{"title":"Crystallization-resistant water-jet guided laser processing of Cu46Zr46Al8 amorphous alloy via thermally suppressed strategy","authors":"Hengming Hu , Caiyun Liu , Zihuai Su , Feng Ye , Bin Qian , Ye Dai , Shengzhi Sun , Binbin Liu , Jianrong Qiu","doi":"10.1016/j.intermet.2025.108789","DOIUrl":"10.1016/j.intermet.2025.108789","url":null,"abstract":"<div><div>The unique atomic packing of amorphous alloys leads to excellent properties, but the metastable amorphous nature becomes an obstacle of the processing. This study introduces Water-Jet Guided Laser (WJGL) technology to process the Cu<sub>46</sub>Zr<sub>46</sub>Al<sub>8</sub> amorphous alloy with improved surface morphology and minimal heat-affected zone. A noticeable heat-affected zone with thickness larger than 2 mm was observed in sample processed by conventional laser, while that of WJGL processing was less than 15 μm. The processing parameters of WJGL have no significant effect on the phases of the processed surface, only <em>m</em>-ZrO<sub>2</sub>, <em>t</em>-ZrO<sub>2</sub>, and Cu were determined. The processing surface morphology shows a strong dependence on the water pressure. Wave-like morphology formed in the processing surfaces under a water pressure of 30 MPa, which was invisible as the water pressure decreased to 10 MPa. Smaller water pressure together with lower laser power are beneficial to the surface quality, the minimum surface roughness of 0.8411 μm was obtained at the water pressure of 10 MPa and the laser power of 8 W. Finally, complex-shaped components were processed using WJGL, indicating that WJGL is a viable and effective alternative for machining amorphous alloys.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"182 ","pages":"Article 108789"},"PeriodicalIF":4.3,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143799060","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}
This study investigates the microstructure and martensitic transformation of (Ni50.3Ti49.7-yHfy)100-xNbx (x = 0, 5, 10 at. %; y = 10, 15, 20,25 at. %) alloys. The findings reveal that Nb addition significantly influences the alloy's microstructure. In Nb-containing alloys, β-Nb phase emerges alongside B19′ martensite and the Ti2Ni-type phase at room temperature. Notably, the β-Nb phase adopts a spherical morphology in the HfyNb5 alloys, whereas it becomes strip-shaped in the HfyNb10 alloys. Nb addition also affects key properties, leading to an increase in transformation temperature and transformation hysteresis, as well as enhancements in hardness, tensile strength, and elongation. Furthermore, increasing Hf content elevates the transformation temperature, attributed to a linear reduction in valence electron concentration (Cv), while also improving microhardness. These results provide critical insights into tailoring the properties of Ni-Ti-Hf-Nb alloys for advanced applications.
{"title":"Effects of Nb addition on the microstructure and martensitic transformation in NiTiHf-based high-temperature shape memory alloys","authors":"Bing Liu , Xiangjun Zhou , A.V. Shuitcev , Mehrdad Zarinejad , Yunxiang Tong","doi":"10.1016/j.intermet.2025.108790","DOIUrl":"10.1016/j.intermet.2025.108790","url":null,"abstract":"<div><div>This study investigates the microstructure and martensitic transformation of (Ni<sub>50.3</sub>Ti<sub>49.7-y</sub>Hf<sub>y</sub>)<sub>100-x</sub>Nb<sub>x</sub> (x = 0, 5, 10 at. %; y = 10, 15, 20,25 at. %) alloys. The findings reveal that Nb addition significantly influences the alloy's microstructure. In Nb-containing alloys, β-Nb phase emerges alongside B19′ martensite and the Ti<sub>2</sub>Ni-type phase at room temperature. Notably, the β-Nb phase adopts a spherical morphology in the Hf<sub>y</sub>Nb<sub>5</sub> alloys, whereas it becomes strip-shaped in the Hf<sub>y</sub>Nb<sub>10</sub> alloys. Nb addition also affects key properties, leading to an increase in transformation temperature and transformation hysteresis, as well as enhancements in hardness, tensile strength, and elongation. Furthermore, increasing Hf content elevates the transformation temperature, attributed to a linear reduction in valence electron concentration (<em>C</em><sub><em>v</em></sub>), while also improving microhardness. These results provide critical insights into tailoring the properties of Ni-Ti-Hf-Nb alloys for advanced applications.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"182 ","pages":"Article 108790"},"PeriodicalIF":4.3,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792239","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}
Although refractory high entropy alloys (RHEAs) have the potential to serve as nuclear materials, designing a high-performance alloy that can simultaneously endure extreme environments, such as elevated temperatures and radiation exposure, remains a significant challenge. In this work, elements with high melting points and low activation characteristics are selected to design Ti30V30Cr5Zr5Ta30-xWx (x = 5, 10, 15, 20 at.%) RHEAs that exhibit good high-temperature strength and irradiation resistance. The phase structure, mechanical properties, deformation mechanisms, and irradiation resistance of the RHEAs were investigated and discussed. All the low-activation Ti30V30Cr5Zr5Ta30-xWx RHEAs exhibited excellent phase stability. Typically, the Ti30V30Cr5Zr5Ta15W15 RHEA exhibited a yield strength, specific yield strength, and plasticity of 1607 MPa, 172.42 MPa·cm3/g and 22.7 % respectively at room temperature. At 800 °C and 1000 °C, it still had a yield strength of 851 MPa and 558 MPa respectively. The high strength of the Ti30V30Cr5Zr5Ta15W15 RHEA was attributed to the solid solution strengthening mechanism, in which the W element played an important role. The deformation mechanism of Ti30V30Cr5Zr5Ta15W15 RHEA at both room temperature and elevated temperatures was primarily governed by dislocation slip. Using low-energy and high-flux He ions, the irradiation resistance of the Ti30V30Cr5Zr5Ta20W10 and Ti30V30Cr5Zr5Ta15W15 RHEAs were also investigated. They demonstrated better radiation resistance surpassed that of pure W, showing remained flat surface and stable phase structure.
{"title":"Low activation Ti30V30Cr5Zr5Ta30-XWX refractory high entropy alloys with excellent mechanical properties and phase stability","authors":"Shunhua Chen , Yazhou Tang , Junsheng Zhang , Xiaokang Yue , Haidong Yang , Huohong Tang , Yucheng Wu","doi":"10.1016/j.intermet.2025.108780","DOIUrl":"10.1016/j.intermet.2025.108780","url":null,"abstract":"<div><div>Although refractory high entropy alloys (RHEAs) have the potential to serve as nuclear materials, designing a high-performance alloy that can simultaneously endure extreme environments, such as elevated temperatures and radiation exposure, remains a significant challenge. In this work, elements with high melting points and low activation characteristics are selected to design Ti<sub>30</sub>V<sub>30</sub>Cr<sub>5</sub>Zr<sub>5</sub>Ta<sub>30-x</sub>W<sub>x</sub> (x = 5, 10, 15, 20 at.%) RHEAs that exhibit good high-temperature strength and irradiation resistance. The phase structure, mechanical properties, deformation mechanisms, and irradiation resistance of the RHEAs were investigated and discussed. All the low-activation Ti<sub>30</sub>V<sub>30</sub>Cr<sub>5</sub>Zr<sub>5</sub>Ta<sub>30-x</sub>W<sub>x</sub> RHEAs exhibited excellent phase stability. Typically, the Ti<sub>30</sub>V<sub>30</sub>Cr<sub>5</sub>Zr<sub>5</sub>Ta<sub>15</sub>W<sub>15</sub> RHEA exhibited a yield strength, specific yield strength, and plasticity of 1607 MPa, 172.42 MPa·cm<sup>3</sup>/g and 22.7 % respectively at room temperature. At 800 °C and 1000 °C, it still had a yield strength of 851 MPa and 558 MPa respectively. The high strength of the Ti<sub>30</sub>V<sub>30</sub>Cr<sub>5</sub>Zr<sub>5</sub>Ta<sub>15</sub>W<sub>15</sub> RHEA was attributed to the solid solution strengthening mechanism, in which the W element played an important role. The deformation mechanism of Ti<sub>30</sub>V<sub>30</sub>Cr<sub>5</sub>Zr<sub>5</sub>Ta<sub>15</sub>W<sub>15</sub> RHEA at both room temperature and elevated temperatures was primarily governed by dislocation slip. Using low-energy and high-flux He ions, the irradiation resistance of the Ti<sub>30</sub>V<sub>30</sub>Cr<sub>5</sub>Zr<sub>5</sub>Ta<sub>20</sub>W<sub>10</sub> and Ti<sub>30</sub>V<sub>30</sub>Cr<sub>5</sub>Zr<sub>5</sub>Ta<sub>15</sub>W<sub>15</sub> RHEAs were also investigated. They demonstrated better radiation resistance surpassed that of pure W, showing remained flat surface and stable phase structure.</div></div>","PeriodicalId":331,"journal":{"name":"Intermetallics","volume":"182 ","pages":"Article 108780"},"PeriodicalIF":4.3,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143792241","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}
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