Pub Date : 2024-07-18DOI: 10.1016/j.jmrt.2024.07.106
Jinle Luo, Haojie Lu, Ming Wen, Shengguo Ma, Xizhang Chen
Powder Plasma Arc Additive Manufacturing (PPA-AM) technique has tremendous potential for the practical application in medium-entropy alloys (MEAs). In this study, we investigated the effect of heat treatment on microstructural evolution, mechanical properties, and the work hardening behavior in the PPA-AM processed (CoCrNi)AlTi MEA. The results show that the As-built specimen is a single-phase FCC structure, displaying <001> strong FCC texture in the deposition direction. The stacking faults (SFs) and dislocations were observed in the alloy, which formed the stacking fault networks and the Lomer-Cottrell locks structure. The plasticity of the alloy increased significantly after the high-temperature heat treatment, which can be attributed to the modifications of the microstructure, such as the weakening of the texture strength and the reduction of the stresses. Low-temperature heat treatment decreases the density of dislocations in the alloy, but promotes the generation of the co-lattice phase. The evolution of the dislocation density, texture strength, and precipitates significantly influenced the strain hardening behavior and mechanical properties. The tensile results showed that the strength and plasticity of the samples were increased after two-step heat treatment. The yield strength, ultimate tensile strength, and elongation to failure were 733 MPa, 1080 MPa, and 22.3%, respectively, which were 16.2%, 20.3%, and 15.5% higher than the As-built samples. This work elucidates the underlying mechanisms of heat treatment on the microstructure and mechanical properties of the alloy.
{"title":"Exceptional strength-ductility synergy in additively manufactured (CoCrNi)90Al5Ti5 medium-entropy alloy by heat treatment","authors":"Jinle Luo, Haojie Lu, Ming Wen, Shengguo Ma, Xizhang Chen","doi":"10.1016/j.jmrt.2024.07.106","DOIUrl":"https://doi.org/10.1016/j.jmrt.2024.07.106","url":null,"abstract":"Powder Plasma Arc Additive Manufacturing (PPA-AM) technique has tremendous potential for the practical application in medium-entropy alloys (MEAs). In this study, we investigated the effect of heat treatment on microstructural evolution, mechanical properties, and the work hardening behavior in the PPA-AM processed (CoCrNi)AlTi MEA. The results show that the As-built specimen is a single-phase FCC structure, displaying <001> strong FCC texture in the deposition direction. The stacking faults (SFs) and dislocations were observed in the alloy, which formed the stacking fault networks and the Lomer-Cottrell locks structure. The plasticity of the alloy increased significantly after the high-temperature heat treatment, which can be attributed to the modifications of the microstructure, such as the weakening of the texture strength and the reduction of the stresses. Low-temperature heat treatment decreases the density of dislocations in the alloy, but promotes the generation of the co-lattice phase. The evolution of the dislocation density, texture strength, and precipitates significantly influenced the strain hardening behavior and mechanical properties. The tensile results showed that the strength and plasticity of the samples were increased after two-step heat treatment. The yield strength, ultimate tensile strength, and elongation to failure were 733 MPa, 1080 MPa, and 22.3%, respectively, which were 16.2%, 20.3%, and 15.5% higher than the As-built samples. This work elucidates the underlying mechanisms of heat treatment on the microstructure and mechanical properties of the alloy.","PeriodicalId":501120,"journal":{"name":"Journal of Materials Research and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141783628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-18DOI: 10.1016/j.jmrt.2024.07.104
Jiaxin Zhang, Shengguo Ma, Xiaoxiao Liu, Junwei Qiao, Jianjun Wang, Dan Zhao, Zhiming Jiao, Tuanwei Zhang, Bin Xu, Zhihua Wang
A Co-free non-equiatomic NiCrFeAlTi medium-entropy alloy (MEA) with an excellent strength-ductility synergy was fabricated, which shows a multiphase structure composed of face-centered cubic (FCC), L1 (ordered FCC), and Cr-rich body-centered cubic (BCC) phase by thermomechanical processing. Specifically, the aged sample displays the outstanding yield tensile strength (YTS, ∼1188 MPa), ultimate tensile strength (UTS, ∼1560 MPa) and work-hardening rate (WHR, ∼4.5 GPa) values as well as an acceptable plasticity of ∼16.6%. Theoretical calculations suggest that precipitation strengthening significantly contributes to achieving the fascinating tensile strength among various strengthening contributors. Further analyses reveal that multiple nanoscale stacking-fault (SF) networks are activated during plastic deformation in the aged alloy. Accordingly, the dual effects consisting of the hierarchical precipitation structure and SF networks lead to the combination of excellent tensile strength and strain-hardening capacity.
通过热机械加工，制备了一种无钴非等原子镍铬铁铝钛中熵合金（MEA），该合金具有优异的强度-电导率协同效应，呈现出由面心立方（FCC）、L1（有序 FCC）和富铬体心立方（BCC）相组成的多相结构。具体而言，老化样品显示出优异的屈服拉伸强度（YTS，∼1188 兆帕）、极限拉伸强度（UTS，∼1560 兆帕）和加工硬化率（WHR，∼4.5 GPa）值，以及可接受的塑性（∼16.6%）。理论计算表明，在各种强化因素中，沉淀强化对达到令人着迷的抗拉强度有显著贡献。进一步的分析表明，在老化合金的塑性变形过程中，多个纳米级堆叠断层（SF）网络被激活。因此，由分层沉淀结构和 SF 网络组成的双重效应导致了优异的抗拉强度和应变硬化能力。
{"title":"An excellent combination of strength and ductility via hierarchical precipitation structures in Co-free medium-entropy alloys","authors":"Jiaxin Zhang, Shengguo Ma, Xiaoxiao Liu, Junwei Qiao, Jianjun Wang, Dan Zhao, Zhiming Jiao, Tuanwei Zhang, Bin Xu, Zhihua Wang","doi":"10.1016/j.jmrt.2024.07.104","DOIUrl":"https://doi.org/10.1016/j.jmrt.2024.07.104","url":null,"abstract":"A Co-free non-equiatomic NiCrFeAlTi medium-entropy alloy (MEA) with an excellent strength-ductility synergy was fabricated, which shows a multiphase structure composed of face-centered cubic (FCC), L1 (ordered FCC), and Cr-rich body-centered cubic (BCC) phase by thermomechanical processing. Specifically, the aged sample displays the outstanding yield tensile strength (YTS, ∼1188 MPa), ultimate tensile strength (UTS, ∼1560 MPa) and work-hardening rate (WHR, ∼4.5 GPa) values as well as an acceptable plasticity of ∼16.6%. Theoretical calculations suggest that precipitation strengthening significantly contributes to achieving the fascinating tensile strength among various strengthening contributors. Further analyses reveal that multiple nanoscale stacking-fault (SF) networks are activated during plastic deformation in the aged alloy. Accordingly, the dual effects consisting of the hierarchical precipitation structure and SF networks lead to the combination of excellent tensile strength and strain-hardening capacity.","PeriodicalId":501120,"journal":{"name":"Journal of Materials Research and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141783629","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
High entropy alloy (HEA) coatings of FeCoCrNiNbMo was prepared on 304 stainless steel using laser cladding and subsequently remelted multiple times. The effects of multiple thermal cycles on the phase composition, grain size, microstructure evolution, and corrosion resistance of the coatings are thoroughly investigated. The original coating consisted of face-centered cubic (FCC), Laves, and NbC phases, and the phase composition does not change obviously, but the distribution and microstructure of the phase change significantly after multiple remelting. As the number of remelting times increased, the bar-like eutectic structure decreased while the lamellar eutectic structure became more prominent. Laser remelting induced dynamic recrystallization in the coating, resulting in a transformation from columnar grains to equiaxed grains, and then back to columnar grains. The grain size also changes significantly with different remelting times. Potentiodynamic polarization and electrochemical impact spectroscopy measurements were conducted in a 3.5 wt% NaCl solution to evaluate the corrosion resistance of the coating. The results revealed both the original coating and the once-remelted coating exhibited lower corrosion current density and higher corrosion potential, but the latter had a higher Faraday impedance. Additionally, immersion tests were performed in 10 wt% FeCl solution, which demonstrated that the once-remelted coating displayed fine and uniform corrosion pits with shallow depth. This study provides theoretical support for the regulation of microstructure and the optimization of coating performance. Furthermore, the microstructure evolution law discovered in this research is also applicable to additive manufacturing.
{"title":"Effect of multiple laser remelting on microstructure and corrosion resistance of Fe0.5CoCrNi1.5Nb0.68Mo0.3 high entropy alloy coatings","authors":"Yongfeng Li, Lixia Wang, Jian Zhang, Meiqin Liu, Shenggang Guo, Jing Liu, Lili Cao","doi":"10.1016/j.jmrt.2024.07.114","DOIUrl":"https://doi.org/10.1016/j.jmrt.2024.07.114","url":null,"abstract":"High entropy alloy (HEA) coatings of FeCoCrNiNbMo was prepared on 304 stainless steel using laser cladding and subsequently remelted multiple times. The effects of multiple thermal cycles on the phase composition, grain size, microstructure evolution, and corrosion resistance of the coatings are thoroughly investigated. The original coating consisted of face-centered cubic (FCC), Laves, and NbC phases, and the phase composition does not change obviously, but the distribution and microstructure of the phase change significantly after multiple remelting. As the number of remelting times increased, the bar-like eutectic structure decreased while the lamellar eutectic structure became more prominent. Laser remelting induced dynamic recrystallization in the coating, resulting in a transformation from columnar grains to equiaxed grains, and then back to columnar grains. The grain size also changes significantly with different remelting times. Potentiodynamic polarization and electrochemical impact spectroscopy measurements were conducted in a 3.5 wt% NaCl solution to evaluate the corrosion resistance of the coating. The results revealed both the original coating and the once-remelted coating exhibited lower corrosion current density and higher corrosion potential, but the latter had a higher Faraday impedance. Additionally, immersion tests were performed in 10 wt% FeCl solution, which demonstrated that the once-remelted coating displayed fine and uniform corrosion pits with shallow depth. This study provides theoretical support for the regulation of microstructure and the optimization of coating performance. Furthermore, the microstructure evolution law discovered in this research is also applicable to additive manufacturing.","PeriodicalId":501120,"journal":{"name":"Journal of Materials Research and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141783814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-18DOI: 10.1016/j.jmrt.2024.07.103
Hyeon-Woo Son, Sung-Ho Kang, Kwangjun Euh, Yun-Soo Lee, Kyoungdoc Kim
This study investigates the effect of minor Li addition on the solute clustering and thermal stability of precipitates in artificially aged Al–Mg–Si–Cu (AA6061) alloys. Li addition hinders the initial changes in hardness and electrical conductivity by delaying solute clustering during early aging. The delay in cluster formation is attributed to the disturbance of Mg enrichment by the formation of Si–Li clusters, unlike the Sn element with vacancy-trapping effect. Additionally, Li addition is found to coarsen the precipitates during over aging, thereby reducing the thermal stability of the Al–Mg–Si–Cu alloy. Gibbsian interfacial excess calculations of the Li solute indicate that the low coarsening resistance of the Li-containing precipitate is mainly caused by the small amount of equilibrium Li segregation at the internal interface between the matrix and over-aged precipitate. A decrease in the number of nucleation sites, originating from the suppression of cluster formation in the early-aging stage, is also suggested as a reason for the coarse precipitate structure. Finally, despite the high solubility of Li into precipitates, Li addition does not disorder or change the crystal structure of the precipitates. It simply increases the volume of the precipitate by an amount equivalent to or greater than the added Li, without increasing the thermal stability.
{"title":"Effect of Li addition on the precipitation behavior of AA6061 alloy","authors":"Hyeon-Woo Son, Sung-Ho Kang, Kwangjun Euh, Yun-Soo Lee, Kyoungdoc Kim","doi":"10.1016/j.jmrt.2024.07.103","DOIUrl":"https://doi.org/10.1016/j.jmrt.2024.07.103","url":null,"abstract":"This study investigates the effect of minor Li addition on the solute clustering and thermal stability of precipitates in artificially aged Al–Mg–Si–Cu (AA6061) alloys. Li addition hinders the initial changes in hardness and electrical conductivity by delaying solute clustering during early aging. The delay in cluster formation is attributed to the disturbance of Mg enrichment by the formation of Si–Li clusters, unlike the Sn element with vacancy-trapping effect. Additionally, Li addition is found to coarsen the precipitates during over aging, thereby reducing the thermal stability of the Al–Mg–Si–Cu alloy. Gibbsian interfacial excess calculations of the Li solute indicate that the low coarsening resistance of the Li-containing precipitate is mainly caused by the small amount of equilibrium Li segregation at the internal interface between the matrix and over-aged precipitate. A decrease in the number of nucleation sites, originating from the suppression of cluster formation in the early-aging stage, is also suggested as a reason for the coarse precipitate structure. Finally, despite the high solubility of Li into precipitates, Li addition does not disorder or change the crystal structure of the precipitates. It simply increases the volume of the precipitate by an amount equivalent to or greater than the added Li, without increasing the thermal stability.","PeriodicalId":501120,"journal":{"name":"Journal of Materials Research and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141783630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-18DOI: 10.1016/j.jmrt.2024.07.115
Cheng Yao, Min Wang, Youjin Ni, Jian Gong, Zeyu Yang, Lidong Xing, Yanping Bao
In this study, the spray characteristics of the cooling water flux of the traditional single nozzle and novel dual nozzle were innovatively and effectively incorporated into a 3D/2D flow-temperature-concentration segmented model. The model was used to investigate the effects of spray characteristics on the flow, heat distribution, solute transport, solidified shell, and mushy zone of steel in the continuous casting. The results showed that various flow patterns of liquid steel in the turbulent zone significantly affected the temperature and carbon concentration distribution. Until Zone 7, the cooling water fluxes in the six cases remained unchanged. The peak temperatures of cases 1 and 4 in Zone 7 were 1253.11 and 1273.51 K, respectively, indicating that the spray characteristic was the primary cause of the variations in slab surface temperatures. The cooling water fluxes in the six cases change from Zone 8 onward. The six cases had differences of −21.39, 17.87, 46.95, −22.08, 16.86, and 45.68 K between the initial and final temperatures in Zone 8, respectively, meeting the requirement of keeping the maximum temperature recovery rate of slab surface under 100 °C/m. However, the final temperatures for cases 2, 3, and 6 were 1225.62, 1196.50, and 1218.91 K, respectively. These temperatures fall within a realistic plastic temperature range, which must be higher than 1220 K. As a result, the plastic cracking in the slab was possible. The maximum temperature gradient differences of the six cases between feature lines at the end of Zone 8 were 0.793, 0.814, 0.829, 0.185, 0.179, and 0.179 K/mm. These results showed that the optimization effect on the temperature gradient difference was insignificant as the cooling intensity rose. However, the carbon concentration uniformity was marginally improved by increasing the cooling water flux. Finally, a state-owned steel company in China chose case 5 (dual nozzle with moderate cooling intensity at the slab solidified end) as the optimum option for the slab continuous casting caster. The dual nozzle enhanced and promoted the efficient and homogeneous production of the metallurgical process.
{"title":"Numerical study on the effect of high efficient cooling nozzles and varying cooling intensity on metallurgical transport behaviors during the slab continuous casting","authors":"Cheng Yao, Min Wang, Youjin Ni, Jian Gong, Zeyu Yang, Lidong Xing, Yanping Bao","doi":"10.1016/j.jmrt.2024.07.115","DOIUrl":"https://doi.org/10.1016/j.jmrt.2024.07.115","url":null,"abstract":"In this study, the spray characteristics of the cooling water flux of the traditional single nozzle and novel dual nozzle were innovatively and effectively incorporated into a 3D/2D flow-temperature-concentration segmented model. The model was used to investigate the effects of spray characteristics on the flow, heat distribution, solute transport, solidified shell, and mushy zone of steel in the continuous casting. The results showed that various flow patterns of liquid steel in the turbulent zone significantly affected the temperature and carbon concentration distribution. Until Zone 7, the cooling water fluxes in the six cases remained unchanged. The peak temperatures of cases 1 and 4 in Zone 7 were 1253.11 and 1273.51 K, respectively, indicating that the spray characteristic was the primary cause of the variations in slab surface temperatures. The cooling water fluxes in the six cases change from Zone 8 onward. The six cases had differences of −21.39, 17.87, 46.95, −22.08, 16.86, and 45.68 K between the initial and final temperatures in Zone 8, respectively, meeting the requirement of keeping the maximum temperature recovery rate of slab surface under 100 °C/m. However, the final temperatures for cases 2, 3, and 6 were 1225.62, 1196.50, and 1218.91 K, respectively. These temperatures fall within a realistic plastic temperature range, which must be higher than 1220 K. As a result, the plastic cracking in the slab was possible. The maximum temperature gradient differences of the six cases between feature lines at the end of Zone 8 were 0.793, 0.814, 0.829, 0.185, 0.179, and 0.179 K/mm. These results showed that the optimization effect on the temperature gradient difference was insignificant as the cooling intensity rose. However, the carbon concentration uniformity was marginally improved by increasing the cooling water flux. Finally, a state-owned steel company in China chose case 5 (dual nozzle with moderate cooling intensity at the slab solidified end) as the optimum option for the slab continuous casting caster. The dual nozzle enhanced and promoted the efficient and homogeneous production of the metallurgical process.","PeriodicalId":501120,"journal":{"name":"Journal of Materials Research and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141783626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-18DOI: 10.1016/j.jmrt.2024.07.101
Yongyong Jia, Zhihui Cai, Mingwei Yuan, Shangkun Wang, Lifeng Ma
The effect of shot peening treatment on dry sliding wear behavior of medium manganese steel in as-hot rolled and solution-aging states were studied. The results show that before shot peening, the wear resistance of the solution-aging sample was better than that of hot-rolled steel. The excellent wear resistance was due to the synergistic effect of Ti (C, N) particle precipitation strengthening and grain refinement in the matrix, resulting in high strain hardening ability. After shot peening, different microscopic evolution mechanisms caused great contrast in properties. The as-hot rolled sample released internal stress by generating deformation twins (DTs) during shot peening. With the increased shot peening time, the DTs thickened and interacted with dislocations, effectively reducing the free dislocation path, releasing residual stress, and significantly improving wear resistance. However, solution-aging steel generated many dislocations, resulting in residual stress concentration at Ti (C, N) particles, promoting crack initiation and propagation, and deteriorated wear resistance.
{"title":"Influence of shot-peening treatment on wear resistance of medium manganese steel","authors":"Yongyong Jia, Zhihui Cai, Mingwei Yuan, Shangkun Wang, Lifeng Ma","doi":"10.1016/j.jmrt.2024.07.101","DOIUrl":"https://doi.org/10.1016/j.jmrt.2024.07.101","url":null,"abstract":"The effect of shot peening treatment on dry sliding wear behavior of medium manganese steel in as-hot rolled and solution-aging states were studied. The results show that before shot peening, the wear resistance of the solution-aging sample was better than that of hot-rolled steel. The excellent wear resistance was due to the synergistic effect of Ti (C, N) particle precipitation strengthening and grain refinement in the matrix, resulting in high strain hardening ability. After shot peening, different microscopic evolution mechanisms caused great contrast in properties. The as-hot rolled sample released internal stress by generating deformation twins (DTs) during shot peening. With the increased shot peening time, the DTs thickened and interacted with dislocations, effectively reducing the free dislocation path, releasing residual stress, and significantly improving wear resistance. However, solution-aging steel generated many dislocations, resulting in residual stress concentration at Ti (C, N) particles, promoting crack initiation and propagation, and deteriorated wear resistance.","PeriodicalId":501120,"journal":{"name":"Journal of Materials Research and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141783631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sn–Bi based solders are used in electronic packaging for interconnection processes. However, the rate of research on the comprehensive performance of solders is difficult to match the rapid development of advanced manufacturing of integrated circuits, resulting in the inability to obtain interconnect structures with excellent reliability for electronic devices. To demand a more effective modification method, we chose to dope 1.0 wt % In element in Sn58Bi–1Sb alloy. The strength, micromechanical properties and creep resistance of the solder were improved due to the combined effect of solid solution strengthening and diffusely distributed second phase strengthening. Furthermore, the addition of In element dramatically improved the thermal properties and wettability due to the generation of BiIn intermetallic compounds (88.9 °C) and the activation energy of the solder wettability reaction was reduced to 247.36 J/mol. Notably, the addition of In element increased the amount of β-Sn phase deviation and decreased the Schmid factor value of β-Sn phase, resulting in a significant increase in the strength and micro-zone creep resistance. Under the action of current, a large amount of uniform Bi particle deviations and sub-crystalline structures persist in the β-Sn phase of the Sn58Bi–1Sb1In solder matrix. In the Cu/Sn58Bi–1Sb1In/Cu joints, many Bi particles are staggered in the β-Sn phase. Since the resistivity of the β-Sn phase is smaller than that of the Bi phase, the energization process leads to a possible further increase of the local currents at certain locations in the β-Sn phase, which reduces the electromigration resistance of the β-Sn phase. After energization, the biphasic twin structure with excellent electromigration resistance starts to degrade. The results show that the doping of In element comprehensively improves the performance of Sn58Bi–1Sb solder. It opens up a new idea for the design of alloying modification of tin-bismuth based solder.
{"title":"Mechanical properties and microstructure evolution of Sn–Bi-based solder joints by microalloying regulation mechanism","authors":"Xuefeng Wu, Zhuangzhuang Hou, Xiaochen Xie, Pengrong Lin, Yongjun Huo, Yong Wang, Xiuchen Zhao","doi":"10.1016/j.jmrt.2024.07.076","DOIUrl":"https://doi.org/10.1016/j.jmrt.2024.07.076","url":null,"abstract":"Sn–Bi based solders are used in electronic packaging for interconnection processes. However, the rate of research on the comprehensive performance of solders is difficult to match the rapid development of advanced manufacturing of integrated circuits, resulting in the inability to obtain interconnect structures with excellent reliability for electronic devices. To demand a more effective modification method, we chose to dope 1.0 wt % In element in Sn58Bi–1Sb alloy. The strength, micromechanical properties and creep resistance of the solder were improved due to the combined effect of solid solution strengthening and diffusely distributed second phase strengthening. Furthermore, the addition of In element dramatically improved the thermal properties and wettability due to the generation of BiIn intermetallic compounds (88.9 °C) and the activation energy of the solder wettability reaction was reduced to 247.36 J/mol. Notably, the addition of In element increased the amount of β-Sn phase deviation and decreased the Schmid factor value of β-Sn phase, resulting in a significant increase in the strength and micro-zone creep resistance. Under the action of current, a large amount of uniform Bi particle deviations and sub-crystalline structures persist in the β-Sn phase of the Sn58Bi–1Sb1In solder matrix. In the Cu/Sn58Bi–1Sb1In/Cu joints, many Bi particles are staggered in the β-Sn phase. Since the resistivity of the β-Sn phase is smaller than that of the Bi phase, the energization process leads to a possible further increase of the local currents at certain locations in the β-Sn phase, which reduces the electromigration resistance of the β-Sn phase. After energization, the biphasic twin structure with excellent electromigration resistance starts to degrade. The results show that the doping of In element comprehensively improves the performance of Sn58Bi–1Sb solder. It opens up a new idea for the design of alloying modification of tin-bismuth based solder.","PeriodicalId":501120,"journal":{"name":"Journal of Materials Research and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141718577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Based on the microstructure analysis, the present research investigated the influence of various austenitizing conditions on the transformation behavior of intermetallic compound particles, i.e. η-NiTi, and the reversed austenite during ageing treatment in Ti–Mo maraging stainless steel, as well as the related mechanical properties. The results revealed numerous tiny rod-like intermetallic compound particles, i.e. η-NiTi, having a Burgers orientation relationship, i.e., // ; //, with the martensite matrix, as well as blocky, lath, and granular reversed austenite of various sizes distributed within the tempered martensite matrix. Regardless of the austenitizing treatment condition, more reversed austenite was found in the samples aged at 520 °C than in those aged at 640 °C. Although this finding was not consistent with the Thermo-Calc predictions, it should be associated with the thermal stability of reversed austenite at different ageing temperatures. In other words, the greater amount of reversed austenite that formed at 640 °C did not remain at room temperature due to secondary martensite transformation during cooling, as was verified by EBSD analysis.
{"title":"Exploring the effects of austenitizing conditions on the heterogeneous microstructure and mechanical properties of 11Cr–11Ni–Ti–Mo maraging stainless steel: Breakthrough in the strength-ductility trade-off","authors":"Chih-Yuan Chen, Iting Chiang, Po-Han Chiu, Tzu-Ching Tsao, Yo-Lun Yang, Yung-Chang Kang","doi":"10.1016/j.jmrt.2024.07.039","DOIUrl":"https://doi.org/10.1016/j.jmrt.2024.07.039","url":null,"abstract":"Based on the microstructure analysis, the present research investigated the influence of various austenitizing conditions on the transformation behavior of intermetallic compound particles, i.e. η-NiTi, and the reversed austenite during ageing treatment in Ti–Mo maraging stainless steel, as well as the related mechanical properties. The results revealed numerous tiny rod-like intermetallic compound particles, i.e. η-NiTi, having a Burgers orientation relationship, i.e., // ; //, with the martensite matrix, as well as blocky, lath, and granular reversed austenite of various sizes distributed within the tempered martensite matrix. Regardless of the austenitizing treatment condition, more reversed austenite was found in the samples aged at 520 °C than in those aged at 640 °C. Although this finding was not consistent with the Thermo-Calc predictions, it should be associated with the thermal stability of reversed austenite at different ageing temperatures. In other words, the greater amount of reversed austenite that formed at 640 °C did not remain at room temperature due to secondary martensite transformation during cooling, as was verified by EBSD analysis.","PeriodicalId":501120,"journal":{"name":"Journal of Materials Research and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141718518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-08DOI: 10.1016/j.jmrt.2024.07.020
Yuanyuan Qiao, Taikun Hao, Yanqing Lai, Hongwei Liang, Ning Zhao
Sn–Ag solders are widely used for advanced electronic packaging. The combined effect of Ag element and temperature gradient (TG) on the formation of Sn grains in Cu/Sn-Ag/Cu micro solder joints was elucidated systematically. Numerous small-sized β-Sn grains were formed in both Cu/Sn/Cu and Cu/Sn-0.5Ag/Cu micro solder joints after reflow with or without TG. The Cu/Sn-0.5Ag/Cu joint was found to have more twinning β-Sn structures. The formation of the multiple β-Sn grains in these two joints was attributed to the presence of multiple tetrahedral metastable short-range order (SRO) structures which acted as nuclei for the nucleation and growth of β-Sn. The existence of TG slightly enhanced the preferred orientation characteristics of Sn grains. For the joints with Ag content was or higher than 2 wt%, several Sn grains were formed without TG, while a single or highly oriented Sn grains were observed with TG. The number and orientation of Sn grains were affected by the combined effect of Ag element and TG significantly. The β-Sn grains formed without TG were based on the {101} type cyclic twinning configuration clusters that stabilized by Ag atoms and acted as nuclei. The formation of a single or highly preferred β-Sn grains was benefit from the combined effect of Ag element and TG. The results provide theoretical guidance for optimizing the composition of Sn–Ag solders and controlling the microstructure of the joints, thereby contributing to the advancement of electronic packaging technologies.
{"title":"Combined effect of Ag element and temperature gradient on the formation of highly orientated Sn grains in micro solder joints","authors":"Yuanyuan Qiao, Taikun Hao, Yanqing Lai, Hongwei Liang, Ning Zhao","doi":"10.1016/j.jmrt.2024.07.020","DOIUrl":"https://doi.org/10.1016/j.jmrt.2024.07.020","url":null,"abstract":"Sn–Ag solders are widely used for advanced electronic packaging. The combined effect of Ag element and temperature gradient (TG) on the formation of Sn grains in Cu/Sn-Ag/Cu micro solder joints was elucidated systematically. Numerous small-sized β-Sn grains were formed in both Cu/Sn/Cu and Cu/Sn-0.5Ag/Cu micro solder joints after reflow with or without TG. The Cu/Sn-0.5Ag/Cu joint was found to have more twinning β-Sn structures. The formation of the multiple β-Sn grains in these two joints was attributed to the presence of multiple tetrahedral metastable short-range order (SRO) structures which acted as nuclei for the nucleation and growth of β-Sn. The existence of TG slightly enhanced the preferred orientation characteristics of Sn grains. For the joints with Ag content was or higher than 2 wt%, several Sn grains were formed without TG, while a single or highly oriented Sn grains were observed with TG. The number and orientation of Sn grains were affected by the combined effect of Ag element and TG significantly. The β-Sn grains formed without TG were based on the {101} type cyclic twinning configuration clusters that stabilized by Ag atoms and acted as nuclei. The formation of a single or highly preferred β-Sn grains was benefit from the combined effect of Ag element and TG. The results provide theoretical guidance for optimizing the composition of Sn–Ag solders and controlling the microstructure of the joints, thereby contributing to the advancement of electronic packaging technologies.","PeriodicalId":501120,"journal":{"name":"Journal of Materials Research and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141718516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
TiAl composite with core-shell structure was in-situ synthesized incorporating BN nanosheets and graphene oxide into TiAl alloy using SPS, and the hot deformation behaviors were subsequently investigated on a Gleeble-1500D thermal simulation machine. The microstructural evolution and the influence of ceramic particles on hot deformation were revealed using OM, SEM, TEM, and EBSD. The results demonstrated a refined microstructure of TiAl composite induced by ceramic particles providing extra nucleation sites for DRX, contributing to lower flow stress, with peak stresses of 387 and 360 MPa for TiAl alloy and TiAl composite deformed at 1200 °C/1s, respectively. Moreover, dislocation slip was inhibited by ceramic particles leading to dislocation pile-up, facilitating the nucleation and growth of DRX at lamellar colony boundaries and α/γ interfaces. Notably, the “shell” composed of TiB and TiAlN nanoparticles coordinated the deformation of lamellar colonies with different orientations, improving the hot workability of TiAl composite.
利用 SPS 原位合成了具有核壳结构的 TiAl 复合材料，并在 TiAl 合金中加入了 BN 纳米片和氧化石墨烯，随后在 Gleeble-1500D 热模拟机上研究了热变形行为。利用光学显微镜、扫描电镜、电子显微镜和 EBSD 揭示了微观结构的演变以及陶瓷颗粒对热变形的影响。结果表明，由于陶瓷颗粒为 DRX 提供了额外的成核点，TiAl 复合材料的微观结构得到了细化，从而降低了流动应力，在 1200 °C/1s 下变形的 TiAl 合金和 TiAl 复合材料的峰值应力分别为 387 和 360 MPa。此外，陶瓷颗粒抑制了位错滑移，导致位错堆积，促进了 DRX 在片状菌落边界和 α/γ 界面的成核和生长。值得注意的是，由 TiB 和 TiAlN 纳米粒子组成的 "壳 "协调了不同取向的片状菌落的变形，改善了 TiAl 复合材料的热加工性能。
{"title":"Improved hot workability of TiAl composite with core-shell structure via in-situ synthesized multi-phases ceramic particles","authors":"Siying Li, Yupeng Wang, Tengfei Ma, Xiaohong Wang, Duo Dong, Dongdong Zhu, Hongze Fang, Ruirun Chen","doi":"10.1016/j.jmrt.2024.07.031","DOIUrl":"https://doi.org/10.1016/j.jmrt.2024.07.031","url":null,"abstract":"TiAl composite with core-shell structure was in-situ synthesized incorporating BN nanosheets and graphene oxide into TiAl alloy using SPS, and the hot deformation behaviors were subsequently investigated on a Gleeble-1500D thermal simulation machine. The microstructural evolution and the influence of ceramic particles on hot deformation were revealed using OM, SEM, TEM, and EBSD. The results demonstrated a refined microstructure of TiAl composite induced by ceramic particles providing extra nucleation sites for DRX, contributing to lower flow stress, with peak stresses of 387 and 360 MPa for TiAl alloy and TiAl composite deformed at 1200 °C/1s, respectively. Moreover, dislocation slip was inhibited by ceramic particles leading to dislocation pile-up, facilitating the nucleation and growth of DRX at lamellar colony boundaries and α/γ interfaces. Notably, the “shell” composed of TiB and TiAlN nanoparticles coordinated the deformation of lamellar colonies with different orientations, improving the hot workability of TiAl composite.","PeriodicalId":501120,"journal":{"name":"Journal of Materials Research and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141585821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：