Pub Date : 2025-01-22DOI: 10.1007/s12540-024-01878-4
Georgii Khartcyzov, Maksym Shevchenko, Evgenii Nekhoroshev, Evgueni Jak
The present study focused on phase equilibria in the PbO–AlO1.5 and PbO–AlO1.5–SiO2 systems. The equilibration and quenching technique followed by the electron probe X-ray microanalysis (EPMA) was used in the present study. The liquidus of the PbO–AlO1.5–SiO2 system in air, including corundum (Al2O3), cristobalite/tridymite/quartz (SiO2), feldspar (PbAl2Si2+xO8+2x), massicot (PbO), mullite (Al6+2xSi2−2xO13−x), PbAl12O19, PbAl2O4, Pb9Al8O21, Pb6Al2Si6O21, Pb4Al2Si2O11, Pb4Al4Si3O16, Pb3Al10SiO20 and Pb12Al2Si20O55 primary phase fields, has been characterised. New lead aluminosilicate compounds, Pb13Al4Si6O31, Pb12Al6Si10O31, Pb9Al4Si8O31, Pb7Al2Si8O26 and Pb7Al2Si10O30 were found to coexist with oxide liquid. The PbO–AlO1.5 binary and PbO–AlO1.5–SiO2 ternary systems in air were reoptimized based on the obtained experimental data. New experimental results together with phase equilibria and thermodynamic literature data were used to obtain a self-consistent set of parameters of the thermodynamic model for all phases of the PbO–AlO1.5–SiO2 system in air. The predicted liquidus projection of the PbO–AlO1.5–SiO2 system was presented for the first time in the full range of temperatures and compositions.
{"title":"Integrated Experimental and Thermodynamic Modelling Study of Phase Equilibria in the PbO-AlO1.5-SiO2 System in Air","authors":"Georgii Khartcyzov, Maksym Shevchenko, Evgenii Nekhoroshev, Evgueni Jak","doi":"10.1007/s12540-024-01878-4","DOIUrl":"10.1007/s12540-024-01878-4","url":null,"abstract":"<div><p>The present study focused on phase equilibria in the PbO–AlO<sub>1.5</sub> and PbO–AlO<sub>1.5</sub>–SiO<sub>2</sub> systems. The equilibration and quenching technique followed by the electron probe X-ray microanalysis (EPMA) was used in the present study. The liquidus of the PbO–AlO<sub>1.5</sub>–SiO<sub>2</sub> system in air, including corundum (Al<sub>2</sub>O<sub>3</sub>), cristobalite/tridymite/quartz (SiO<sub>2</sub>), feldspar (PbAl<sub>2</sub>Si<sub>2+<i>x</i></sub>O<sub>8+2<i>x</i></sub>), massicot (PbO), mullite (Al<sub>6+2<i>x</i></sub>Si<sub>2−2<i>x</i></sub>O<sub>13−<i>x</i></sub>), PbAl<sub>12</sub>O<sub>19</sub>, PbAl<sub>2</sub>O<sub>4</sub>, Pb<sub>9</sub>Al<sub>8</sub>O<sub>21</sub>, Pb<sub>6</sub>Al<sub>2</sub>Si<sub>6</sub>O<sub>21</sub>, Pb<sub>4</sub>Al<sub>2</sub>Si<sub>2</sub>O<sub>11</sub>, Pb<sub>4</sub>Al<sub>4</sub>Si<sub>3</sub>O<sub>16</sub>, Pb<sub>3</sub>Al<sub>10</sub>SiO<sub>20</sub> and Pb<sub>12</sub>Al<sub>2</sub>Si<sub>20</sub>O<sub>55</sub> primary phase fields, has been characterised. New lead aluminosilicate compounds, Pb<sub>13</sub>Al<sub>4</sub>Si<sub>6</sub>O<sub>31</sub>, Pb<sub>12</sub>Al<sub>6</sub>Si<sub>10</sub>O<sub>31</sub>, Pb<sub>9</sub>Al<sub>4</sub>Si<sub>8</sub>O<sub>31</sub>, Pb<sub>7</sub>Al<sub>2</sub>Si<sub>8</sub>O<sub>26</sub> and Pb<sub>7</sub>Al<sub>2</sub>Si<sub>10</sub>O<sub>30</sub> were found to coexist with oxide liquid. The PbO–AlO<sub>1.5</sub> binary and PbO–AlO<sub>1.5</sub>–SiO<sub>2</sub> ternary systems in air were reoptimized based on the obtained experimental data. New experimental results together with phase equilibria and thermodynamic literature data were used to obtain a self-consistent set of parameters of the thermodynamic model for all phases of the PbO–AlO<sub>1.5</sub>–SiO<sub>2</sub> system in air. The predicted liquidus projection of the PbO–AlO<sub>1.5</sub>–SiO<sub>2</sub> system was presented for the first time in the full range of temperatures and compositions.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":703,"journal":{"name":"Metals and Materials International","volume":"31 8","pages":"2228 - 2252"},"PeriodicalIF":4.0,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12540-024-01878-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145168676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The hot deformation behavior of powder metallurgy pure Mo is investigated by analyzing constitutive equations, the strain rate sensitivity (SRS) and temperature sensitivity (TS) coefficient distribution maps, and microstructure evolution. Hot compression tests are conducted at different temperatures and strain rates range of 1000–1300 °C and 0.005–1 s−1, with a constant true strain of 0.5. The results show that the flow behavior is greatly affected by deformation temperatures and strain rates, exhibiting typical hardening and softening stages. The constitutive equation is established, and the apparent activation energy Q is estimated as 456 kJ/mol. Furthermore, the SRS coefficient increases with increasing deformation temperature and decreasing strain rate, while the TS coefficient increases with increasing deformation temperature at high strain rates. Together with microstructure evolution, it shows an optimum hot working parameter of 1300 °C/0.005 s−1.
{"title":"Constitutive Equation and Processing Parameter Sensitivities for Hot Deformation of Pure Mo","authors":"Liying Yao, Yuan He, Liujie Xu, Zhou Li, Yimin Gao, Guojun Zhang","doi":"10.1007/s12540-024-01886-4","DOIUrl":"10.1007/s12540-024-01886-4","url":null,"abstract":"<div><p>The hot deformation behavior of powder metallurgy pure Mo is investigated by analyzing constitutive equations, the strain rate sensitivity (SRS) and temperature sensitivity (TS) coefficient distribution maps, and microstructure evolution. Hot compression tests are conducted at different temperatures and strain rates range of 1000–1300 °C and 0.005–1 s<sup>−1</sup>, with a constant true strain of 0.5. The results show that the flow behavior is greatly affected by deformation temperatures and strain rates, exhibiting typical hardening and softening stages. The constitutive equation is established, and the apparent activation energy Q is estimated as 456 kJ/mol. Furthermore, the SRS coefficient increases with increasing deformation temperature and decreasing strain rate, while the TS coefficient increases with increasing deformation temperature at high strain rates. Together with microstructure evolution, it shows an optimum hot working parameter of 1300 °C/0.005 s<sup>−1</sup>.</p><h3>Graphical Abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":703,"journal":{"name":"Metals and Materials International","volume":"31 8","pages":"2476 - 2485"},"PeriodicalIF":4.0,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145166962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 : 2025-01-20DOI: 10.1007/s12540-024-01885-5
Vitali Doroshenko, Andrey Aksenov, Anastasiya Fortuna, Leonid Gorlov, Alexey S. Prosviryakov, Stanislav Cherkasov, Daria Strekalina
The study examined the changes in microstructure, phase composition, processability during rolling, and mechanical properties of a new alloy from the Al–Mg-Ca-Mn system: Al3Mg2Ca0.8Mn. The findings regarding the as-cast structure revealed that, alongside the aluminum matrix, two eutectic intermetallic phases—Al4Ca and Al6(Mn,Fe)—were present. The aluminum matrix was notably enriched with magnesium and manganese, while calcium solubility remained below 0.1 wt%. Thermal analysis results aligned well with theoretical predictions. Following heat treatment at 440 °C6 hwater + 550 °C3 hair (SSHT), Al4Ca intermetallics were spheroidized, significantly improving the microstructure. Also after SSHT needle-like micron-sized Al10CaMn2 particles formed instead of Al6(Mn,Fe). The rolling performance of the novel alloy was examined along two paths. Samples rolled without prior homogenization (path 1) exhibited better mechanical properties compared to those processed under SSHT (path 2). The resistance to recrystallization was also better for path 1. This enhancement was attributed to nanosized Al6(Mn,Fe) precipitates, absent in the samples after SSHT. Overall, both methods of rolling highlighted the benefits of calcium alloying, with a notable increase in grain size by 60%, leading to decreased strength by 30% in calcium-free alloys (YS was 135/143 MPa vs. 110 MPa).
{"title":"Impact of Calcium Addition on Microstructural and Mechanical Properties of Al-3% Mg-0.8% Mn Alloy Under Different Treatment Paths","authors":"Vitali Doroshenko, Andrey Aksenov, Anastasiya Fortuna, Leonid Gorlov, Alexey S. Prosviryakov, Stanislav Cherkasov, Daria Strekalina","doi":"10.1007/s12540-024-01885-5","DOIUrl":"10.1007/s12540-024-01885-5","url":null,"abstract":"<div><p>The study examined the changes in microstructure, phase composition, processability during rolling, and mechanical properties of a new alloy from the Al–Mg-Ca-Mn system: Al3Mg2Ca0.8Mn. The findings regarding the as-cast structure revealed that, alongside the aluminum matrix, two eutectic intermetallic phases—Al<sub>4</sub>Ca and Al<sub>6</sub>(Mn,Fe)—were present. The aluminum matrix was notably enriched with magnesium and manganese, while calcium solubility remained below 0.1 wt%. Thermal analysis results aligned well with theoretical predictions. Following heat treatment at 440 °C6 hwater + 550 °C3 hair (SSHT), Al<sub>4</sub>Ca intermetallics were spheroidized, significantly improving the microstructure. Also after SSHT needle-like micron-sized Al<sub>10</sub>CaMn<sub>2</sub> particles formed instead of Al<sub>6</sub>(Mn,Fe). The rolling performance of the novel alloy was examined along two paths. Samples rolled without prior homogenization (path 1) exhibited better mechanical properties compared to those processed under SSHT (path 2). The resistance to recrystallization was also better for path 1. This enhancement was attributed to nanosized Al<sub>6</sub>(Mn,Fe) precipitates, absent in the samples after SSHT. Overall, both methods of rolling highlighted the benefits of calcium alloying, with a notable increase in grain size by 60%, leading to decreased strength by 30% in calcium-free alloys (YS was 135/143 MPa <i>vs.</i> 110 MPa).</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":703,"journal":{"name":"Metals and Materials International","volume":"31 8","pages":"2363 - 2379"},"PeriodicalIF":4.0,"publicationDate":"2025-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145167766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 : 2025-01-18DOI: 10.1007/s12540-024-01882-8
L. T. Pan, F. L. Shen, T. J. Ma, C. C. Li, W. H. Xin, X. Y. Fang
The addition of WC to metallic materials has been proved to be an effective way to improve the mechanical strength using fusion-based additive manufacturing, such as laser power-bed fusion (LPBF). What happened to WC particles is a key to understand it role in the strengthening mechanism during LPBF. This study investigated the whereabout of WC powders when in-situ added to IN625 alloys and its effect on the microstructure and mechanical properties of the samples fabricated by LPBF. It was found that there are basically three whereabouts of WC: decomposed products of C and W2C, remained WC, and dissolved WC. The former significantly promotes nanoprecipitation along the solidification cellular boundaries, which is coincident with dislocation walls. The addition of WC refined the size of solidification cells and grains, and weaken the columnar morphology of the grain as well. The yield strength for the samples when added 5% and 10% WC reaches 763.2 MPa and 1038.7 MPa, respectively. WC particles play an indirect role in improving strength via decomposition of WC and promoting nano-precipitate along cellular boundaries. Among the various strengthening mechanisms, nano-precipitation becomes predominant as WC increase, which accounts for 41.6% of the increment in yield strength.
{"title":"Effects of WC Addition on the Microstructure and Mechanical Properties of Inconel 625 Alloys Fabricated by Laser Powder Bed Fusion","authors":"L. T. Pan, F. L. Shen, T. J. Ma, C. C. Li, W. H. Xin, X. Y. Fang","doi":"10.1007/s12540-024-01882-8","DOIUrl":"10.1007/s12540-024-01882-8","url":null,"abstract":"<div><p>The addition of WC to metallic materials has been proved to be an effective way to improve the mechanical strength using fusion-based additive manufacturing, such as laser power-bed fusion (LPBF). What happened to WC particles is a key to understand it role in the strengthening mechanism during LPBF. This study investigated the whereabout of WC powders when in-situ added to IN625 alloys and its effect on the microstructure and mechanical properties of the samples fabricated by LPBF. It was found that there are basically three whereabouts of WC: decomposed products of C and W<sub>2</sub>C, remained WC, and dissolved WC. The former significantly promotes nanoprecipitation along the solidification cellular boundaries, which is coincident with dislocation walls. The addition of WC refined the size of solidification cells and grains, and weaken the columnar morphology of the grain as well. The yield strength for the samples when added 5% and 10% WC reaches 763.2 MPa and 1038.7 MPa, respectively. WC particles play an indirect role in improving strength via decomposition of WC and promoting nano-precipitate along cellular boundaries. Among the various strengthening mechanisms, nano-precipitation becomes predominant as WC increase, which accounts for 41.6% of the increment in yield strength.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":703,"journal":{"name":"Metals and Materials International","volume":"31 8","pages":"2500 - 2511"},"PeriodicalIF":4.0,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145166194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 : 2025-01-16DOI: 10.1007/s12540-024-01877-5
Jie Chen, Minghao Hu, Chong Li, Huijun Li, Xingchuan Xia
Transient liquid phase (TLP) bonding technology was effectively used to join a Ni-based superalloy using a BNi-2 amorphous interlayer. The TLP joint consisted of isothermal solidification zone (ISZ) with γ + γ′ phase and diffusion affected zone (DAZ) with granular borides. A post weld heat treatment (PWHT) process was subsequently employed to homogenize the joint microstructure and reduce the compositional fluctuation. Creep tests conducted under 800 ℃ and 120 MPa revealed that both the TLP and TLP + PWHT samples exhibited similar γ′ phase shearing deformation modes and intergranular fracture characteristics. Through PWHT process, the small ISZ grains were eliminated and the oxidation resistance of the joint was enhanced, reducing the cracking tendency of the joint grain boundaries. Therefore, the creep life of the TLP bonded sample is significantly prolonged from 367 h to 1034 h after PWHT process.
{"title":"Effect of Post Weld Heat Treatment on Microstructure and Creep Property of the TLP Bonded Ni-Based Superalloy","authors":"Jie Chen, Minghao Hu, Chong Li, Huijun Li, Xingchuan Xia","doi":"10.1007/s12540-024-01877-5","DOIUrl":"10.1007/s12540-024-01877-5","url":null,"abstract":"<div><p>Transient liquid phase (TLP) bonding technology was effectively used to join a Ni-based superalloy using a BNi-2 amorphous interlayer. The TLP joint consisted of isothermal solidification zone (ISZ) with γ + γ′ phase and diffusion affected zone (DAZ) with granular borides. A post weld heat treatment (PWHT) process was subsequently employed to homogenize the joint microstructure and reduce the compositional fluctuation. Creep tests conducted under 800 ℃ and 120 MPa revealed that both the TLP and TLP + PWHT samples exhibited similar γ′ phase shearing deformation modes and intergranular fracture characteristics. Through PWHT process, the small ISZ grains were eliminated and the oxidation resistance of the joint was enhanced, reducing the cracking tendency of the joint grain boundaries. Therefore, the creep life of the TLP bonded sample is significantly prolonged from 367 h to 1034 h after PWHT process.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":703,"journal":{"name":"Metals and Materials International","volume":"31 8","pages":"2266 - 2278"},"PeriodicalIF":4.0,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145166057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 : 2025-01-16DOI: 10.1007/s12540-024-01879-3
Yang Man, Jian Haigen, Fang Wu, Liu Yi
In order to explore the microstructure and mechanical properties of CX stainless steel formed by selective laser melting, the chemical composition, microstructure and properties of the samples were analyzed by optical microscope, X-ray diffractometer, scanning electron microscope and backscattered electron diffraction technology. The results show that the temperature gradient and high cooling rate have an important influence on the microstructure and anisotropy of SLM formed CX stainless steel. CX stainless steel is mainly composed of a large amount of martensite structure and a small amount of austenite phase struct-ure, and the three-dimensional microstructure is obviously different. In the three-dimensional section, the texture of < 110 > crystal orientation in XOZ plane is the strongest, followed by YOZ, and the specific orientation of grains in XOY plane is the weakest. In comparison, the XOZ plane has the best mechanical properties, and its tensile strength, yield strength, elongation and microh-ardness reach 1045.29 MPa, 829.51 MPa, 16.70% and 364.89 HV, respectively.
{"title":"Three-Dimensional Microstructure and Mechanical Properties of CX Stainless Steel Formed by Selective Laser Melting","authors":"Yang Man, Jian Haigen, Fang Wu, Liu Yi","doi":"10.1007/s12540-024-01879-3","DOIUrl":"10.1007/s12540-024-01879-3","url":null,"abstract":"<div><p>In order to explore the microstructure and mechanical properties of CX stainless steel formed by selective laser melting, the chemical composition, microstructure and properties of the samples were analyzed by optical microscope, X-ray diffractometer, scanning electron microscope and backscattered electron diffraction technology. The results show that the temperature gradient and high cooling rate have an important influence on the microstructure and anisotropy of SLM formed CX stainless steel. CX stainless steel is mainly composed of a large amount of martensite structure and a small amount of austenite phase struct-ure, and the three-dimensional microstructure is obviously different. In the three-dimensional section, the texture of < 110 > crystal orientation in XOZ plane is the strongest, followed by YOZ, and the specific orientation of grains in XOY plane is the weakest. In comparison, the XOZ plane has the best mechanical properties, and its tensile strength, yield strength, elongation and microh-ardness reach 1045.29 MPa, 829.51 MPa, 16.70% and 364.89 HV, respectively.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":703,"journal":{"name":"Metals and Materials International","volume":"31 8","pages":"2352 - 2362"},"PeriodicalIF":4.0,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145166055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 : 2025-01-11DOI: 10.1007/s12540-024-01881-9
Donghun Lee, Baek-Seok Seong, Byungrok Moon, Bong Cheon Park, Changhoon Lee, Sung-Dae Kim, Namhyun Kang
Austenitic stainless steels possess excellent properties; however, their low yield strengths limit their applications in structural settings. In this study, neutron diffraction was employed along with conventional microstructural characterization to investigate the microstructural and strain behaviors of reverted and deformed austenites in specimens rolled under cryogenic temperature (CRT) and room temperature (RT) and annealed at various temperatures, where different reversion mechanisms occur. After austenite reversion annealing, the yield strength was superior to that of the as-received specimens, regardless of the rolling conditions. The CRT specimens showed high strengths owing to grain refinement. They were composed of strain-induced martensite, leading to the formation of fine reverted austenite. The RT specimens consisted mostly of deformed austenite, resulting in coarse austenite. For the annealing at 590 °C, the reverted austenite grew under strain induced by the martensite. At 900 °C, recrystallization occurred during the heating process, with the fine grains growing preferentially, decreasing the yield strength. At 750 °C, reverted austenite formed through both the diffusional and diffusionless mechanisms. The diffusionally reverted austenite grew without strain, forming abnormally coarse grains, whereas the diffusionless reverted austenite produced recrystallized fine grains. Neutron diffraction analysis revealed that the annealed CRT specimens underwent full recrystallization and the RT specimens underwent incomplete recrystallization, indicating that the deformed austenite recrystallized more slowly than the diffusionless reverted austenite. Superior yield strength and elongation were achieved by annealing at the CRT for 1 min owing to the grain refinement combined with diffusional reverted austenite and diffusionless reverted austenite.
{"title":"Mechanisms of Reverted Austenite and Grain Refinement via Neutron Diffraction for Enhancing Mechanical Properties of 304 Stainless Steel","authors":"Donghun Lee, Baek-Seok Seong, Byungrok Moon, Bong Cheon Park, Changhoon Lee, Sung-Dae Kim, Namhyun Kang","doi":"10.1007/s12540-024-01881-9","DOIUrl":"10.1007/s12540-024-01881-9","url":null,"abstract":"<div><p>Austenitic stainless steels possess excellent properties; however, their low yield strengths limit their applications in structural settings. In this study, neutron diffraction was employed along with conventional microstructural characterization to investigate the microstructural and strain behaviors of reverted and deformed austenites in specimens rolled under cryogenic temperature (CRT) and room temperature (RT) and annealed at various temperatures, where different reversion mechanisms occur. After austenite reversion annealing, the yield strength was superior to that of the as-received specimens, regardless of the rolling conditions. The CRT specimens showed high strengths owing to grain refinement. They were composed of strain-induced martensite, leading to the formation of fine reverted austenite. The RT specimens consisted mostly of deformed austenite, resulting in coarse austenite. For the annealing at 590 °C, the reverted austenite grew under strain induced by the martensite. At 900 °C, recrystallization occurred during the heating process, with the fine grains growing preferentially, decreasing the yield strength. At 750 °C, reverted austenite formed through both the diffusional and diffusionless mechanisms. The diffusionally reverted austenite grew without strain, forming abnormally coarse grains, whereas the diffusionless reverted austenite produced recrystallized fine grains. Neutron diffraction analysis revealed that the annealed CRT specimens underwent full recrystallization and the RT specimens underwent incomplete recrystallization, indicating that the deformed austenite recrystallized more slowly than the diffusionless reverted austenite. Superior yield strength and elongation were achieved by annealing at the CRT for 1 min owing to the grain refinement combined with diffusional reverted austenite and diffusionless reverted austenite.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":703,"journal":{"name":"Metals and Materials International","volume":"31 8","pages":"2279 - 2296"},"PeriodicalIF":4.0,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145164830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 : 2025-01-11DOI: 10.1007/s12540-024-01875-7
Wontae Cho, Ho Hyeong Lee, Dong-Woo Suh
The influence of microstructure on tensile properties and stretch-flangeability of TRIP steels with tensile strengths higher than 1.0 GPa has been investigated under various Quenching and Partitioning conditions. Lowering the quenching stop temperature (QT) from 300 °C to 190 °C after intercritical annealing increased the volume fraction of tempered martensite (TM), decreased that of bainite, and maintains that of ferrite and retained austenite constant in the final microstructure. 300 °C was Ms temperature, thus, QT 300 °C sample consisted of negligible TM and 36% bainite. So, as the QT was reduced to 190 °C, the TM phase was integrated into the bainite up to 13.8%. The yield strength (YS), tensile strength (TS), and hole expansion ratio (HER) of QT 300 °C steel were inferior compared to that of QT 190 °C steel; however, the total elongation was improved by 2.9% for QT 300 °C steel. The elevated YS and TS of the QT 190 °C steel were attributed to the increased micro hardness caused by the increased TM fraction. Furthermore, the high HER of the QT 190 °C steel was elucidated by the reduced micro void formation compared to the QT 300 °C steel under the same reduction ratio. That was because QT 300 °C steel, comprised mainly of bainite, has a higher fraction of blocky retained austenite that, when subjected to deformation, transforms into mechanically induced blocky martensite, acting as a significant source of micro voids. Finally, enhanced total elongation in QT 300 °C steel was attributed to more stable retained austenite during deformation compared to the QT 190 °C steel.
{"title":"Effect of Microstructure on Mechanical Properties of 1.0G TRIP Steels Produced by Quenching and Partitioning (Q&P) Process","authors":"Wontae Cho, Ho Hyeong Lee, Dong-Woo Suh","doi":"10.1007/s12540-024-01875-7","DOIUrl":"10.1007/s12540-024-01875-7","url":null,"abstract":"<div><p>The influence of microstructure on tensile properties and stretch-flangeability of TRIP steels with tensile strengths higher than 1.0 GPa has been investigated under various Quenching and Partitioning conditions. Lowering the quenching stop temperature (QT) from 300 °C to 190 °C after intercritical annealing increased the volume fraction of tempered martensite (TM), decreased that of bainite, and maintains that of ferrite and retained austenite constant in the final microstructure. 300 °C was Ms temperature, thus, QT 300 °C sample consisted of negligible TM and 36% bainite. So, as the QT was reduced to 190 °C, the TM phase was integrated into the bainite up to 13.8%. The yield strength (YS), tensile strength (TS), and hole expansion ratio (HER) of QT 300 °C steel were inferior compared to that of QT 190 °C steel; however, the total elongation was improved by 2.9% for QT 300 °C steel. The elevated YS and TS of the QT 190 °C steel were attributed to the increased micro hardness caused by the increased TM fraction. Furthermore, the high HER of the QT 190 °C steel was elucidated by the reduced micro void formation compared to the QT 300 °C steel under the same reduction ratio. That was because QT 300 °C steel, comprised mainly of bainite, has a higher fraction of blocky retained austenite that, when subjected to deformation, transforms into mechanically induced blocky martensite, acting as a significant source of micro voids. Finally, enhanced total elongation in QT 300 °C steel was attributed to more stable retained austenite during deformation compared to the QT 190 °C steel.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":703,"journal":{"name":"Metals and Materials International","volume":"31 8","pages":"2253 - 2265"},"PeriodicalIF":4.0,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145164831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 : 2025-01-11DOI: 10.1007/s12540-024-01871-x
V. V. Popov, E. N. Popova, E. V. Osinnikov
The effect of severe plastic deformation by high-pressure torsion (HPT) on the formation of nanocrystalline structure in niobium has been studied by the methods of transmission electron microscopy, scanning tunneling microscopy, X-ray diffraction analysis and microhardness measurements. The thermal stability of the resulting structure has been analyzed. Specific features of grain boundaries (GBs) formed under the severe plastic deformation have been considered and analyzed. It is demonstrated that a considerable fraction of these boundaries are in the so-called nonequilibrium, or deformation-modified state, characterized by higher free energy and larger free volume in comparison with those of common relaxed GBs. It has been shown that contribution of nonequilibrium GBs to total strengthening is relatively small.
{"title":"Effect of Severe Plastic Deformation on the Structure and State of Grain Boundaries in Niobium","authors":"V. V. Popov, E. N. Popova, E. V. Osinnikov","doi":"10.1007/s12540-024-01871-x","DOIUrl":"10.1007/s12540-024-01871-x","url":null,"abstract":"<div><p>The effect of severe plastic deformation by high-pressure torsion (HPT) on the formation of nanocrystalline structure in niobium has been studied by the methods of transmission electron microscopy, scanning tunneling microscopy, X-ray diffraction analysis and microhardness measurements. The thermal stability of the resulting structure has been analyzed. Specific features of grain boundaries (GBs) formed under the severe plastic deformation have been considered and analyzed. It is demonstrated that a considerable fraction of these boundaries are in the so-called nonequilibrium, or deformation-modified state, characterized by higher free energy and larger free volume in comparison with those of common relaxed GBs. It has been shown that contribution of nonequilibrium GBs to total strengthening is relatively small.</p><h3>Graphical Abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":703,"journal":{"name":"Metals and Materials International","volume":"31 7","pages":"2069 - 2081"},"PeriodicalIF":4.0,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145164027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The preparation of Ni–Co dual phase cladding layer on the surface of ductile iron can effectively improve its wear resistance and corrosion resistance. Quantifying the forming process of Ni–Co composite cladding layer can provide an important theoretical basis for improving the service life of cladding layer. In this study, a three-dimensional numerical model and a molecular dynamics (MD) model of Ni–Co composite coating multi-layer cladding forming were established from both macroscopic and microscopic perspectives. The transient evolution of the temperature, height, energy, crystal structure and radial distribution function during Ni–Co composite coating multi-layer cladding forming were calculated and revealed. The results showed that the temperature of the first Ni-based cladding layer was slightly lower than that of the second Co-based cladding layer, and the height was slightly higher than that of the second Co-based cladding layer. When the first Ni-based cladding layer was formed, the content of FCC crystals was the highest, and the content of HCP and BCC crystals was very small. When the second Co-based cladding layer was formed, FCC crystals were the most, followed by HCP, BCC crystals were the least. The XRD results were consistent with the numerical results, which verified the reliability of the numerical calculation.
{"title":"Mechanism Study on Forming Process of QT600 Laser Cladding Ni–Co Dual Phase Cladding Layer","authors":"Chang Li, Menghui Yu, Siyu Li, Yichang Sun, Jiangtao Zhao, Xing Han, Cong Wang","doi":"10.1007/s12540-024-01880-w","DOIUrl":"10.1007/s12540-024-01880-w","url":null,"abstract":"<div><p>The preparation of Ni–Co dual phase cladding layer on the surface of ductile iron can effectively improve its wear resistance and corrosion resistance. Quantifying the forming process of Ni–Co composite cladding layer can provide an important theoretical basis for improving the service life of cladding layer. In this study, a three-dimensional numerical model and a molecular dynamics (MD) model of Ni–Co composite coating multi-layer cladding forming were established from both macroscopic and microscopic perspectives. The transient evolution of the temperature, height, energy, crystal structure and radial distribution function during Ni–Co composite coating multi-layer cladding forming were calculated and revealed. The results showed that the temperature of the first Ni-based cladding layer was slightly lower than that of the second Co-based cladding layer, and the height was slightly higher than that of the second Co-based cladding layer. When the first Ni-based cladding layer was formed, the content of FCC crystals was the highest, and the content of HCP and BCC crystals was very small. When the second Co-based cladding layer was formed, FCC crystals were the most, followed by HCP, BCC crystals were the least. The XRD results were consistent with the numerical results, which verified the reliability of the numerical calculation.</p><h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":703,"journal":{"name":"Metals and Materials International","volume":"31 8","pages":"2332 - 2351"},"PeriodicalIF":4.0,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145164344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号