| 摘要: |
| 采用高温拉伸研究激光焊接头超塑性变形行为,分析了焊缝及热影响区在超塑性变形过程中的显微组织演变规律,并提出采用等轴化系数来表征焊缝组织的等轴化进程,采用平均晶粒尺寸来表征热影响区组织的转变程度.结果表明,随着变形的进行,等轴化系数逐渐升高;在相同变形量时,变形温度升高或初始应变速率降低均有利于等轴化系数上升,促进焊缝超塑性变形的进行.随着变形的进行,热影响区平均晶粒尺寸逐渐升高;在相同变形量时,变形温度升高或初始应变速率降低均有利于平均晶粒尺寸上升,促进焊缝超塑性变形的进行. |
| 关键词: 组织演变 激光焊 超塑性 |
| DOI： |
| 分类号: |
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| Microstructure evolution characterization of superplastic deformation of titanium alloy |
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CHENG Donghai1,2, HUANG Jihua2, CHEN Yiping1, HU Dean1
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1.School of Aeronautical Manufacturing Engineering, Nanchang Hangkong University, Nanchang 330063, China;2.School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
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| Abstract: |
| High temperature tensile test was used to investigate the superplastic deformation behavior of laser weld joint.Microstructure evolution principles of weld bead and HAZ during superplastic deformation were analyzed.Equiaxial rate was introduced to characterize the microstructure transition extent of weld bead, and average grain size was introduced to characterize the microstructure transition extent of HAZ.The results indicated that equiaxial rate increased with straining, and with forming temperature increasing.It also increased with strain rate decreasing.Average grain size increased with straining, and with forming temperature increasing. |
| Key words: microstructure evolution laser welding superplastic deformation |
