通过再结晶退火实现剪切-压缩变形态GH4169高温合金的显微组织均匀化
Microstructure Homogenization of GH4169 Superalloy in Shear-Compression Deformation State by Recrystallization Annealing
陈乐利 1高佩 2罗锐 3程晓农 1孟宪凯4
作者信息
- 1. 江苏大学材料科学与工程学院,江苏镇江 212013
- 2. 江苏银环精密钢管有限公司技术管理部,江苏宜兴 214200
- 3. 江苏大学材料科学与工程学院,江苏镇江 212013;重庆大学先进装备机械传动国家重点实验室,重庆 400044
- 4. 江苏大学机械工程学院,江苏镇江 212013
- 折叠
摘要
GH4169高温合金在剪切-压缩变形后容易出现区域性微结构特征,这不利于后续的冷轧加工.在1000～1080 ℃温度范围内,保温1～3h条件下进行再结晶退火处理以研究GH4169高温合金的微观组织演变行为,并通过调节晶粒大小优化其冷成形性能.结果表明,静态再结晶(SRX)在1000 ℃时完全形核,原有的粗大晶粒完全被细小的再结晶晶粒取代.大角度晶界(HAGB)的弓出位置是SRX的首选形核点.经1020～1060 ℃退火后,部分相邻的SRX晶粒之间发生吞并,导致一部分晶粒的尺寸增大,而初始动态再结晶(DRX)晶粒在应变集中区域仍保持微小的尺寸.再结晶晶粒(包括SRX和DRX)经1080 ℃退火后均匀长大,平均晶粒尺寸为87.89 μm,此时显微组织的区域特征完全消失,组织均匀化程度明显提高.由于SRX的生长事故,经1080 ℃退火后出现了阶梯状孪晶,且孪晶界(Σ3)的长度分数达到35.8％,这有利于提高GH4169高温合金的高温持久性能.剪切-压缩变形态GH4169高温合金的最佳再结晶退火工艺最终被确定为1080 ℃保温1h,水冷.
Abstract
Regional microstructure characteristic always appears in shear-compression deformed GH4169 superalloy,which is detrimental to subsequent cold-rolling process in engineering.Recrystallization annealing treatments within temperature range of 1000-1080 ℃ and holding time range of 1-3 h were carried out to investigate the microstructure evolution behavior,and the cold-forming property of GH4169 superalloy was optimized by regulating the grain size.Results show that static recrystallization(SRX)grains are fully nucleated at 1000 ℃ and the original coarse grains are completely replaced by fine recrystallized grains.Bulges of high angle grain boundaries are the preferred nucleation points of SRX.At 1020-1060 ℃,grain annexation takes place among adjacent SRX grains,causing partial grains to increase,while the original dynamic recrystallization(DRX)grains keeps tiny in the strain con-centration region.Recrystallized grains(both SRX and DRX)uniformly grow up,with an average grain size of 87.89 μm at 1080 ℃,at which the regional characteristic completely disappears,and the microstructure is significantly homogenized.Step twins appear at 1080 ℃ due to the SRX growth accidents,and the length fraction of twin boundaries(Σ3)reaches 35.8％,which can effectively improve the high temperature resistance of GH4169 superalloy.Ultimately,the optimal recrystallization annealing of shear-compression deformed GH4169 superalloy is determined as 1080 ℃-1 h,followed by water cooling.
关键词
GH4169高温合金/再结晶退火/显微组织/再结晶/孪晶Key words
GH4169 superalloy/recrystallization annealing/microstructure/recrystallization/twins引用本文复制引用
基金项目
State Key Laboratory of Mechanical Transmission for Advanced Equipment Project(SKLMT-MSKFKT-202219)
Natural Science Foundation of Jiangsu Province(BK20220548)
Open Research Fund from the State Key Lab of Advanced Metals and Materials,University of Science and Technology Beijing(2022-Z21)
National Natural Science Foundation of China(52005223)
出版年
2024
NETL
NSTL
万方数据