摘要
研究了Ti6321合金等轴、双态和魏氏组织室温下706 MPa拉伸应力作用200 h的蠕变行为,采用TEM观察了Ti6321合金不同组织拉伸蠕变后的微观组织形貌,并通过迹线法分析了位错滑移类型。结果表明:Ti6321合金等轴组织的蠕变应变最大,双态组织次之,魏氏组织最小。通过对蠕变曲线进行一阶求导,找到蠕变速率变化转折点,得到不同阶段的蠕变应变,发现初始蠕变应变大小与组织中残留的位错量成正相关。Ti6321合金室温蠕变机制主要是位错滑移,拉伸蠕变过程中等轴组织发生了原始胞状位错分解和新位错滑移的形成,该位错为(1011)<1123>交滑移;双态组织初始α相发生了{1010}<1120>柱面滑移,次生α相发生了(1101)<1120>锥面滑移;魏氏组织发生(0001)<2110>基面滑移的可能性大,发生(1011)<1012>锥面滑移的可能性较小。
The creep behavior of equiaxed,duplex and widmanstatten structures of Ti6321 alloy under tensile stress of 706MPa for 200h was studied.The microstructure morphology of the samples after creep was observed by metallographic microscope and transmission electron microscope(TEM),and the dislocation slip types of different microstructures of Ti6321 alloy were analyzed by trace method.The results show that the creep strain of equiaxed structure of Ti6321 alloy is the largest,followed by duplex structure and widmanstatten structure.Through the first derivative of creep curve,the turning point of creep rate change was found,and the creep strain of different stages was obtained.It is found that the primary creep strain is positively related to the amount of residual dislocation in the structure.The creep mechanism of Ti6321 alloy at room temperature is mainly dislocation slip,the original cellular dislocation decomposes and the new dislocation slip forms during the tensile process of equiaxed structure,the new dislocation is(10-11)<11-23>cross slip;the primaryαphase of duplex structure mainly occurs{10-10}<11-20>prismatic slip,the secondaryαphase occurs(-1101)<-2110>pyramidal slip;widmanstatten structure starts(0001)<-2110>basal slip and(10-11)<10-12>pyramidal slip.
作者
许玲玉
孙志杰
李冲
王洋
蒋鹏
张文豪
Xu Lingyu;Sun Zhijie;Li Chong;Wang Yang;Jiang Peng;Zhang Wenhao(Luoyang Ship Material Research Institute,Luoyang 471023,China)
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2024年第12期3383-3389,共7页
Rare Metal Materials and Engineering
基金
国家重点研发计划(2022YFB3705605)。
关键词
蠕变行为
蠕变机制
位错滑移
Creep behavior
Creep mechanism
Dislocation slip
