初始状态对铝锂合金蠕变时效行为的影响及其机制  

Influence of Initial States on Creep Aging Behavior of 2195 Al-Li Alloy and Associated Mechanism

作　　者：张力文[1] ZHANG Liwen(Xi′an Aeronautical Polytechnic Institute,Xi′an 710089,China)

机构地区：[1]西安航空职业技术学院,西安710089

出　　处：《有色金属工程》2024年第7期68-72,100,共6页Nonferrous Metals Engineering

基　　金：陕西省教育厅2023年度科学研究计划资助项目(23JK0501)。

摘　　要：采用180℃、恒定应力140 MPa蠕变时效试验、室温力学拉伸试验和扫描电子显微镜(SEM)观察,分析了不同初始状态对2195铝锂合金蠕变时效行为的影响。结果表明,重固溶态合金的蠕变量最大,其次是峰时效态,回归态的试样则具有最小的蠕变变形。其屈服和抗拉强度顺序为重固溶态>峰时效态>回归态。而断裂伸长率依次为重固溶>峰时效>回归态。最后揭示了重固溶态的蠕变时效合金的高强韧性机制:晶内均匀分布的细小强化相(T_(1)相)和较窄的晶界无析出带的共同作用。Creep aging characteristics of 2195 Al-Li alloy with three initial tempers were investigated through creep aging tests conducted at 180℃and constant stress of 140 MPa as well as room temperature mechanical tensile tests and Scanning Electron Microscopy(SEM)observations.The research results indicate that the creep deformation of the alloy with resolution temper is the highest,followed by the peak aging temper,and the sample with regression temper has the smallest creep deformation.The order of yield and tensile strength is resolution temper>peak aging temper>regression temper.The elongation at break is in the order of resolution>peak aging>regression.Finally,the mechanism responsible for the high strength and toughness of the creep-aged alloy with resolution temper has been elucidated.It is attributed to the synergistic impact of the fine strengthening T_(1)phase evenly dispersed within the grains and the narrow precipitation-free zone width along grain boundaries.

关 键 词：铝锂合金 热处理 蠕变时效 

分 类 号：TB404[一般工业技术]