等温锻造温度对TC18钛合金组织性能的影响  

Effect of isothermal forging temperature on microstructure and mechanical properties of TC18 alloy

作　　者：王晓燕[1] 郭鸿镇[1] 袁士翀[1] 姚泽坤[1] 魏寿庸[2] 王鼎春[2] 

机构地区：[1]西北工业大学材料学院,陕西西安710072 [2]宝鸡有色金属加工厂,陕西宝鸡721014

出　　处：《锻压技术》2008年第3期8-11,共4页Forging & Stamping Technology

摘　　要：研究了TC18钛合金在5.5×10-4s-1恒应变速率下、60%大变形等温锻造时,温度变化对合金组织和性能的影响。结果表明:显微组织对温度变化敏感,在两相区锻造时,显微组织由初生α相和β转变组织组成,随着锻造温度的升高,初生α相的含量逐渐减少,尺寸增大,等轴化程度增加;在相变点以上锻造时为魏氏组织。室温和高温拉伸强度随锻造温度的升高不断增加,拉伸塑性不断降低,室温冲击韧性也呈下降趋势。在860℃等温锻造时,显微组织为双态组织,强度和塑性达到最佳配合,获得良好的综合力学性能。860℃为较佳等温锻造温度。The effect of isothermal forging temperature on microstructure and mechanical properties of TC18 alloy was studied by isothermal forging at the strain rate of 5.5×10^-4s^-1 and 60% deformation. The result indicates that the microstructure of TC18 alloy is sensitive to forging temperature. The microstructure consists of primary a and transition β phase when the alloy is deformed in α＋β field. The volume fraction of primary a decreases and its size increases with the rising of the temperature. Typical Widmanstaten structure can be obtained when forging above transformation point. The tensile strength is enhanced with the temperature being increased and the tensile ductility and the impact property reduce. When forging at 860 ℃, bimodal structure could be obtained, the tensile strength and the plasticity were in best combination. So 860 ℃ is a better option in isothermal forging.

关 键 词：TC18钛合金 等温锻造温度 初生Α相 力学性能 

分 类 号：TG319[金属学及工艺—金属压力加工]