Ti-22Al-25Nb合金热机械处理组织与性能研究  

Microstructure and Mechanical Properties of Ti-22Al-25Nb Alloy during Hot Mechanical Processing

作　　者：马雄[1] 张建伟[1] 梁晓波[1] 曾卫东[2] 

机构地区：[1]钢铁研究总院,北京100081 [2]西北工业大学凝固技术国家重点实验室,陕西西安710072

出　　处：《稀有金属材料与工程》2017年第5期1375-1379,共5页Rare Metal Materials and Engineering

摘　　要：研究了Ti-22Al-25Nb合金的显微组织和力学性能,重点介绍了等温锻造温度、固溶时效处理对合金力学性能的影响规律。结果表明:随着等温锻造温度的升高,合金的强度和塑性先增加后降低。在O+B2两相区固溶时,随着固溶温度的升高,具有较高塑性的B2相体积分数的增加和等轴颗粒的减少是合金具有较高塑性的主要原因;而在α_2+B2+O3相区固溶时,片层厚度的减小有利于合金强度的提高,但过大的B2相晶粒尺寸和较细的片层厚度则对合金的塑性不利。相的含量、形态、尺寸对合金力学性能的影响较大,尽可能在B2相变点附近进行等温锻造,以控制等轴颗粒数量和B2相晶粒尺寸,在低温时效以获得较细的片层组织从而提高合金的强度和塑性。The microstructure and mechanical properties of Ti-22AI-25Nb alloy was investigated and the effects of the forging, solution and aging temperature on the mechanical properties were discussed. Results show that as the isothermal forging temperature increases, the strength and ductility of the alloy increase at first and then decrease. When the solution is conducted in O＋B2 region, as the solution temperature increases, the increasing B2 volume and decreasing particle amount are the main reason for high ductility of the alloy. When the solution is conducted in α2＋B2＋O region, the decrease of lamellar thickness is beneficial for the strength increasing while the large B2 grain size and fine lamella are harmful for the ductility. The phase volume, morphology and size have a significant influence on the mechanical properties of the alloy. A basic principle to improve the tensile property of the alloy is isothermal forging nearby the B2-transus in order to control the amount ： - of the particles and the B2 grain size, and the subsequent aging is at low temperature to obtain fine lamella.

关 键 词：TI2ALNB基合金 热处理 显微组织 力学性能 

分 类 号：TG146.23[一般工业技术—材料科学与工程]