微量B添加对铸态Ti-6Al-4V合金组织及性能的影响(英文)  

Effect of Trace Boron Addition on Microstructure and Properties of as-Cast Ti-6Al-4V Alloy

作　　者：于洋[1] 李成林[1] 付艳艳[1] 惠松骁[1] 叶文君[1] 

机构地区：[1]北京有色金属研究总院有色金属材料制备加工国家重点实验室,北京100088

出　　处：《稀有金属材料与工程》2014年第12期2908-2911,共4页Rare Metal Materials and Engineering

基　　金：International S&T Cooperation Program of China(ISTCP)(2013DFG52920)

摘　　要：通过添加0.1wt%B对铸态Ti-6Al-4V合金组织和性能影响研究表明:微量B添加在合金中形成Ti B相,Ti B相位于原始β晶界处。微量的B添加使得原始β晶粒和α集束都得到了明显的细化,获得的铸态组织更加均匀。微量的B添加同时提高了铸态合金的强度和塑性,并改变了合金的拉伸断裂机制。由微空洞在α集束交界处聚集、长大及裂纹形成扩展改变为Ti B相与基体合金的变形不协调造成微裂纹的形成和扩展。The effects of 0. 1 wt% boron addition on microstructures and properties of as-cast Ti-6Al-4V alloy were studied. The re- suits show that TiB phase forms in the original β grain boundaries of Ti-6Al-4V alloy due to 0.1% boron addition. Compared with boron-free Ti-6Al-4V alloy, boron added alloy is refined with uniform β grains. In addition, boron addition results in an improved strength, ductility and a changed fracture mechanism. The fracture mechanism of Ti-6Al-4V alloy is as follows： dislocation slip and pile up in the alpha colonies results in stress concentration and then voids growing until cracks forming. However, the fracture of the boron added Ti-6A1-4V alloy is as follows： a stress concentration occurs around the TiB phase and then micro-voids are formed. TiB phase breaks and is separated with the matrix and then cracks nucleate.

关 键 词：钛合金 铸态组织 性能 硼添加 

分 类 号：TG146.23[一般工业技术—材料科学与工程]