动高压加载条件下Ti-6Al-4V和Ti-47Nb合金层裂微结构特征与断裂机理  

Spall Microstructure Characteristics and Fracture Mechanism of Ti-6Al-4V and Ti-47Nb Alloys under Dynamic High-pressure Loading

作　　者：刘慧[1] 于晓东[2] 谭成文[2] 赵慧林 陈秀娟[3] Liu Hui1, Yu Xiaodong2, Tan Chengwen2, Zhao Huilin2, Chen Xiujuan3(1. State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals, Lanzhou University of Technology, Lanzhou 730050, China） （2. Beijing Institute of Technology, Beijing 100081, China） （3. School of Mechanical and Electronical Engineering, Lanzhou University of Technology, Lanzhou 730050, China)

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,甘肃兰州730050 [2]北京理工大学,北京100081 [3]兰州理工大学机电工程学院,甘肃兰州730050

出　　处：《稀有金属材料与工程》2018年第3期829-834,共6页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51001014)

摘　　要：利用平板撞击实验和样品软回收技术,结合光学显微镜(OM)、扫描电子显微镜(SEM)等微观分析手段,研究了动高压加载条件下Ti-6Al-4V和Ti-47Nb 2种不同类型钛合金的层裂微结构特征与断裂机理。结果表明:Ti-6Al-4V合金的抗层裂破坏能力强于Ti-47Nb合金,其原因在于Ti-6Al-4V合金的高强度。Ti-6Al-4V合金层裂微孔洞大多在α/β两相界面处形核并沿相界扩展,而Ti-47Nb合金中的微裂纹是通过微孔洞直接连通形成。随后汇合的大空洞或大裂纹间形成的绝热剪切带(ASB)加速了试样层裂破坏的产生,Ti-6Al-4V与Ti-47Nb合金均表现出了韧性断裂特征。Spall microstructure characteristics and fracture mechanism of Ti-6Al-4V and Ti-47Nb alloys were studied by plate impact experiments and＂sample soft-capture＂technology under the dynamic high-pressure loading,as well as microscopic analyses using optical microscopy and scanning electronic microscopy.The results indicate that Ti-6Al-4V alloy has stronger ability of spall resistance than Ti-47Nb alloy because of the high strength of Ti-6Al-4V alloys.The micro-voids in the spalled Ti-6Al-4V alloy almost nucleate at theα/βphase boundaries and propagate along the phase boundaries,and the micro-cracks of Ti-47Nb alloy are directly connected through micro-voids.Subsequently,the adiabatic shear band（ASB）,which forms between macroscopic voids or main cracks,promotes the spall fracture of samples.Ti-6Al-4V and Ti-47Nb alloys fracture with ductile characteristics.

关 键 词：钛合金 软回收 层裂 断裂机理 

分 类 号：TG146.23[一般工业技术—材料科学与工程]