立方织构Ni-Cr-Mo-W合金薄带及其性能

摘要

为了得到高份额立方织构金属基带,同时兼顾居里温度和屈服强度的要求,设计了Ni-7.8％Cr-1.1％ Mo-1.6％W(原子分数)合金.采用冷坩埚悬浮熔炼技术冶炼合金铸锭,铸锭经过锻造、热轧、冷轧和再结晶退火,最终得到厚度为100μm的合金薄带.采用电子背散射衍射(EBSD)技术对合金薄带再结晶织构进行了表征,并研究了其磁性能及力学性能.结果表明:经大变形量冷轧和优化的两步法退火后Ni-7.8％Cr-1.1％Mo-1.6％W合金薄带立方织构份额为93.4％,小角晶界体积分数为84.5％;合金薄带的居里温度为25 K,远低于77 K;合金薄带室温下的屈服强度为182MPa,与Ni-5％W合金相当,且抗拉性能十分优异.%Quaternary Ni-7.8at％Cr-1.1at％Mo-1.6at％W alloy was designed based on the requirements of sharp cubic texture,lower Curie temperature and moderate yield strength for the substrate of 2G high temperature superconductor wire.The alloy ingot was prepared by using cold crucible induction levitation melting and a tape with a final thickness of 100 μm was obtained after forging,hot rolling,cold rolling and recrystallization annealing.The recrystallization texture of the alloy tape was characterized by electron back scatter diffraction (EBSD) technology and its magnetic and mechanical properties were also evaluated.The results show that the cubic texture percentage and the small angle grain boundary volume fraction of Ni-7.8at％ Cr-1.1at％ Mo-1.6at％ W alloy tape reach 93.4％ and 84.5％,respectively,after heavy cold rolling and two-step annealing.The Curie temperature of the alloy tape is 25 K,far below 77 K,and the yield strength of the alloy tape at room temperature is 182 MPa,equivalent to that of Ni-5at％W alloy tape.All this indicates that Ni-7.8at％Cr-1.1at％Mo-1.6at％W alloy tape possesses advantages over the available Ni-based alloy tapes and would substitute Ni-5at％W alloy tape for the coating of 2G high temperature superconductor.