热处理制度对MRI用低铜比NbTi超导线材临界电流密度的影响  

Effect of Heat Treatment on Critical Current Density of MRI NbTi Superconducting Wire

作　　者：郭强[1,2] 王庆相[1,2] 刘建伟[1,2] 李建峰[1,2] 刘向宏[1,2] 冯勇[1,2] 

机构地区：[1]西部超导材料科技股份有限公司,陕西西安710018 [2]超导材料制备国家工程实验室,陕西西安710018

出　　处：《热加工工艺》2015年第18期203-205,208,共4页Hot Working Technology

基　　金：国家863专项资助项目(2014AA032701)

摘　　要：以高均匀性Nb47Ti合金锭和高纯无氧铜为原材料,制备了低铜比（1.3）的MRI（Magnetic Resonance Imaging）用Nb Ti/Cu超导线。研究了时效次数、时效时间和Nb47Ti棒材对Nb Ti/Cu超导线临界电流密度的影响。测试结果表明时效次数（3次）相同时,时效时间从120 h延长到200 h,临界电流密度基本无变化。时效4次后的临界电流密度较时效3次后大约提高234 A/mm2（4.2 K,5 T）,而时效4次和5次后的临界电流密度基本相同。经工艺优化后,时效次数为4次或5次时临界电流密度最高,为3158～3161 A/mm2（4.2 K,5 T,判据0.1μV/cm）。NbTi/Cu wire the low copper-to-superconductor ratio of 1.3 was prepared using high homogenous Nb47Ti alloy bar and oxygen-free copper firstly. The effects of heat treatment time and number on critical current density of Nb Ti superconducting wire were investigated. The results show that when the number of heat treatment（3 times） is the same,prolong of final heat treatment time from 120 h to 200 h,critical current density changes little. In addition,critical current density of wire heat treated for 4 times is 234 A/mm2（4.2 K,5 T） higher than that of heat treated for 3 times. However,critical current density of wire heat treated for 5 times and 4 times are almost the same. Measurement results show that the acquired maximum critical current density can reach 3158-3161 A/mm2 at 4.2 K and 5 T（criterion： 0.1 μV/cm）as the wire was heat treated for 4 or 5 times.

关 键 词：NbTi/Cu超导线 临界电流密度 时效次数 时效时间 

分 类 号：TG132.2[一般工业技术—材料科学与工程]