添加Zr的60NiTi合金的热处理工艺优化  

Optimization of heat treatment process for 60NiTi alloy with Zr addition

作　　者：毛济 余爱武 宋裔 施祥玲 夏巧伟 左舜贵 王博[1] 肖飞[3] MAO Ji;YU Ai-wu;SONG Yi;SHI Xiang-ling;XIA Qiao-wei;ZUO Shun-gui;WANG Bo;XIAO Fei(School of Materials and Science Engineering,Shanghai University of Engineering Science,Shanghai 201620,China;Shanghai Aerospace Equipments Manufacturer Co Ltd,Shanghai 200245,China;School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海工程技术大学材料科学与工程学院,上海201620 [2]上海航天设备制造总厂有限公司,上海200245 [3]上海交通大学材料科学与工程学院,上海200240

出　　处：《材料热处理学报》2023年第8期87-94,共8页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(52022055);上海市Ⅲ类高峰学科—材料科学与工程(高能束智能加工与绿色制造)。

摘　　要：60NiTi合金具有高硬度、低密度和耐磨等优异的性能,在航空航天领域有广泛的应用前景。为了进一步提高60NiTi合金的力学性能,研究了Zr的添加及热处理工艺对60NiTi合金组织与硬度的影响。结果表明:Zr的添加提高了60NiTi合金的硬度并使其组织更加均匀。此外,在炉冷、空冷、油冷和水冷4种不同的冷却方式中,炉冷60NiTiZr合金中存在大量粗大的析出相,硬度也最低。冷却速度最快的水冷处理的60NiTiZr合金的硬度最高,且能够避免粗大析出相形成,但存在残余应力较大的问题。对水冷60NiTiZr合金在300~600℃温度范围进行时效处理,发现随时效温度的升高,合金的硬度先升高后降低,且在500℃时效时硬度达到最高。进一步对水冷60NiTiZr合金在500℃进行不同时间的时效处理,发现时效2 h后合金硬度达到峰值(61.7 HRC),时效后期还出现缓慢的二次硬化现象。60NiTi alloy has excellent properties such as high hardness,low density and wear resistance,and has a broad application prospect in the aerospace field.In order to further improve the mechanical properties of the 60NiTi alloy,the effects of Zr addition and heat treatment process on microstructure and hardness of the 60NiTi alloy were studied.The results show that the addition of Zr improves the hardness of the 60NiTi alloy and makes its microstructure more uniform.In addition,among the four different cooling methods of furnace cooling,air cooling,oil cooling,and water cooling,there are a large number of coarse precipitates in the furnace-cooled 60NiTiZr alloy,with the lowest hardness.The water-cooled 60NiTiZr alloy with the fastest cooling rate has the highest hardness and can avoid the formation of coarse precipitates,but there is a problem of large residual stress.After aging treatment of the water cooled 60NiTiZr alloy at temperature range of 300 to 600℃,it is found that with the increase of aging temperature,the hardness of the alloy first increases and then decreases,and reaches the highest hardness at 500℃.Further aging treatment of the water cooled 60NiTiZr alloy at 500℃ for different time shows that the hardness of the alloy reaches a peak value(61.7 HRC)after aging for 2 h,and a slow secondary hardening phenomenon also occurs at the later stage of aging.

关 键 词：60NiTi 热处理 Ni_(4)Ti_(3) H相 硬度 

分 类 号：TG146.1[一般工业技术—材料科学与工程]