次生α相含量对TC18钛合金动态压缩性能和绝热剪切敏感性的影响  

Influence of volume fraction of secondary α phase on dynamic compression properties and adiabatic shear sensitivity of TC18 titanium alloy

作　　者：郭小汝 张俊喜 易湘斌[2] 陈百明 李宝栋[2] 徐创文[2] GUO Xiao-ru;ZHANG Jun-xi;YI Xiang-bin;CHEN Bai-ming;LI Bao-dong;XU Chuang-wen(School of Material Engineering,Lanzhou Institute of Technology,Lanzhou 730050,China;Key Laboratory of Green Cutting Technology and Application in Gansu Province,Lanzhou Institute of Technology,Lanzhou 730050,China)

机构地区：[1]兰州工业学院材料工程学院,甘肃兰州730050 [2]兰州工业学院,绿色切削加工技术及应用甘肃省重点实验室,甘肃兰州730050

出　　处：《材料热处理学报》2020年第10期24-30,共7页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(51865026);甘肃省自然基金(18JR3RA229);兰州工业学院青年科技基金(18K014)。

摘　　要：研究了固溶温度对TC18钛合金中次生α相含量的影响,并利用分离式霍普金森压杆,在高应变率(1000~3000 s-1)条件下,进一步研究了次生α相含量对TC18钛合金动态压缩性能及绝热剪切敏感性的影响。结果表明,随着固溶温度的升高,次生α相的含量由约46%增加到约71%;高应变率下,随着次生α相含量升高,TC18钛合金流变应力增大、塑性应变减小、绝热敏感性增大。分析表明,引起这种变化的主要原因是在固溶过程中,随着温度的升高,亚稳β相生成量增加,使得后续时效过程中的交错分布次生α相析出量增加,从而提高了合金强度,塑性降低。在动态压缩条件下,近网篮组织的TC18钛合金随应变率的提高,绝热剪切敏感性增加。Effect of solid solution temperature on the content of secondary α phase of TC18 titanium alloy was investigated, and the effect of secondary α phase content on dynamic compression properties and adiabatic shear sensitivity of the TC18 titanium alloy was investigated by using the split Hopkinson pressure bar(SHPB) under the condition of high strain rate(1000-3000 s-1). The results show that the content of secondary α phase of the TC18 titanium alloy increases from about 46% to about 71% with the increase of solid solution temperature. At high strain rate, with the increase of secondary α phase content, the flow stress of the TC18 titanium alloy increases, plastic strain decreases and adiabatic shear sensitivity increases. The analysis shows that the main reason for this change is that the amount of metastable β phase formation increases with the increase of temperature in the solid solution process, which leads to the amount of secondary α phase precipitation with staggered distribution in the subsequent aging process increase, thus increasing the alloy strength and reducing the plasticity. Under dynamic compression conditions, the adiabatic shear sensitivity of the TC18 titanium alloy with near-basket microstructure increases with the increase of strain rate.

关 键 词：TC18钛合金 动态压缩性能 剪切敏感性 次生α相 

分 类 号：TG146.2[一般工业技术—材料科学与工程]