摘要
通过在变形温度870~1030℃、初始应变速率10-3s-1条件下的单向拉伸试验,研究了不同氢含量对Ti2Al Nb基合金超塑性变形行为的影响。结果表明,置氢能显著提高Ti2Al Nb基合金的伸长率,降低峰值应力;在910℃,置氢0.18%的合金峰值应力为142 MPa,伸长率为238%,相比未置氢合金峰值应力降低了22%,伸长率提高了71%。这主要是由于置氢促进了Ti2Al Nb基合金的晶粒细化,而且促进了B2相和硬脆α2相向O相的转变。H元素能促进α2相在超塑性变形过程中发生相分解反应,硬脆相α2相分解为B2相与O相,降低了Ti2AlNb基合金超塑性变形的流动应力。
The effects of different hydrogen contents on the superplastic deformation behavior of Ti2AlNb-based alloy were investigated by uniaxial tensile tests at deformation temperature of 870-1030℃and initial strain rate of 10-3 s-1.The results show that hydrogen treatment can significantly increase the elongation of Ti2AlNb-based alloy and reduce the peak stress.At 910℃,the peak stress and elongation of the hydrogenated alloy with 0.18%H are 142 MPa and 238%,respectively.Compared with unhydrogenated alloy,the peak stress is reduced by 22%while the elongation is increased by 71%.This is mainly due to the grain refinement of Ti2AlNb-based alloy and the transformation of B2 phase and hard brittle phaseα2 phase to O phase by hydrogenation treatment.Hydrogen can promote the decomposition reaction ofα2 phase during superplastic deformation process,andα2 phase decomposes into B2 phase and O phase,which reduces the flow stress of Ti2AlNb-based alloy in superplastic deformation.
作者
贾国朋
万李
贾春莉
刘贺
李细锋
叶福田
JIA Guo-peng;WAN Li;JIA Chun-li;LIU He;LI Xi-feng;YE Fu-tian(Institute of Forming Technology and Equipment,School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200030,China;Capital Aerospace Machinery Company,Beijing 100076,China;Dongguan Hengli Die&Mold Technological Industry Development Co.,Ltd.,Dongguan 523460,China)
出处
《塑性工程学报》
CAS
CSCD
北大核心
2019年第6期235-242,共8页
Journal of Plasticity Engineering
基金
一院高校联合创新基金(CALT基金)
关键词
TI2ALNB基合金
超塑性变形
置氢处理
O相
Ti2AlNb-based alloy
superplastic deformation
hydrogenation treatment
O phase
