变形热处理对Ti45Zr20Nb15V(10-x)Al10Mox难熔高熵合金组织与性能的影响
Effect of deformation heat treatment on microstructure and properties of Ti45Zr20Nb15V(10-x)Al10Mox refractory high entropy alloy
李正龙 1庞景宇 2汤广全 2程陆凡 2张财伟 2侯星宇 2李文 1张海峰1
作者信息
- 1. 沈阳理工大学材料科学与工程学院,辽宁沈阳 110159;中国科学院金属研究所师昌绪先进材料研究中心,辽宁沈阳 110016
- 2. 中国科学院金属研究所师昌绪先进材料研究中心,辽宁沈阳 110016
- 折叠
摘要
向Ti45Zr20Nb15V10Al10难熔高熵合金基体中添加微量Mo元素,制备Ti45Zr20Nb15V(10-x)Al10Mox(x=0,0.5,1.0)难熔高熵合金,并对其进行变形热处理以改善其应变硬化能力和提高塑性.利用X射线衍射仪、场发射扫描电镜和万能力学试验机等探究了铸态及冷轧变形(变形量80％)后经600 ℃ ×5 h退火+800 ℃ ×1 h退火试样的微观结构及力学性能.结果表明,铸态合金为单相BCC结构,添加Mo元素后屈服强度提高,断裂延伸率保持在10％左右.经冷轧退火后,合金为BCC+Al3Zr4双相结构,大量近似球形的纳米级Al3Zr4相在晶界及晶界附近析出,使合金从应变软化转变为应变硬化,合金屈服强度保持在1100 MPa,断裂延伸率明显提升.Mo含量为0.5％时,冷轧退火后的合金断裂延伸率从铸态时的9.9％提升至16.9％,具有优异的强塑性匹配,且密度仅为5.638 g/cm3.
Abstract
Ti45Zr20Nb15V(10-x)Al10Mox(x=0,0.5,1.0)refractory high entropy alloy was prepared by adding trace amounts of Mo element to the Ti45Zr20Nb15V10Al10 refractory high entropy alloy matrix,which strain hardening ability and plasticity were improved by deformation heat treatment.Microstructure and mechanical properties of the as-cast specimen and cold-rolled(deformation of 80％)and annealed(600℃× 5 h and 800 ℃ for 1 h)specimen were investigated using X-ray diffractometer,field emission scanning electron microscope,and universal mechanical testing machine.The test results show that the as-cast alloy has a single-phase BCC structure,and the addition of Mo element increases the yield strength and maintains a fracture elongation of about 10％.After cold rolling and annealing,the microstructure of the alloy becomes BCC+Al3Zr4 dual phase with a large amount of approximately spherical nanoscale Al3Zr4 particles precipitated at and near grain boundaries,causing the alloy to transition from strain softening to strain hardening,and the yield strength of the alloy is maintained at 1100 MPa,while the fracture elongation is significantly improved.When the Mo content is 0.5％,the fracture elongation of the alloy after cold rolling annealing increases from 9.9％in as-cast state to 16.9％,exhibiting excellent strength plasticity matching and a density of only 5.638 g/cm3.
关键词
难熔高熵合金/变形热处理/应变硬化/组织/拉伸性能Key words
refractory high entropy alloy/deformation heat treatment/strain hardening/microstructure/tensile properties引用本文复制引用
基金项目
辽宁省自然科学基金(2023-BS-012)
中国科学院金属研究所创新基金(2023-PY16)
出版年
2024
NETL
NSTL
万方数据