激光熔覆沉积成形NbMoTaTi难熔高熵合金的组织与强度研究

摘要

通过激光熔覆沉积技术制备应用于航空航天工业的NbMoTaTi难熔高熵合金材料,通过X射线衍射判断出成形的合金晶体结构为体心立方的单相固溶体结构.高熵合金晶粒尺寸大多在2~12μm之间;平均显微硬度为397.6HV,室温抗压强度为1301.83MPa,1000℃高温抗压强度只达到347.28MPa,其原因可能与激光熔覆沉积成形NbMoTaTi高熵合金的过程中产生的气孔、未熔化/不完全熔化的Ta粉末粒子和裂纹有关,需进一步研究.%The paper is to prepare the refractory high entropy alloy, NbMoTaTi, in aerospace industry by laser clad-ding deposition technology. The crystal structure of the alloy is single phase solid solution structure of BCC analyzed by X-ray diffraction. The grain size of the NbMoTaTi high entropy alloy is mostly between 2-12μm. The average micro-hardness is 397.6HV and the room temperature compression strength is 1301.83MPa. The high temperature compression strength under 1000℃ is only 347.28MPa because of the defects such as pores, without /incomplete melting Ta powder particles and cracks generated during the forming process of NbMoTaTi high entropy alloys, so further research is needed.