时效热处理对EB-PVD镍基合金薄板组织与力学性能的影响

Effect of Aging Heat Treatment on Microstructure and Mechanical Properties of EB-PVD Ni-Based Alloy Sheet

摘要:

采用电子束物理气相沉积方法（EB-PVD）成功制备了直径为1000 mm，厚度为0.10~0.13 mm的镍基合金薄板。利用光学显微镜（OM）、扫描电子显微镜（SEM）和透射电子显微镜（TEM）等测试方法，对时效热处理前后试样形貌、析出相组成、高温拉伸性能进行了研究。结果表明，镍基合金薄板材料时效热处理后，晶粒长大，随时效时间延长，晶粒长大速率明显降低。在时效过程中，有细小碳化物颗粒在晶界析出，衍射花样分析表明，碳化物为FCC结构的(Cr,Fe)23C6。时效热处理后，镍基合金薄板材料高温拉伸性能有了很大提高，延伸率有一定的降低。

Abstract:

Ni-based alloy sheet with the diameter of Ф1000 mm and thickness of 0.10-0.13 mm was fabricated by electron beam physical vapor deposition (EB-PVD). Microstructure, precipitated carbide composition and tensile strength were studied for the samples before and after aging heat treatment by optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). The results show that crystal grains grow up after aging heat treatment; the growth speed slows down evidently with aging time prolonging. Small carbide particles precipitate at the grain boundary during aging, which are (Cr, Fe)23C6 with fcc structure by diffraction pattern analysis. The high-temperature tensile strength of the aged sample increases obviously while the elongation decreases to some extent.