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

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.