Microstructure and properties of K4169 superalloy with nano polycrystalline reinforcement

Abstract

Abstract: A manual electric arc furnace andwater-cooled copper mould were used to prepare superalloy K4169. The microstructure of the alloy as-cast and standard heat treatment was examined by XRD, SEM, TEM, and the mechanical properties of the standard heat treated alloy were tested. The results show that as-cast K4169 alloy is amorphous-nanocrystalline material, the precipitation in grain is very fine and smaller than 10nm. The γ″ and γ′ phase are precipitated as nano polycrystalline after standard heat treatment the alloy. Because of the reinforcement by nano polycrystalline, the fracture strength σ_b of alloy can reach 1 203.91 MPa, and the yield strength σ_0.2 is 818.93 MPa, while the elongationδ is 16.8%, and the hardness reaches 112.4 HRB, and the tensile fracture characteristics conform to the ductile fracture mechanism.

Key words: K4169 Superalloy, microstructure, nano polycrystalline, mechanical properties, tensile fracture

CLC Number:

TG132.2

LI Ya-min, ZHOU Sheng-rui, HU Wei. Microstructure and properties of K4169 superalloy with nano polycrystalline reinforcement[J]. Journal of Lanzhou University of Technology, 2021, 47(4): 1-5.

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