Experimental Study on the Microstructure of FeCoNiCr High-Entropy Alloys by Selective Laser Melting

doi:10.12068/j.issn.1005-3026.2023.04.011

Abstract

Abstract: The thermal analysis theory of selective laser melting was introduced， and FeCoNiCrAl_0.5 and FeCoNiCrAl_0.8 high-entropy alloys were prepared by selective laser melting. The effects of powder particle size， element content and process parameters on the microstructure of high-entropy alloys by selective laser melting were analyzed. The results showed that with the increase of laser power， the proportion of equiaxed crystals at the top of the specimen becomes smaller， while the proportion of dendrites in the bottom of the specimen becomes larger and larger. With the increase of scanning speed， the size and width of dendrite in the bottom of high-entropy alloy specimens decrease gradually. The effect of lap ratio on the microstructure of high-entropy alloys is small. It was found that the high-entropy alloy specimens have some defects such as cracks， dents and pores.

Key words: selective laser melting; high-entropy alloy; microstructure; defect

CLC Number:

TH161

WEN Xue-long， WANG Cheng-bao， LIU Wen-bo， REN Hai-yang. Experimental Study on the Microstructure of FeCoNiCr High-Entropy Alloys by Selective Laser Melting[J]. Journal of Northeastern University(Natural Science), 2023, 44(4): 536-543.

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