Effect of Substrate Preheating, Remelting, In-situ Presintering on Crack Formation of Ti-47Al-2Cr-2Nb Fabricated by Selective Laser Melting

Abstract:

The methods of substrate preheating, remelting and in-situ presintering were proposed to fabricate Ti-47Al-2Cr-2Nb by selective laser melting (SLM). The effects of these approaches on the formation of cracks and surface quality were investigated. The results indicate that substrate preheating, remelting and in-situ presintering powder can reduce the formation of cracks to a certain extent, and the density is increased by 1.71%~4.34%. Remelting contributes to improvement of the surface quality but greatly reduces the productivity. In addition, the combination of substrate preheating and in-situ presintering can effectively prevent the occurrence of cracks, and the density is over 99%.