The structure and properties of Inconel 718 superalloy powder prepared by vacuum induction melting gas atomization for laser direct metal deposition

Inconel 718 superalloy powder is one of the main materials for laser direct metal deposition aero parts, and the characteristics of alloy powder have an important impact on the microstructure and properties of the formed parts. In this paper, Inconel 718 superalloy powder for laser direct metal deposition was prepared by vacuum induction melting gas atomization. The results show that the degree of sphericity of the prepared alloy powder is 98% and the particle size distributed within the scope of 1–150 μm. The flowability is 15.2 s/50 g, the apparent density is 4.93 g cm⁻³, the rate of hollow sphere is 4%, the matrix phase of the alloy powder is γ phase and the strengthening phase consists of the main strengthening phase γ′, the auxiliary strengthening phase γ′ and a small amount of carbide MC. After laser forming, the microstructure is dense with few defects, the phase composition is consistent with the powder phase composition. The tensile strength of laser direct metal deposited samples is 822.3 MPa. The elongation is 12.8%, and the hardness is about 275 HV_0.2. The Inconel 718 superalloy powder prepared by VIGA has good powder characteristics and meets the requirements of alloy powder characteristics required for laser direct metal deposition. (paper)