Effect of scanning speed on microstructure and properties of 30Cr3Ni2 alloy steel prepared by direct laser deposition

The 30Cr3Ni2 alloy steel samples were prepared by direct laser deposition (DLD) technology with different scanning speeds. The microstructure and mechanical properties of the samples were studied by metallographic microscope, scanning electron microscopy, energy dispersive spectroscopy, microhardness tester and electronic universal material tester. The results show that when the laser power was 2500W and the scanning speed was 10mm/s, the fabricated sample mainly consisted of granular bainite(GB) with (Fe,Cr)₇C₃ carbide. The average hardness value was 341HV, the tensile strength was 875Mpa, the yield strength was 867Mpa, and the elongation was 3.9%. This study provides the basis for the further development of alloy steel produced by DLD.