Microstructural and Mechanical Properties of Two Fe-Based Alloys Prepared by Laser Cladding

According to the actual production demands of local metallurgical enterprises, two kinds of Fe-based alloy powders, A and B, were designed. Their elemental compositions were C, Mn, Si, Cr, V, Ni, Fe for A; and C, Mn, Si, Cr, Mo, Al, Ni, Fe for B. Then two kinds of Fe-based alloy layers were prepared on the surface of a 40CrNiMoA steel substrate by laser cladding to form Clad A and Clad B. The microhardness and tensile properties of the clad layers were tested. The friction and wear properties were evaluated and the surface morphology of the samples after wear was observed and characterized. The results show that the laser clad Fe-based alloy powders form a good metallurgical bond with the substrate matrix and without observable defects such as cracks, porosity. The microhardness of the Clad A and Clad B reach 348 and 310 HV0.2, respectively; the tensile strengths are 960 to 1000 MPa and 830 to 870 MPa, respectively; the yield strengths are 780 to 820 MPa and 490 to 520 MPa, respectively; the elongations after fracture are 10 to 12% and 24 to 26%, respectively; the fluctuation ranges of friction coefficient are 0.30 to 0.50 and 0.35 to 0.70, respectively; and the wear amounts are 0.9 and 1.6 mg, respectively. Clad A exhibits a higher hardness and strength than Clad B, while the plasticity of Clad A is inferior to Clad B.