Wear of directed energy deposited H13 steel as a function of its graded microstructure

The processing parameters of directed energy deposition (DED) H13 steel were first optimized by analyzing their effects on the molten pool. Then, the microstructure, hardness and wear behavior of DED H13 steels and their correlations were investigated in detail. The wear resistances at the matrix, bottom, and top of the DED H13 steel were experimentally determined. The dominant wear modes at the top and bottom are oxidative wear and delamination, and those at the matrix are abrasion. According to the microstructure and finite element analyses, the graded structure induced by intrinsic heat treatment during the DED process controls the microstructure evolution and hence the wear performance.