| On the surface of Crl2MoV mould steel, the powder layers of PHNi-60A nickel-based alloy and PHNi-60A plus 25 percent tungsten carbide have been produced with thermal spray. Then, the laser cladding experiments of single lane and continuous lapping lanes have been carried out on the powder layers with various technological parameters, which aims at exploring the effects of technological parameters on the cladding depths, the distribution of surface microhardness and its cause, the enhancement of the surface wear-resistance, the variation of the microstructures and the surface state of cracking and its cause. The results demonstrate that: (1) the surface hardness can be increased to some extend with its peak occurring in the subsurface, the additional tungsten carbide exerts little effect on the hardness improvement; (2) the wear-resistance of the laser cladding layer can be enforced by 1.91-4.24 times; (3) the surface microstructures consist of eutectics with planars and dentrites, with several metallic particles distributing in the interdentrites; (4) the cracks yielding can not be prevented by reducing the powder depths, preheating the materials before cladding and aging after laser treatment, but the quality and toughness of cladding surfaces can be improved obviously.
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