Abstract: It is the chief difficulty of laser cladding metal-ceramics layer that cracks are liable to emerge. The processing technology and coating materials are studied to resolve the problem. Firstly, according to the calculating of temperature field distribution and analysis of thermal stress in the cladding procedure, it is considered that the scanning velocity of laser beam and initial temperature are the main technological factors of crack emergence. On the other hand, the gradient distribution of ceramic hard phase is carried out and transition layer is put in between cladding layer and substrate. The results of SEM and microhardness test show, the hardness changed smoothly from surface to substrate, coating layer is dense and free of cracks. !4
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