Study Of Laser Cladding Technology Based On The Cr12MoV

The Cr12 MoV cold working die steel which is usually used in die and mould industry as the research object in this paper, the cladding experiments are done on the substrate surface by using fiber lasers and related auxiliary equipment, and explore the influence of different process parameters on the cladding layer macroscopic appearance, size and microstructure of cladding layer to determine the best process parameters, it can provide a certain basis for the actual repair and application of mould.Firstly, the finite element software is used for laser cladding temperature field simulation, by changing laser power and scanning speed to get the temperature field distribution characteristics which is under different power and scanning speed: molten pool presents the comet tail shape, the temperature gradient around the pool is large, the molten pool temperature is increase with the increase of power. The heating effects of molten pool that is far away from the substrate can be up to one third, temperature gradient is small. The changes of scanning speed for molten pool temperature variation are not obvious. The process parameters of reference range can be got: the scanning speed is 6mm/s-10mm/s, the laser power is 200W-1000 W.Then studying the effect of the two kinds of different heat treatment quenching and annealing matrix on the properties of cladding layer. The scanning speed and feeding amount are fixed and changing the laser power as a variable parameters, Ni60 A and 70% Ni60 A and+30% WC powder are clawed on substrate surface which is different in quenching and annealing heat treatment state. The performance index of cladding layer analysis of the test results shows that the cladding layer’s performance is not significantly different by choosing the same parameters and powder for laser cladding in different heat treatment states. The cladding layer is only related to the cladding process parameters and has no relation with heat treatment state. The laser cladding processing can be used in annealing matrix in the key position of the parts and components, which can achieve performance requirements and avoid quenching treatment of micro thermal deformation.Secondly, the cladding experiments is made on quenching state matrix surface by regarding Ni60 A powder as cladding powder, and by comparing the laser power and scanning speed of cladding layer macroscopic appearance and microscopic size and hardness of the cladding layer width and height in the influence of the optimal process parameters, scanning speed10mm/s, laser power200 W, delivering powder8 V is the optimum technological parameters. The result shows that the cladding layer is consisted of three parts, including the cladding region, combining with the zone and heat affected zone. Heat affected zone exists some black floccules. the microstructure of cladding region is mainly the cellular and dendrite crystal structure of the organization which is no obvious cracks and pores, the lower organization is bulky sparse and the upper organization is fine and evenly distributed, the white wavy appears between cladding and substrate, such combination can enhance the wear resistance of the cladding layer. At the same time, the experiment combined with simulation results of temperature field to verify the reliability of the temperature field simulation, the damaged area of Xing-cheng powder metallurgy factory stamping die grinding is repaired successfully.Finally, according to the characteristics of asymmetrical sheet, the cladding experiments is going on by choosing circumferential rotation, the axial line and spiral path and using the optimum process parameters in laser cladding, through making a contrasting of cladding layer related performance indicators to get the spiral path is the best optimal path, and making a further optimize for the process parameters through experimental analysis, the laser power 900 W, feeding voltage 14 V under the spiral path is the optimal process parameters. The lastly, the damaged area of LI-De shock absorber factory stamping die grinding is repaired successful by laser cladding.