Numerical simulation of the three-dimensional temperature field in laser cladding forming process

Laser cladding forming (LCF) is a new developed advanced manufacturing technology integrating rapid prototyping manufacturing and laser cladding surface modification. Since three dimensional near-net-shape metal components can be directly manufactured without dies, it has an extensive application prospect. Three-dimensional finite element model of powder-delivery transient temperature fields in LCF has been set up and numerical simulation has been carried out with parametric programming methods. Through the simulation, the temperature-time history curves, temperature field distribution, cooling rate and the temperature gradient of the laser cladding forming process have been obtained. The influences of laser power and scanning speed on the temperature gradient and cooling rate of the cladding layers have been studied, which provided a theoretical basis for the explanation of microstructure forming mechanism, cracking sensitivity and parameter selection. At the same time, LCF experiments have been conducted with parameters obtained from the simulation, microstructure of the cladding layers have been analyzed combining with the results of numerical simulation. Defect free laser cladding forming components with fine and homogeneous microstructure have been obtained with optimized parameters.