Melt pool shape and dilution of laser cladding with wire feeding

Dilution is an important factor to influence the properties or laser cladding. To get high quality clad layer, low dilution is required. During laser cladding, heat will accumulate near the melt pool before quasi-steady state is reached. So dilution will become larger and larger. In this paper the melt pool of laser cladding is modeled by time-dependent finite element method (FEM). Adaptive mesh is used to adapt the mesh to the melt pool shape, which changes during cladding. Relative reference frames are used. The reference frames are first attached to the laser power during cladding period and then attached to the workpiece at a certain cladding time. Dilutions and melt pool shapes at different cladding times are calculated by a two-dimensional FEM model. Experiment of laser cladding with wire feeding is done. The influences of cladding time and cladding speed on dilution and melt pool shape are checked. The FEM results coincide with the experimental results. (C) 2000 Elsevier Science S.A. All rights reserved.