Simulation of the physico-chemical interaction of molten substrate with powder being deposited during laser cladding process.

The problems of mathematical model construction for physico-chemical and heat and mass transfer processes are discussed for additive laser technologies in case, when substrate and powder materials can form chemical compound. A description of exothermic reactions in nickel particles fed to the melt during laser cladding or alloying is proposed.

Numerical modelling of laser cladding on aluminum substrate with nickel powder is carried out in case of small powder injection rate. Growth of inter-metallic layer on Ni particle surface is simulated in conjunction with the laser induced thermocapillary convection and melting/crystallization of Al substrate. Laser beam scan surface of substrate with constant velocity.

Reaction rate highly depends on temperature conditions in current particle location in a melt pool so special consideration is given to the particle movement trajectory in molten substrate flow and particle distribution in the beam trace obtained after melt crystallization.

Simulation was carried out on code developed by author under OpenFOAM framework for continuum mechanics calculations.