Experiments and modelling for weld shape in keyhole laser welding

In this paper,it is found that there existed a little fluctuation in the weld depth at the frequency of 30～40Hz,when a mild steel had been welding by a laser beam.The laser welding is a very complex procedure,including absorption of the light energy,generation of plasma,heat conduction,et cetera.So we consider a relative simple model to simulate the laser energy Fresnel-absorption of the keyhole wall and stationery temperature field of the melting cell,based on the heat conduction of the workpiece.Finally,the analytical solution can be achieved and the simulations are consistent with experimental results.