The conductive oxide impact on Aluminum alloy of YAG pulse laser welding
Few articles are reported about conductive oxide impacting on Aluminum alloy of Nd: YAG pulse laser welding at present. Therefore, this paper takes one typical Aluminum alloy as laser welding samples. Through SEM (scanning electron microscope) microscopic analysis and contrast, the comparative study between on with and without surface conductive oxidation impacting on laser welding samples have been conducted. The results show that the laser welding process parameters are needed, but the conductive oxide will bring no destructive effect on laser welding. Accordingly for this reason, it is thought that the conductive oxide will not bring substantial effect on Aluminum alloy of Nd: YAG pulse laser welding.
APPLICATION AND DEVELOPMENT OF LASER-PROCESSING TECHNOLOGY
The applied fields of laser-processing technology is introduced in broad outline.Some typical applications are discussed,such as laser drilling and cutting,laser welding,changed function fechnology on surface,laser carving,milling and texturing,laser deposit,quich-formed technology,laser marking and mark carving.Meanwhile,the present situation of the laser processing industry at home and abroad is introduced.
A numerical model for deep penetration welding processes
The general features of a numerical model, and of its extensions, for calculating the temperature and fluid velocity field in a three-dimensional workpiece undergoing deep penetration laser beam welding are described. In the current model, the deposition of power from the beam is represented by time-dependent boundary conditions on the equations of energy and momentum transfer. These boundary conditions are specified at each timestep on a surface whose configuration can change with time and upon which energy is deposited according to a specified power distribution. This model also includes the effects of the buoy-ancy force on the melt pool and of the surface tension gradient on the surface of the fluid. The coupled equations of energy, momentum transfer, and continuity combined with the time-dependent boundary conditions representing the keyhole and the moving boundaries of the workpiece are solved by using a specific implementation of the SIMPLE algorithm. The important features of the numerical methods used in the model are discussed. Isotherms and convection patterns calculated using the current model are presented, and their significance for predicting weldment properties is discussed. A significant result of the simulations is that they demonstrate the overwhelming influence of the keyhole vapor/liquid inter-face on fluid convection and conduction in deep penetration welding.