Study on direct laser fabrication of Nd:YAG

Recently, the study on the direct laser fabrication by CO2 laser is more than that by Nd: YAG laser. The primary goal of this research is to study technics and structure performance of metal component of laser rapid prototyping based on Nd: YAG laser and coaxial powder feeder. The experimental equipments consist of ROFIN 1.1KW YAG laser, a 3-axis CNC table, a coaxial powder nozzle and a powder recycler. Firstly, the single-track cladding experiment was conducted; the effect of laser power, scan velocity and Z-axis increment on the single-track cladding shape was studied with different processing parameters. Secondly, some tensile samples, which were built by direct laser fabrication (DLF) using the best processing parameters, were analyzed by tensile experiment, SEM and EDS. The effect of Nd: YAG laser rapid prototyping technology on the structure and performance was studied and compared with the results of CO2 laser fabrication on the approximate condition. Lastly, some molding samples built by Nd: YAG laser were shown in the paper. In conclusion, the technics parameters have large effect on the molding result; the key technology of laser rapid prototyping is searching the best process parameters. The tensile samples built by Nd: YAG laser have the features of high intensity, fine crystalline grains and orientated solidification structure; moreover, the orientations of laser scanning have influence on tensile performance. Compared with the CO2 laser rapid prototyping, its tensile strength is higher and its plasticity is lower.