| dc.description.abstract | Cermets have potential applications as materials with high mechanical properties in the future. So far, there are few types of ex-situ cermets manufactured by selective laser melting (SLM). In this study, the selective laser of 500 W continuous fiber laser was mainly used to melt the TiN-SUS 420 cermet sample, and the polishing was performed in a synchronous manner. First, the TiN-SUS 420 (50 wt%- 50 wt%), select better parameters for sintering with different TiN content, and observe its densification behavior, microstructure, hardness, and fracture toughness. The results show that the addition of TiN has a great influence on the density, which is mainly because it has an influence on the laser absorption rate of the powder and the wettabil-ity of the liquid metal. Not only that, but also the particle size of the powder has a relative rela-tionship. With the increase of laser power, the diffusion behavior of TiN becomes stronger, and the densification of cermet is improved. For TiN-SUS 420 (50 wt%-50 wt%), the maximum relative density of 90.74% can be obtained. The distribution and solid solution of TiN particles were studied by SEM and XRD results. After optimized parameters, the composite material achieves a high hardness of 823.67 HV1, which is relatively higher than that of SUS 420 manufactured by SLMed. Generally, the hardness of SUS 420 is about 250 HV. With laser polishing technology, the surface of the material starts to melt. Due to the multi-directional action of surface tension, the ＂wave peaks＂ and ＂wave valleys＂ of the material will be automatically repositioned. Then, through the adjustment of energy density, the effects of different mechanical properties such as surface roughness, microstructure and compactness are realized. The mechanical properties of the laser polished SLMed samples were compared with the SLMed samples, and the characteristics of the materials are matched with the structure after laser processing to solve the problem. Related issues such as post-processing not only reduce complicated procedures, but also reduce labor costs. | en_US |