| 摘要: | 金屬陶瓷具有未來潛在應用的高機械性能材料，目前為止，通過選擇性雷射熔融 (SLM) 製造的非原位金屬陶瓷種類較少。在本研究中，主要用500 W連續式雷射之選擇性雷射熔融TiN-SUS 420金屬陶瓷樣品，以同步方式進行其拋光，首先由不同雷射功率對TiN-SUS 420(50 wt%-50 wt%)觀察，選擇較佳的參數進行不同 TiN 含量燒結，觀察其緻密化行為、微觀結構、硬度、破裂韌性。結果表明，添加TiN對密度有很大影響，這主要是其對粉末的雷射吸收率和液態金屬的潤濕性有影響，不僅如此，粉體粒徑也有相對關係。隨著雷射功率的增加，TiN的擴散行為變得更強，金屬陶瓷的緻密化得到改善，對於TiN-SUS 420(50 wt%-50 wt%)可獲得最大相對密度達到90.74%。通過SEM、XRD結果研究了TiN顆粒的分佈和固溶體。優化後的複合材料達到823.67 HV1的高硬度，比選擇性雷射熔融製造的 (SLMed) SUS 420相對來得高，一般SUS 420的硬度為250 HV附近。再藉由雷射拋光技術，使材料表面開始熔化，由於表面張力的多向作用下，材料表面的“波峰”與“波谷”重新定位。然後通過能量密度的調整下，實現不同的表面粗糙度、微觀結構與緻密性等機械性質的影響，分別和SLMed樣品進行機械性質比較，並以材料的特性配合雷射加工後的結構，解決後加工等相關問題，不僅減少繁雜工序，還降低勞動成本。;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. |
