분말 베드 융합과 직접 에너지 적층 공정을 혼합한 하이브리드 방식으로 제조된 금속 소재의 특성에 관한 연구

Abstract

With the development of additive manufacturing technology, the field of application has been gradually expanded, and the application is increasing in industries such as aerospace, defense, and automobile industry. Typically, PBF and DED processes, which are metal additive manufacturing technologies, are widely used. PBF is useful for producing complex shapes because it can implement high precision and surface quality. However, the production speed is relatively slow and there is a limit to the size of the product. DED has a much faster production rate, no product size restrictions, but relatively low precision and surface quality. Therefore, the hybrid process in which PBF and DED are combined aims to compensate for the disadvantages of each process and to maximize the advantages. This hybrid process will increase productivity and enable the production of products that cannot be manufactured by conventional manufacturing processes. In this study, we aim to establish basic data through comprehensive analysis of the surface characteristic, deposition characteristic, microstructure, and mechanical properties according to the building direction of the hybrid sample. DED deposition was performed on the substrate made of PBF to prepare a hybrid sample. Mechanical properties were different depending on the relative building directions of PBF and DED. In the tensile test, when the direction of the layer and the direction of the tensile load were parallel, the strength was higher than when they were vertical. However, in the impact test, the impact absorption energy was better when the direction of the layer was vertical to the impact direction than when it was parallel. It was confirmed that the mechanical properties of the hybrid product may vary depending on the relative building direction of PBF and DED and the load direction or type of load applied to the product. These results will be able to provide basic data when setting the building direction in product design.