Additive manufacturing (AM) has recently been receiving global attention. As an innovative alternative to existing manufacturing technologies, AM can produce three-dimensional objects from various materials. In the manufacturing industry, AM improves production cost, time, and quality in comparison to existing methods. In addition, AM is applied in the fabrication and production of objects in diverse fields. In particular, metal AM has been continuously commercialized in high value-added industries such as aerospace and health care by many research and development projects. However, the applicability of metal AM to the mold industry and other low value-added industries is limited because AM is not ad economical as current manufacturing technologies.
Therefore, this research proposes an effective solution to the problem. This study examines a method for using direct energy deposition and heterogeneous materials, an AM process for metals used to optimize the cooling channels and a key process in manufacturing hot stamping dies. The improvements in the cooling performances and uniform cooling were evaluated by a heat-flow analysis in a continuous process. In addition, a low-cost, high-functional, eco-friendly shearing mold manufacturing technology applicable to shearing of 1.5 GPa-class hot stamping parts was studied.
To this end, first, a specialized design technology was developed that applies the additive processing technology only to the functional part by dividing the functional part and the non-functional part. Second, we developed metal powders for hot and cold mold steels for additive manufacturing that can be applied to functional parts. Third, the evaluation of the mechanical properties of the developed metal powder materials according to the AM process conditions and a method of reducing residual stress that occurs during large-area AM processing of high-hardness materials are presented.
Finally, the developed technology is applied to the molding and shearing molds of hot stamping parts, and through test molding under semi-mass production conditions, through evaluation of cooling performance and lifespan and the possibility of commercialization was discussed.
When manufacturing a hot stamping mold using the technology proposed in this paper, the cooling performance can be dramatically improved by applying a uniform cooling channel. In addition, 1.5GPa class hot stamping parts are conventionally Although it relies on the laser shearing process, the efficient application of the material is possible when the developed shear mold manufacturing technology is applied, and the heat treatment process can be deleted from the mold manufacturing process. As a result, it is possible to secure a mold manufacturing technology with a low cost and short delivery time compared to the conventional shear mold manufacturing technology. In addition, it has excellent characteristics in terms of maintenance during mass production.
The developed technology can be applied to various similar fields such as injection molds and die casting molds, and is a national technology in the mold industry and 3D printing industry in the future and it will contribute to securing competitiveness.