ABSTRACT
This chapter covers two DLC technologies in the sustainable green manufacturing toward the circular society. The used DLC films and their buffer layers are removed from the substrates by the high-density oxygen plasma ashing process to reuse the original substrate materials. In particular, the specially designed tool and die substrates must be recycled to preserve their value in tooling by the perfect oxygen plasma ashing with minimum damage to them. The second DLC technology is a DLC-die materialization. Hard DLC coating with low surface roughness is suitable as a die material to make micro-/nano-imprinting for functional decoration of metals and alloys. A micro-/nanotexture is machined into the CVD-DLC coated tool steel punch by using the femtosecond laser processing. The CNC-stamping system is employed to imprint these textures into the aluminum plate. In parallel with this geometric imprinting, the optically grated punch surface is duplicated onto the aluminum plate surface. The optical grating capacity is also proved to the aluminum parts by this imprinting. Once this designed die is unnecessary for usage in the market, the original punch substrate can be recycled by the first technology. The waste in this change of punch is absolutely minimized by using this second DLC-die technology.
