Optimization of direct metal printing process parameters for plastic injection mold with both gas permeability and mechanical properties using design of experiments approach

Abstract

Direct metal laser sintering (DMLS) technology plays an important role in molds or dies industry. The distinct feature of the metal components, molds, or dies fabricated by DMLS possesses gas permeability. However, the mechanical properties of the fabricated molds were influenced by degree of gas permeability. In this study, the design of experiments (DOE) approach was employed to optimize the DMLS process parameters for fabricating plastic injection mold with better gas permeability and mechanical properties. It was found that the optimal DMLS process parameters for fabricating plastic injection molds with better mechanical properties and gas permeability are layer thickness of 30 μm, hatching space of 141 μm, scanning speed of 220 mm/s, and laser power of 50 W. The most important DMLS process parameter affecting the mechanical properties and gas permeability is the layer thickness, followed by the hatching space. The gas venting mechanism for molds fabricated by DMLS has been demonstrated.