Investigations On The Surface Quality Of Metal Parts Produced Via Gel Casting

Developments in the sinter-based additive manufacturing (AM) of metal components are progressing rapidly and the quality of the AM parts is steadily increasing. However, there are always process-related limitations with regard to surface roughness, which may make post-processing necessary. Within this context, the hybrid process chain of gel casting with AM molds can offer advantages, as the surface quality of the mold is transferred to the metal part and smoothing of the polymer mold is possible without effort. In this study, surface roughness was evaluated using different mold qualities. The surfaces in the green and sintered states were investigated and related to the mold surface quality. It is found that the surface roughness values Ra and Rz can range below the mean particle size of the powder used, which saves post-processing of the metal component in relevant applications.