DEGRADATION BEHAVIOR AND MATERIAL PROPERTIES OF PA12-PLASTIC POWDERS PROCESSED BY POWDER BASED ADDITIVE MANUFACTURING TECHNOLOGIES

摘要

Selective mask and laser sintering are powder based, additive manufacturing technologies, which allow the production of complex parts layer-by-layer. Due to the high building chamber temperature during processing, a physical and chemical degradation of the used plastic powder occurs. To reuse the unmolten material and to realize reproducible part properties it is necessary to refresh the partcake powder and establish constant powder properties. In this publication PA12-powders are conditioned in a model experiment at building chamber temperatures for different periods. Process relevant material properties like phase transition temperatures or melt viscosity are analyzed. Also the influence of material pretreatment on resulting material and mechanical part properties by the use of degradated powder are investigated.