Influence of sintering temperature and atmosphere on densification behaviour and microstructure of the H13 tool steel

To produce dense parts using the fused filament fabrication process, a sintering step is required. After debinding, sintering must be perfectly controlled to obtain functional parts by controlling sintering conditions such as temperature and atmosphere. The aim of this work is to propose a detailed study of the densification during sintering of a H13 steel, as a function of both temperature and the nature of the atmosphere, linking it to the final relative density and microstructure. To this end, complementary in situ and ex situ characterisation methods were used to study the densification evolution at the filamentary scale. The influence of environmental sintering conditions was also discussed in terms of porosity dynamics and measured mechanical properties. The results provide a better understanding of sintering and in particular of the operating conditions to be used to obtain functional parts.