Sintering Behaviour of 3d Printed 17-4PH Stainless Steel

Abstract

The main aim of the research work is to investigate the sintering behavior and its impact on the material properties of 3D printed 17-4PH stainless steel. The samples were manufactured by the Atomic Diffusion Additive Manufacturing technique, the Metal X system. Cooling holes were printed with the sample in different build orientations giving an overview of the printability and accuracy of the atomic diffusion additive manufacturing (ADAM) technique. Samples were processed by washing, thermal de-binding, and sintering to produce a final solid metal part. Pre-sintered parts, after washing, were tested for chemical composition, roughness, particle size analysis, density, Energy Dispersive X-ray spectroscopy, and microstructure analysis using Scanning electron microscopy (SEM) to understand the material properties. Post-sintered samples were tested for the same tests to understand the sintering impact. A unique conceptual approach and statistical analysis are included in this research. To understand the thermal de-binding and sintering kinetics Differential Scanning Calorimetry (DSC) and Dilatometry (DIL) tests were performed. DSC results gave details about the thermal de-binding and binder information. Dilatometry (DIL) results showed shrinkage over the temperature profile, and significant changes in shrinkages were found above 1250 °C. The results gave an overview of the sintering kinetics and sintering impact of 3D printed 17-4PH stainless steel. This helps decide the optimized thermal debinding and sintering profile to achieve high dense material. It should be noted that this is the first-ever study investigating in detail thermal de-binding and sintering kinetics and its impact on the material properties according to the ADAM technique.