Solvent debinding kinetics and sintered properties of injection moulded 316L stainless steel powder

Abstract

A stainless steel (316L) powder having a median particle size of similar to 25 mu m was injection moulded using binders composed of polyethylene glycols (PEG) and polymethylmethacrylate (PMMA). The PEG content was leached in water and debinding kinetics studied as a function temperature. At 40 degrees C, the removal of PEG was controlled by dissolution of the polymer in water and by diffusion of water and PEG for leaching time 60 min, respectively. Water soluble PEG was completely removed within 180 min and the diffusion mechanism controlled the de-binding process at 60 and 80 degrees C. Sintered properties improved with increased sintering temperature and time. The improvement in mechanical properties was less pronounced for a longer soaking time owing to more grain coarsening.