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

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 and > 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.