Numerical and experimental investigations of thermal debining process in powder injection molding.
Khoong, Ling Eng.
Date of Issue2006
School of Mechanical and Aerospace Engineering
Powder injection molding (PIM) is an important net-shape manufacturing process and has received much attention. This process is capable of producing complicated metal and ceramic products in mass volume with low production cost. PIM involves mixing, molding, debinding, and sintering processes. Debinding process is one of the most critical steps. This process consumes a major part of the processing time. And yet, attempts to speed up this process often results in failure of PIM components, like distortion, contamination, and cracking. Among various types of debinding methods, thermal debinding is a common methodology to remove binders from PIM components. During thermal debinding, binders are heated thermally, melted into liquid, and evaporate into vapor. The overall removal of binder involves evaporation, thermal degradation of polymer, transports of liquid and gas phases, and heat transfer in a PIM compact. A successful theoretical modeling and a comprehensive experimental observation provide the potential for optimization of the debinding process to shorten the processing time without causing defects on the PIM products.
Nanyang Technological University