DESIGNING A MODEL FOR POLYMERIC BINDER DEGRADATION, VOLATILIZATION AND DIFFUSION THROUGH POROUS MEDIA

摘要

The incorporation of a temporary polymeric binder into the processing of ceramic or metal powders is a common practice used to make a green body with sufficient strength to permit processing prior to sintering. Binders are particularly important for 3D printing and other additive manufacturing processes. However, the binder's removal is essential for the structural integrity of the final product; any remaining binder is a defect which can, for example, compromise the mechanical strength. A better understanding of the binder's degradation, volatilization, and diffusive and convective flows out of the porous green body can be obtained through the development of a model that combines easy-to-obtain empirical parameters with kinetics, thermodynamics and transport phenomena. This will enable the development of an optimal heating profile that minimizes the residual binder at the same time as maximizing the removal efficiency.