Effect of Heat Treatment Schedules and Glass Powder Particle Size on Glass Infiltration in Porous Alumina Preforms

Abstract

Glass infiltrated alumina is one of the popular materials for fabrication of dental prostheses. Achieving complete and uniform glass infiltration is important to achieve desired properties in dental prostheses. This study examined the role of various factors on glass infiltration in sintered porous alumina preforms (porosity ~ 27%). Observations on infiltration in porous alumina samples at a heating rate of 3°C/min at 1100°C for 2 h showed residual glass on the surfaces of the samples indicating incomplete infiltration. Rapid heating of the samples to the peak infiltration temperature by introducing the samples into a preheated furnace resulted in complete infiltration of glass into the samples in <90 min. In addition to heating rate during infiltration, influence of soaking duration and the particle size of glass powder on glass infiltration were also examined.