Question

How are engineering ceramics densified? Explain the driving force for densification.

Answer 1

ceramics are densified from powders by applying heat—a process known as sintering. In this process, matter from adjacent particles, under the influence of heat and pressure, diffuses to “neck” regions that grow between the particles and ultimately bond the particles together.

The driving force for densification is the change in free energy from the decrease in surface area and lowering of the surface free energy by the replacement of solid-vapor interfaces. It forms new but lower-energy solid-solid interfaces with a total decrease in free energy occurrence