Sintering

A typically solid state process where adjacent surfaces of particles in a mass of powder, or a green compact, become bonded by heating. Sintering increases strength and produces densification. In addition to bonding, sintering decreases the pore volume and leads to rounding of pores and the formation of grain boundaries where particles are in contact. Recrystallization often occurs in PM. Liquid phase sintering is similar, except one of the components is present as a liquid during part of the process.