TheSinteringpressure-assisted sintering densification ratePressure-assisted sintering is significantly enhanced by applying mechanical pressures much higher than the sintering stress in pressure-assisted sintering, including hot isostatic pressing, hot pressing, spark plasma sintering, and sinter forging. Pressure-assisted sintering produces dense materials with smaller grain sizes and superior properties in a shorter time and at lower sintering temperatures. The deformation mechanisms involved in pressure-assisted sintering include diffusional creep, dislocation creep, and plastic yielding. At high stresses, porous materials deform through dislocation creep, resulting in a non-Newtonian constitutive equation. The large voids and defects in powder compacts are deformed and eliminated by mechanical stress.