A method and apparatus for powder compaction using high velocity adiabatic impact. A quantity of powder material is impacted with a power ram at a controlled velocity in a single controlled impact on the powder material at a controlled specific impulse or specific kinetic energy to adiabatically compact the powder material into a workpiece with a relative density of 95% or above without additional processing such as preliminary compaction, pre-compaction sintering, post-compaction sintering, pre-heating of the powder material (warm compaction), lubrication or multiple impacts.