Ultrasonic compacting and bonding particles

A method of substantially concurrently compacting and bonding a plurality of solid particles together into a unified mass having a desired shape and particle content greater than about 70% by volume and the balance substantially binder comprising the steps of:

• placing a loose mixture of said particles and a thermobonding agent in a die having said desired shape, said thermobonding agent being selected from the group consisting of thermoplastic and thermosetting materials activateable by heat to bond said particles together;
• positioning a punch in said die contiguous said mixture, said punch conforming substantially to said shape;
• applying compaction pressure to said mixture with said punch to compact said mixture into said die;
• and
• applying sufficient ultrasonic energy to said mixture while applying said pressure to densify said particles, generate sufficient heat in said mixture to activate said thermobonding agent and effect said bonding.