Method of joining non-fusible workpieces using frictional energy

A method of joining a non-fusible workpiece to a polymeric plastic workpiece comprising:

• providing a planar surface of the non-fusible workpiece with a recess extending from said surface into the interior of said respective workpiece and said recess being shaped for trapping material;
• disposing the other workpiece for contact along a planar surface with said surface of said non-fusible workpiece;
• applying a static force between said workpieces to urge them into intimate contact with one another along the contacting planar surfaces;
• subjecting said workpieces to relative linear reciprocating motion with respect to one another in the plane of the contacting surfaces for causing resulting from frictional energy softening of the material comprising said other workpiece and effecting flowing of such softened material from said other workpiece into the recess of said non-fusible workpiece, and
• stopping said relative motion for causing said softened material to solidify whereby said workpieces become joined on account of the trapped solidified material.