APPARATUS FOR DIRECTING PLASMA FLOW TO COAT INTERNAL PASSAGEWAYS

摘要

An apparatus (10) for coating surfaces of a workpiece (40, 120 and 142) is configured to establish a pressure gradient within internal passageways (44, 46 and 48) through the workpiece, so that the coating within the internal passageways exhibits intended characteristics, such as those relating to smoothness or hardness. The coating apparatus may include any or all of a number of cooperative systems, including a plasma generation system (12), a manipulable workpiece support system (34, 90 and 122), an ionization excitation system (66 and 116) configured to increase ionization within or around the workpiece, a biasing system (52) for applying a selected voltage pattern to the workpiece, and a two-chamber system (96 and 98) that enables the plasma generation to take place at a first selected pressure and the deposition to occur at a second selected pressure.