Wear Investigation of Finish Rolled Powder Metal Gears

When manufacturing powder metal (PM) gears lead crowning is not achievable in the compaction process. This has to be accomplished either by shaving, grinding or honing. Each of these processes has their merits and draw backs. When employing rolling using a roll burnishing machine lead crowning can be accomplished but due to errors in profile a hard finishing operation such as grinding is used by the industry. In this paper a helical PM gear that has sufficient tolerance class after rolling has been tested in a test rig for durability and the wear has been studied.