Material Cost Savings in Powder Metal Transfer Case Sprockets and Sun Gears

For years powder metal (P/M) nickel steel sprockets have been in use in the SUV Transfer Case market. The heat-treated, nickel steel powder metal provides a high strength and high wear resistant material for this very demanding application. Recently the cost of nickel has increased from $5 / lb Oct'05 to $24 / lb May'07. Because of this almost 5 fold increase in the commodity price a replacement material for the powder metal nickel steel was sought that would have comparable properties, comparable processing steps at a raw material cost that would be equal to the nickel steel powder metal prices of 2005. A replacement material was found that has comparable properties at a competitive price. Material composition, testing data and microscopic analysis will be presented.