Scuffing Resistance of Advanced Gear Material/Lubricant Combinations

Two advanced carburizing grade gear steels were evaluated and compared against an AMS 6260 baseline material. Each material was evaluated on three lubricants (an unformulated ester basestock, a qualified MIL-L-23699B lubricant, and an advanced MIL-L-23699 type lubricant) to determine their gear scuffing/scoring capacities. The results show that (a) a 3Ni-4.5Mo alloy is superior to a 3Ni-2Cu alloy and to the AMS 6260 alloy with the lubricants evaluated, (b) the 3Ni-2Cu alloy is superior to the AMS 6260 with the fully formulated lubricants, and (c) the advanced MIL-L-23699 type lubricant showed significant load carrying capacity improvements for all three gear steels.