High Strength, Affordable Helicopter Gears

The Army's SBIR Phase I solicitation seeks to demonstrate the potential for improved bending and contact fatigue strength of gear alloys for increasing the power density of main helicopter gearboxes. QuesTek Innovations proposes to utilize advances in gear steel technology and surface treatment processes to address these objectives. It is possible to improve gear performance through both advanced materials and surface treatments. QuesTek will evaluate laser shock peening as an improvement to traditional shot peening to increase bending and contact fatigue strength for test coupons of conventional Pyrowear 53. Additionally, advanced gear steel test coupons of GearMetO C61 and GearMetO C69 will be evaluated as superior alternatives to Pyrowear 53. Material improvement and an optimal surface treatment will allow for an increase in fatigue strength and a subsequent increase in gearbox power density. QuesTek will team with Bell Helicopter to evaluate the potential benefits of incorporating laser peening of Pyrowear 53 and to additionally evaluate GearMet C61 and C69 for both military and commercial helicopter gear systems. Results of Phase I coupon tests will be used to establish the feasibility that Phase II gearbox testing has a significant probability of achieving a 25% improvement in bending and contact fatigue.