To meet a goal of at least a 25% improvement in helicopter gear tooth bending fatigue life, a project was initiated by DCT under US Army Aviation Technology Directorate sponsorship to improve the compressive residual surface stress state by applying intensive quenching in place of conventional oil quenching. The feasibility was demonstrated and reported upon using a carburized and quench hardened notched bar sample subjected to three point bend testing. This paper reports the results of single tooth bending fatigue tests for carburized and quench hardened Pyrowear 53 steel gears. The fatigue test data show that intensively quenched gears had higher life in comparison to conventionally heat treated gears. The surface residual stress state had a higher magnitude of compression for the intensively quenched gear than for the oil quenched gear. Computer simulations of the heat treat processes provided a sound understanding of why these quenching methods produced different bending fatigue strength for essentially the same martensitic microstructures and hardness levels.
Improving gear performance by intensive quench
Verbesserung der Getriebeleistung durch intensives Abkühlen
2007
7 Seiten, 14 Bilder, 3 Tabellen, 2 Quellen
Conference paper
English
The Influence of the Quenching Characteristics of Quench Oils on Distortion of Automotive Gear Parts
British Library Conference Proceedings | 1999
|Automotive engineering | 1983
|Improving Fatigue Life of Caburized Pyrowear 53 Gears by Enhanced Quench Hardening
British Library Conference Proceedings | 2007
|Design Principles for the Quench Zone of Rich-Quench-Lean Combustors
British Library Conference Proceedings | 1999
|C2Br2F4 Plasma Quench Investigation
AIAA | 1977
|