Impact of Isotropic Superfinishing on Contact and Bending Fatigue of Carburized Steel

An Isotropic Superfinish (ISF) is produced by a patented chemically accelerated vibratory finishing process using non-abrasive media that is capable of surface finishing hundreds of parts per hour. Rolling/Sliding Contact Fatigue testing shows that this commercial technology virtually eliminates contact fatigue (pitting) in gear test specimens. Bending fatigue is also improved. Gears finished by this method will operate at higher power densities for much longer life cycles when compared to traditionally finished gears. Studies have confirmed that this process is metallurgically safe for both through hardened and carburized alloy steels. ISF can achieve an R_a < 0.038 μm (1.5 μin.) while maintaining an AGMA Q13 gear dimensions. Rolling/Sliding Contact Fatigue, single tooth bending fatigue, and rotating bending fatigue test results are presented.