EFFECT OF TECHNOLOGICAL FACTORS ON THE DEFORMATION OF GEAR WHEELS IN GAS CARBURIZING AND QUENCHING

1. Quenching deformation (warping) or parts does not depend on the regime and method of quenching alone but also on the kinds and methods of the preceding gas carburizing and heat treatment. To reduce the scatter and mean magnitude of quenching deformation and warping of large disk wheels with splined hole, we recommend accelerated air cooling of forgings and of forged blanks, high tempering (at 620-640°C, 4 h) after rough machining, heating for quenching in a protective atmosphere with subsequent cooling in oil at 150-180°C. 2. In view of the stronger effect of the placing of the parts in carburization on the quenching deformation, this factor has to be regarded as decisive in the choice of the method of immersing the part in oil in quenching. 3. The effect of each investigated factor on deformation (warping) in quenching is judged according to several measured traits. The reliability of such an effect depend on the "sensitivity" of the structural elements (toothed rim, spline grooves in the hole, etc.) to the technological effects of heat treatment and carburization. © 1990 Plenum Publishing Corporation.