INVESTIGATION INTO NITRIDED SPUR GEARS

The cold forging method has been widely used in industry to produce ma chine parts. In general, gears are produced by shaping or hobbing. One of the shaping techniques is precision forging, which has several adv antages over hobbing, In the present study, cold forging of spur gears from Ti-6Al-4V material is introduced. To improve the surface propert ies of the resulting gears, plasma nitriding was carried out. Nuclear reaction analysis was carried out to obtain the nitrogen concentration , while the micro-PIXE technique was used to determine the elemental d istribution in the matrix after forging and nitriding processes. Scann ing electron microscopy and x-ray powder diffraction were used to inve stigate the metallurgical changes and formation of nitride components in the surface region. Microhardness and friction tests were carried o ut to measure the hardness depth profile and friction coefficient at t he surface. Finally, scoring failure tests were conducted to determine the rotational speed at which the gears failed, Three distinct region s were obtained in the nitride region, and at the initial stages of th e scoring tests, failure in surface roughness was observed in the vici nity of the tip of the gear tooth, This occurred at a particular rotat ional speed and work input.