The study of surface roughness after thermal-chemical treatment and subsequent grinding

Abstract

The paper deals with the issues connected to the final machining of diffusion layers formed on the 3Kh2V8F die steel surface by boroaluminizing method. It was established that the surface roughness after boroaluminizing increases by 2.6-5.8 times depending on the time-temperature parameters. Therein the temperature affects the surface roughness ascent more significantly than process duration. After boroaluminizing at 950 °C, Ra has increased from initial 1.5 μm to 4 μm and to 5.44 μm after 2 and 4 hours process duration respectively. As for the 1050°C-process, the values increased to 7.7 μm and 8.76 μm after 2 and 4 hours. Fine grinding as a final machining operation (FMO) of diffusion layers reduces surface roughness by 5.8-45 times depending on the boroaluminizing parameters. However, it was established that Ra values after FMO depend on the initial surface roughness after boroaluminizing. The higher the initial roughness, the higher the roughness after fine grinding. This dependence allows proposing technological heredity effect for the investigated study.