Abstract:

In order to figure out the burnout problem during grinding process, a novel method about enhancing heat transferring in the contact zone by incorporating a revolving heat pipe inside the wheel disk has been proposed. By designing the structure and analyzing the heat transfer process of heat pipe grinding wheel (HPGW), factors as working fluid kind, fluid loading and rotating speed are determined to be the main factors that may affect its heat transfer capacity. Heat transfer analysis experiments were complemented on a self-designed experiment platform, on which the influences of different factors are investigated. According to the results of the heat transfer analysis experiments, a CBN HPGW injected with 18 g distilled water is fabricated and applied in creep feed grinding of Inconel 718. The results are compared with non-HPGW in terms of the average temperature in the contact zone, workpiece surface quality, microstructure and micro-hardness of the ground workpiece surface and the grinding wheel surface. Results show that the temperature in the contact zone can be controlled below 60 ℃ when using HPGW, while sever burnout happened when using non-HPGW at the same conditions, which confirmed the excellent heat transfer performance of HPGW.

Key words: creep feed grinding, heat transfer performance, supper alloy, heat pipe grinding wheel