TRIBOLOGICAL ANALYSIS OF INFLUENCE OF COOLANT CONCENTRATION DURING GRINDING A MOULD STEEL GRADE

摘要

The removal mechanism during an abrasive process mainly depends on the physical properties and the tribological interactions between the workpiece and abrasive wheel. In hard-brittle materials the interaction with the abrasive grains results in crack formation where the volume of a chip removed can be several times higher than the volume of the trace. Also the specific energy plays an important hole, especially in grinding process that requires high energy per unit volume of material removed. All of this energy is dissipated as heat at the grinding zone (where the wheel interacts with the workpiece). This leads to the generate of high temperatures which can cause various types of thermal damage to the workpiece, such as burning, metallurgical phase transformations, softening of the surface layer, as well as unfavorable residual tensile stresses, cracks and case reduction of fatigue strength. In order to avoid those thermal damages, the correct selection off all grinding parameters, especially the cutting fluid (grinding fluid), is crucial.