Diamond dressing of vitrified grinding wheels

The aim of the work is to provide a detailed description of grinding and dressing, focusing on definitions, involved phenomena during the operations, different kind of machines and main variables to know for complete understating of the processes. A state of the art on previous tests carried out by Malkin, Murray and Salmon on effects of rotary dressing on grinding wheels performances is presented as well as a definition of Aggressiveness number in finishing processes and studies on utility of acoustic emission signal monitoring during dressing, by Badjer et al. By carrying on the mentioned experiments and expanding the studies to new evaluations, the purpose is to analyse effects of plunge-roll diamond dressing on vitrified grinding wheels performances, establish dressing Aggressiveness number importance in industry for monitoring thermal damage and speeding-up the process (clear correlations between dressing and grinding variables and dressing Aggressiveness number have been noticed), prove the possibility of wheel sharpness assessment and the acoustic emission signal monitoring relevance in dressing. In order to analyse the effects of the plunge roll dressing on grinding wheel performances, tests on a BLOHM grinding and dressing machine, by using a diamond plunge-roll dresser from Meister Abrasives, an Aluminum oxide grinding wheel and several flat steel workpieces have been performed. First of all, the tests will be run with fixed grinding conditions, and finally with variable grinding conditions as well to see the combined effects of grinding and dressing parameters on heat generation. Furthermore, scanning electron microscope has been used for assessing the wheel topography after dressing and differences between dull and sharp dressing have been found out. Additional studies on the topic are necessary as explained in the conclusions, since further developments on grinding and fine-finishing processes are required for modern and future applications in the industry (Krajnik et al.).