Abstract: Due to the high hardness and wear resistance of difficult-to-machine materials， the grinding wheel wears faster in the grinding process. At present， the dressing and replacement cycle of the grinding wheel is mainly judged by experience， which may lead to untimely dressing. Accordingly， the wear state of grinding wheel was accurately monitored by combining acoustic emission signals and grinding force signals. By analyzing the characteristic parameters of acoustic emission signals， the changes of grinding force and grinding force ratio during the grinding of grinding wheels with different wear states， the wear state of grinding wheels during the experimental process was comprehensively judged. The results showed that the acoustic emission signals are all correlated with the grinding wheels’ wear state， and the grinding force ratio is the most correlated with the grinding wheels’ wear degree， which proves the effectiveness of the acoustic emission monitoring technology in grinding wheel dressing and provides theoretical guidance for the actual production process.

Key words: difficult-to-machine material; grinding process; acoustic emission(AE); grinding wheel wear; monitoring