Papers by Author: Xun Li

Abstract: Cutting mechanism and characteristics of difficult-to-cut materials have a great difference. Currently, systems or indicators of the machinability are so many that we do not know how to utilize them. Not only because there is no consideration the impact of cutting conditions and parameters on machinability, but they are not be accurate quantitative responses to the machinability of workpiece materials, especially to the difficult-to-cut materials. Based on in-depth analysis of cutting mechanism and objective functions of cutting parameters optimization, an innovative machinability evaluation system based on the variable processing cost per unit material is developed. And the economics of machining process are introduced to the machinability evaluation system. Several classic analysises and calculation examples of the machinability of several typical difficult-to-cut materials have been presented at the end of paper to give a clear picture from the application of the system. The result demonstrates that the machinability evaluation system based on the variable processing cost per unit material has good practicability and maneuverability.

Abstract: The study focused on surface burn of titanium alloy (TC4) in the grinding process using a novel segmented cup wheel with internal cooling structure. The threshold burn temperature was found in grinding TC4. Plastically deformed coating layers and micro-cracks were observed on ground surface by SEM (Scanning Electronic Microscopy) and depth of microstructure alterations was more than 180 microns in high temperature. Finally, a novel wheel with internal cooling structure was developed for reducing grinding temperature and suppressing surface burn.