Forming principles of negative shear in precision machining

摘要

The negative shear is one of the common phenomena occurring in metal cutting. In this paper, forming and changing of the negative shear area during the tool cut out workpiece end have been studied systematically based on the orthogonal metal cutting experiments. A cutting model of the negative shear formation is made, main factors influencing negative shear formation are pointed out, a important physical parameter in forming and changing of negative shear is given critical undeformed chip thickness h{sub}(DI), effect results of many factors on critical undeformed chip thickness h{sub}(DI) have been analyzed and discussed by experiments, and basis laws of the negative shear formation and change is announced systematically. The study may be important science value for developing of metal cutting principles and precision machining theory.