A study of chip formation in ductile-regime machining of 6H silicon carbide by molecular dynamics. (2015)

• Record Type: Journal Article
• Authors: Xiao, Gaobo; To, Suet; Zhang, Guoqing
• Is Part Of: International journal of nanomanufacturing. Volume 11:Number 1/2(2015)
• Page Start: 64
• Page End: 77
• Publication Date: 2015
• Subjects: silicon carbide -- SiC -- ductile regime machining -- molecular dynamics -- chip formation -- nanomanufacturing -- simulation -- nanotechnology -- shearing -- extrusion -- tool rake angle -- plastic deformation -- cutting force; Nanostructured materials industry -- Periodicals; Nanotechnology -- Periodicals; 620.505
• Languages: English
• ISSNs: 1746-9392

Abstract

Much effort have been devoted to the ductile regime machining of silicon carbide (SiC) in recent years. However, a thorough understanding on the mechanism of chip formation has not been achieved. In this study, large scale molecular dynamics simulations are performed to investigate the ductile-regime machining of 6H SiC. It is found that the mechanism of chip formation transforms from shearing to extrusion when the tool rake angle varies from 0° to −40°. The nature of plastic deformation is slipping processes on the basal slip system of 6H SiC and shearing along several inclined planes. Under a rake angle of −40°, a 'pseudo edge' is observed in front of the cutting edge throughout the cutting process. Under a rake angle of −20', a periodic process of formation and vanishing of 'pseudo edge' is observed. The formation of 'pseudo edge' leads to a decrease in the principle cutting force, and its vanishing is followed by increase of principle cutting force.