Ductile fracture mechanics and chip separation in cutting. (22nd October 2007)

• Record Type: Journal Article
• Authors: Rosa, Pedro A.R.; Martins, Paulo A.F.; Atkins, A.G.
• Is Part Of: International journal of machining and machinability of materials. Volume 2:Number 3/4(2007)
• Page Start: 335
• Page End: 346
• Publication Date: 2007-10-22
• Subjects: metal cutting -- finite element method -- FEM -- ductile fracture -- fracture toughness -- specific work -- chip separation -- fracture mechanics -- flow stress -- friction -- surface formation -- simulation; Machining -- Periodicals; Metals -- Machinability -- Periodicals; 671.35
• Languages: English
• ISSNs: 1748-5711

Abstract

The role of surface work in modelling metalworking processes in which separation takes place (machining, blanking, etc.) is discussed. Traditional algebraic and finite element analyses of such processes, incorporating only plastic flow and friction, are able to predict quite well the experimentally-observed material flow fields. However they always underestimate the experimental forces when independently-determined mechanical properties (flow stress, toughness and friction at the correct rates and temperatures) are employed. The deficiency in predicting the forces is directly connected to omitting work of surface formation in the analyses. A new experimental test piece is described for the independent determination of the specific work of separation. Values so obtained serve both as a check on the reasonableness of ductile fracture toughness determined from cutting tests and also for calibration of Finite Element Method (FEM) simulations of such processes.