Adiabatic shear banding and scaling laws in chip formation with application to cutting of Ti–6Al–4V
| Autor: | Alain Molinari, X. Soldani, María Henar Miguélez |
|---|---|
| Přispěvatelé: | Laboratoire d'Etude des Microstructures et de Mécanique des Matériaux (LEM3), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Arts et Métiers Sciences et Technologies, HESAM Université (HESAM)-HESAM Université (HESAM), Universidad Carlos III de Madrid [Madrid] (UC3M) |
| Rok vydání: | 2013 |
| Předmět: |
0209 industrial biotechnology
Materials science Convective effects 02 engineering and technology Adiabatic shear band Numerical and analytical modeling Physics::Fluid Dynamics [SPI]Engineering Sciences [physics] 020901 industrial engineering & automation 0203 mechanical engineering Machining Material failure theory Scaling laws Mechanical Engineering Chip formation [CHIM.MATE]Chemical Sciences/Material chemistry Mechanics Condensed Matter Physics Shear (sheet metal) Metal cutting Serration 020303 mechanical engineering & transports Mechanics of Materials Free surface Adiabatic shear banding Shear band |
| Zdroj: | Journal of the Mechanics and Physics of Solids Journal of the Mechanics and Physics of Solids, Elsevier, 2013, 61 (11), pp.2331-2359. ⟨10.1016/j.jmps.2013.05.006⟩ |
| ISSN: | 0022-5096 |
| DOI: | 10.1016/j.jmps.2013.05.006 |
| Popis: | International audience; The phenomenon of adiabatic shear banding is analyzed theoretically in the context of metal cutting. The mechanisms of material weakening that are accounted for are (i) thermal softening and (ii) material failure related to a critical value of the accumulated plastic strain. Orthogonal cutting is viewed as a unique configuration where adiabatic shear bands can be experimentally produced under well controlled loading conditions by individually tuning the cutting speed, the feed (uncut chip thickness) and the tool geometry. The role of cutting conditions on adiabatic shear banding and chip serration is investigated by combining finite element calculations and analytical modeling. This leads to the characterization and classification of different regimes of shear banding and the determination of scaling laws which involve dimensionless parameters representative of thermal and inertia effects. The analysis gives new insights into the physical aspects of plastic flow instability in chip formation. The originality with respect to classical works on adiabatic shear banding stems from the various facets of cutting conditions that influence shear banding and from the specific role exercised by convective flow on the evolution of shear bands. Shear bands are generated at the tool tip and propagate towards the chip free surface. They grow within the chip formation region while being convected away by chip flow. It is shown that important changes in the mechanism of shear banding take place when the characteristic time of shear band propagation becomes equal to a characteristic convection time. Application to Ti-6Al-4V titanium are considered and theoretical predictions are compared to available experimental data in a wide range of cutting speeds and feeds. The fundamental knowledge developed in this work is thought to be useful not only for the understanding of metal cutting processes but also, by analogy, to similar problems where convective flow is also interfering with adiabatic shear banding as in impact mechanics and perforation processes. In that perspective, cutting speeds higher than those usually encountered in machining operations have been also explored. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect