J. Phys. IV France 11 (2001) Pr4-213-Pr4-220
Microstructural modifications and material response in machining of steelsB. Changeux1 and J.-L. Lebrun2
1 LM3, ENSAM-Paris, 151 boulevard de l'Hôpital, 75013 Paris, France
2 LPMI, ENSAM-Angers, 2 boulevard du Ronceray, 49035 Angers cedex, France
In machining with a cutting tool (turning, milling, drilling,...), the loading conditions for the cut material in the cutting zone are extremely severe, in terms of strain (some hundred %), strain rates (~105s-1), temperatures (some hundred °C) and temperature rates (~106 K.s-1). The subsequent microstructural changes are analysed and the problem of the evaluation of the behaviour of the cut material (i.e. of the chip and the workpiece) is discussed, in the view of building a predictive cutting model. X-ray diffraction, microscopy, as well as analytical modelling are used to investigate the small zone under solicitation ahead of the tool tip. Texture, hardness, phase transformation data inside the cutting products attest a very strong heterogeneity in the thermo-mechanical loading from places of the cutting zone to others, which makes cutting a problem difficult to treat under a unique behaviour view.
© EDP Sciences 2001