Material removal mechanism beyond plastic wave propagation rate

Discussed in this report are the material removal mechanisms below and beyond its static plastic wave propagation rate. The ductile materials are expected to behave elastically throughout most of its strength range, and apparently become brittle as cutting speed exceeds its static propagation rate. This behavior leads to a significant reduction in plastic flow/deformation and work hardening during the machining process, so as possibly to improve the total surface integrity. In order to achieve such high speed machining, a super high speed grinding machine has been newly developed by using the latest technologies, which is able to attain 600 m/s peripheral speed and 10 nm/step positioning accuracy. This study particularly investigates the cutting speed effect on the typical ductile metals of pure aluminum (A 1199) and aluminum alloy (A5056), and reveals that static propagation rate is a breaking point from where the removal mechanism is different. (C) 2002 Elsevier Science Inc. All rights reserved.