Surface integrity of finished turned Ti-6Al-4V alloy with PCD tools using conventional and high pressure coolant supplies


Ezugwu E. O. , Bonney J., Da Silva R. B. , Cakir O.

INTERNATIONAL JOURNAL OF MACHINE TOOLS & MANUFACTURE, vol.47, no.6, pp.884-891, 2007 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 47 Issue: 6
  • Publication Date: 2007
  • Doi Number: 10.1016/j.ijmachtools.2006.08.005
  • Title of Journal : INTERNATIONAL JOURNAL OF MACHINE TOOLS & MANUFACTURE
  • Page Numbers: pp.884-891

Abstract

Surfaces generated when machining Ti-6Al-4V alloy with PCD tools using conventional and high pressure coolant supplies was investigated. Longer tool life was recorded when machining Ti-6Al-4V with high-pressure coolant supplies and the recorded surface roughness R-a values were well below the tool rejection criterion (1.6 mu m) for all cutting conditions investigated. The micro-structure of the machined surfaces were examined on a scanning electron microscope. Micrographs of the machined surfaces show that micro-pits and re-deposited work material were the main damages to the surfaces. Micro-hardness analysis showed hardening of the top machined surfaces when machining with conventional coolant while softening of the subsurface layer was observed when machining under high-pressure coolant supplies. The later is probably due to lower heat generated, with the consequent tempering action when machining with PCD tools with high-pressure coolant supplies. The microstructure below the machined surfaces had minimal or no plastic deformation when machining with conventional and high-pressure coolant supplies. (C) 2006 Elsevier Ltd. All rights reserved.