US EPA

4844870 

Journal Article 

On the mechanism of tool crater wear during titanium alloy machining 

Hatt, O; Crawforth, P; Jackson, M 

2017 

1 

Wear
ISSN: 0043-1648
EISSN: 1873-2577 

374 

15-20 

10.1016/j.wear.2016.12.036 

WOS:000395954700003 

Tool crater wear is a major cause of accelerated tool failure during the machining of titanium alloy components. This paper presents a static diffusion couple method which replicates the complex reaction mechanisms occurring at the tool-chip interface during machining and is validated with dynamic turning trials. The diffusion couple tests are realised via the use of a bespoke vacuum compression rig. The rig consists of two graphite rods which secure the sample under a clamping load at the required temperature and pressure. Titanium alloys bearing a high molybdenum content are found to be less susceptible to TiC formation at the tool-workpiece interface. A TiC layer during machining coats and protects the tool from excessive crater wear therefore increasing tool life. Strong agreement was found between the diffusion couple technique and turning trial. This low cost test strategy will be used to design machinable titanium alloys and more compatible tools. (C) 2017 Elsevier B.V. All rights reserved. 

Machining; Metal cutting; Titanium alloys; Diffusion; Tool wear mechanisms; EDS analysis