Metallurgical-based prediction of stress-temperature induced rapid heating and cooling phase transformations for high speed machining Ti-6Al-4V alloy

Publication date: 5 April 2017
Source:Materials & Design, Volume 119
Author(s): Qingqing Wang, Zhanqiang Liu, Dong Yang, Aziz Ul Hassan Mohsan
Local phase transformations of materials during mechanical machining influence the variation of surface integrity directly. The aim of this work is to investigate the relationship between cutting parameters and phase transformations during high speed machining (HSM) of Ti-6Al-4V. Rapid heating and cooling phase transformation models are firstly proposed based on phase transformation dynamics. Then, the proposed models are implemented into the Ti-6Al-4V cutting simulation model as a user subroutine of Abaqus/Explicit. The simulated results indicate that, in the chip formation process, β phase volume fraction increases from 8% to 90% in the serrated chips and the machined surface at the cutting speed range of 50–600m/min. In the rapid cooling process, the ratio of the transformed α" phase is about 4%. Finally, comparisons of the simulated results and high speed cutting experiments indicate that the developed models can precisely predict the phase transformations during HSM Ti-6Al-4V. The results help to get deeper insights into understanding the phase transformation mechanisms during HSM o Ti-6Al-4V. The research can also provide an instruction for optimizing the cutting parameters to control the surface integrity in machining of Ti-6Al-4V.

Graphical abstract

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