Experimental and numerical investigations of the heating influence on the Ti5553 titanium alloy machinability

Abstract

The use of titanium alloys has become more widespread in recent years. Regardless, although research work is enhancing, productivity levels remain low. Several alternatives have been considered and one of the techniques is envisaged is heating assistance. The objective is then to increase the temperature locally in order to benefit from thermal softening. However, the research is based on power-controlled laser assistance where the temperature levels are not considered. For this purpose, this article suggests a study based on a new experimental device which allows to control the temperature of the machined part. After presenting the device and the material used (Ti5553), the study first shows the effect of temperature on cutting forces. Three temperature ranges and three trends are shown. A first where temperature has no effect, a second when there is a substantial gain and a third where temperature has a real impact. In order to understand the existing links, two methods were used. A finite element model integrating a new law of behaviour was developed and shows the very high temperature levels reached in the cutting areas. Then, to better understand the phenomena governing cutting, we looked at chip formation and the link between chip formation, temperature and its effect on the microstructure. After all, an economic analysis completes this article and highlights the small gains of this assistance.