FE simulation of cryogenic assisted machining of Ti alloy (Ti6Al4V)

Abstract

Titanium alloys are well-known material because of the excellent mechanical/chemical properties, corrosion resistance and light weight. These alloys are widely used in the high performance applications such as; aerospace, aviation, bioimplants, turbine blades etc. Machining is commonly used to create products out of Ti alloys. Despite of good material properties, Ti alloys have low thermal conductivity, poor machinability, burr formation, high machining temperature, tool wear and poor machinability. The tool wear and high machining temperature can be controlled through coolant. Cryogenic fluid (liquid nitrogen) is a common material used as coolant in various machining process. The current work is focused on the modeling of cryogenic machining on titanium alloy (Ti6Al4V). Dry machining and cryogenic machining processes are modeled for the chip formation and cutting forces in 2D. Experimental works have been performed to validate the model based on the cutting forces and chip morphology. It is showed that the model is capturing the process, evident by the cutting forces and the chip morphology. The error in prediction is limited to 18%. Model showed that the cutting forces are increasing in cryogenic machining due to the increased strength of the workpiece at low temperature. Chip formation is well captured by the current model. Shear band width have been captured in dry machining. Chip curling has been captured at dry and cryogenic machining. It is expected that the model can further useful in the selection of cryogenic process parameter, such as, flow rate, application techniques etc.