Pressure-Induced Critical Influences on Workpiece-Tool Thermal Interaction in High Speed Dry Machining of Titanium

TL;DR

This study investigates how thermal loads, influenced by thermodynamic forces, affect the failure of coated carbide tools during high-speed dry machining of titanium, emphasizing the complex nonlinear thermal conduction mechanisms involved.

Contribution

It introduces a mechanistic approach considering thermodynamic forces to understand thermal conduction and tool wear in high-speed dry machining of titanium.

Findings

Thermal conduction is influenced by stress, strain, and temperature gradients.

Thermo-physical properties significantly affect tool deterioration.

Non-linear thermal conduction models provide better understanding of tool wear mechanisms.

Abstract

Cutting tools are subject to extreme thermal and mechanical loads during operation. The state of loading is intensified in dry cutting environment especially when cutting the so called hard-to-cut-materials. Although, the effect of mechanical loads on tool failure have been extensively studied, detailed studies on the effect of thermal loads on the deterioration of the cutting tool are rather scarce. In this paper we study failure of coated carbide tools due to thermal loading. The study emphasizes the role assumed by the thermo-physical properties of the tool material in enhancing or preventing mass attrition of the cutting elements within the tool. It is shown that within a comprehensive view of the nature of conduction in the tool zone, thermal conduction is not solely affected by temperature. Rather it is a function of the so called thermodynamic forces. These are the stress, the strain, strain rate, rate of temperature rise, and the temperature gradient. Although that within such consideration description of thermal conduction is non-linear, it is beneficial to employ such a form because it facilitates a full mechanistic understanding of thermal activation of tool wear.