The Study on the Thermal Characteristic and Cutting Force of Laser-Assisted Machining for Sapphire (Al2O3) Material

The Laser-assisted machining technique mainly utilizes high laser power to heat local area before material was removed. It can raise the surface temperature of workpiece immediately and soften the material with input laser heat. Then material is transformed from brittle into ductile and it's suitable for cutting. It efficiently reduces the cutting force and the tool wear, and relatively promotes the tool life and material removal rate, even the surface precision. The other advantage is the small range of laser spot, and it reduces thermal affection to workpiece and reduces thermal stress caused by laser power to minimum degree. In order to control the surface temperature of workpiece by laser more accurately, and maintain material within the elastic-plastic deformation region, the heat transfer model of pulsed laser heating was developed to simulate the temperature distribution of the material in the process of laser assisted machining. Results are of good agreement with experimental data and heat transfer equation is confirmed to simulate truly the heat distribution of laser-assisted machining system.