Study of Measuring Temperature of Burnishing Process Using Diamond Tip Tool

―Application of the Tool-workpiece Thermocouple Method―

Abstract

The surface finishing process has been evaluated in terms of its comprehensive performance as well as it has also been evaluated by its productivity and environmental effect. Burnishing is a surface finishing process for metal products after machining. This process utilizes the plastic deformation of the workpiece surface and yields a smooth surface. In addition, residual stress occurs in the processed workpiece surface. Therefore, the fatigue strength and abrasion resistance of the workpiece are improved. However, friction heating is a severe problem in maintaining the workability of a diamond tip burnishing tool. To estimate the temperature rise caused by burnishing, a new burnishing tool made of boron-doped chemical vapor deposition (CVD) diamond was developed. Its temperature and other characteristics were determined by the tool-workpiece thermocouple method. The thermoelectromotive force was measured and calibrated to temperature using the obtained calibration curve. The tool temperature was found to increase with the rotation speed. The tool temperature obtained under experimental conditions using the highest rotation speed was about 950-960 ℃. Moreover, black scratches as seen in tool wear were observed.