Mathematical modelling for predicting heat transferred into biomaterial based on generated spindle speed and feed rate

Bone cutting particularly for cortical bone has received significantly attention in orthopedic surgery. The main challenge in bone cutting is the mechanical and thermal damage to the bone tissue caused by high-speed power equipment. Bone thermal injury known as necrosis can cause by elevating temperature around the operation area to higher than 47 °C for one minute. The aim of this study is to develop mathematical model based on Fourier’s law of heat conduction that can combine with generated moving heat source to predict the cutting temperature. Milling experiments were carried out on artificial bone of polyurethane block, using ZrO2 cutting insert with feed rates of 300 and 500 mm/min, spindle speed of 900 and 1000 RPM, and axial depth of cut of 1.3 mm. Real-time temperatures during the milling process were measured by 8 channels K-type thermocouple that was placed equally on both side of the workpiece. As the results, the predicted temperature range from 30 °C to 42 °C. The predicted temperature at the required points resulted in the temperature lower than limit temperature for necrosis to occur. The outcomes from this study of artificial bone cutting using ceramic cutting insert are significant result for orthopaedic applications.