Semiempirical heat flux model of hard-brittle bone material in ductile microgrinding

Biological compact bone tissue is a typical hard-brittle material, which is extremely sensitive to high temperature. For the calculation of bone microgrinding temperature field, most of the known methods are based on the constant heat flux of the average tangential force without considering the ductile grinding characteristics of bone, leading to large calculation error. A semiempirical heat flux theoretical model based on the dynamic grinding force of hard-brittle bone ductile microgrinding is proposed to solve this bottleneck problem. The mechanism of heat generation and consumption in microgrinding zone under ductile removal mode of bone material is studied first, and the probability statistics of effective cutting abrasive number is analyzed. The heat distribution coefficient in grinding zone is calculated, and the semiempirical heat flux model of the ductile removal of hard-brittle biobone material is developed. Microgrinding experiments are conducted to verify the effectiveness of ductile removal grinding heat flux model. The temperatures of different measuring points on the surface of bone samples and micro grinding force are measured. Results show that the theoretical calculation is consistent with the experimental results, with an average error of <7.7%. Mechanical processing theory is applied to medical rehabilitation for realizing the precise control of temperature field in hard-brittle bone microgrinding process.