Size effects in micro drilling of carbon fiber reinforced plastic composite

The contribution presents investigations regarding the size effects on cutting forces in micro drilling of carbon fiber reinforced plastic composite. Generally, size effect is described as non-linear increase of specific cutting force with decreasing chip thickness. Specific cutting forces are determined by dividing cutting force components by chip area. In a mathematical model, specific cutting force is expressed as a function of the ratio of undeformed chip thickness to cutting edge radius. The coefficients of the model are determined by regression analysis using experimental results. Non-linear increase of specific cutting force is observed when the ratio decreases, especially when the ratio is less than unity.