The mechanics of rock cutting

The failure process in rock cutting is observed and the formation of a recompacted crushed zone which sticks to the rake face of the cutting tool and acts as ‘the built-up edge’ in metal cutting is described. Based on observation of the process of rock cutting and some simplifying assumptions a theory is developed on the mechanics of rock cutting. A formula for cutting force is proposed, which is similar to Merchant's well-known formula in metal cutting. Some experimental work was designed to cut plates of specimen rock, by an orthogonal cutting tool. The test results are compared with theory, and the parameters in the formula determined.