Abstract: In order to investigate the effects of rake angle on rock cutting, a linear rock cutting device was invented and used to conduct rock cutting experiments with chisel picks on sandstone with rake angle ranging from -40° to 50°. The interaction forces between picks and rocks were real-time recorded. The grooves created in the experiments were captured. The pieces of debris were collected and the size distribution was obtained. The fractal features of the debris pieces were analyzed. And the debris pieces’ size distribution was quantitatively described by their fractal dimension. The results show that with the increasing of rake angle from -40° to 50°, the width of the groove increases, especially in the initial part of the groove. The fractal dimension of the debris and the cutting force on the picks decrease gradually with the increasing of the rake angle. They can be expressed by the exponential function of the rake angle. However, the ratio of mean cutting force to mean normal force remains between 0.56 and 1.84, and seems not be affected by the rake angle.

Key words: rocks, cutting, rake angle, cutting force, fractal dimension, size distribution