The wear of slipping wheels

Abstract A wheel is said to slip if its travelling velocity differs in absolute value from the circumferential velocity, or if it has a component in the direction of the axle. Slip produces sliding which is in general confined to the rear part of the area of contact, the sliding range increasing with increasing slip. Assuming proportionality between abrasion and frictional energy dissipation, wear has been calculated for a simple model as function of slip and physical properties of the wheel. At moderate slip, wear is found to increase as the square of the slip; at constant slip, wear increases with increasing stiffness, and decreases with increasing elastic hysteresis of the wheel. The results allow an estimate to be made of the dependence of wear on speed of travel under practical conditions. Experimental evidence is adduced in support of the theory.