Wear of antifriction cermet materials under conditions of end-face sliding friction

1. Iron-based antifriction cermet materials containing graphite or zinc sulfide can be used for endface packing rings operating at high sliding friction velocities under low pressures, for instance, 50m/sec and 1–1.5 daN/cm2. 2. In order to ensure reliable operation of packings and broaden the scope of application of the above materials, it is necessary to improve their strength and bearing capacity. This can be achieved by using high-dispersity initial powders, increasing the density, eliminating large pores and solid-lubricant impurities by securing a uniform pore and impurity distribution, and orienting extended pores and impurities in the direction perpendicular to the friction surface. 3. Special attention should be paid to the preparation of the friction surfaces, the choice of the processing methods and conditions, and the proper planeness and finish of the working surfaces. 4. Depending on the actual conditions under which the packings operate, it is necessary to determine the optimum percentage of sulfide and graphite additions that perform the function of dry lubricant in order that these percentages do not substantially reduce the mechanical strength of the basic metal.