Tribological Performance of Friction Pairs with Different Materials and Bi-Composite Surface Texture Configurations

Abstract

Bi-composite surface texture configurations are proposed to study the friction performance of a mechanical seal under low speed. Three sets of comparative experiments were designed. They involved friction pairs with different pairing materials, single texture patterns, and bi-composite surface texture configurations. Tribological performances, such as friction coefficient, wear quantity, and surface topography, were measured. The research results showed that the average friction coefficient and surface temperature rise of the 3-C3 group (triangular texture in SSiC–conventional spiral groove in SSiC) were only 0.052 and 3.8 °C, respectively, which was the smallest friction coefficient and lowest temperature rise of all the test subjects. What’s more, the wear of M120D was mainly caused by the cutting effect of the texture edges, the adhesive wear of the non-textured areas, and the secondary wear caused by debris from the internal texture. It was indicated that the bi-composite patterns of spiral-triangle could produce a ‘synergistic effect’ by improving tribological performance and reaching lower friction in low-rotational-speed operation, which could provide a basis for designing a long-lasting and exceptionally reliable mechanical seal.

The Tribological Performance of Frictional Pair of Gas–Liquid Miscible Backflow Pumping Seal in Oil–Air Environment

“…Conversely, the COFs of the four frictional pairs composed of Al2O3 coating, Cr2O3 coating, Metal-IG, and Resin-IG gradually decreased with increasing rotational speed. This trend is consistent with Engqvist and Zhang's study [20,25,41]. The COFs of Al2O3 coating and Metal-IG and Cr2O3 coating and Metal-IG at low speed were lower than that at dry friction [20], indicating that a small amount of lubricant in an oil-air environment can effectively improve the lubrication condition of the frictional pair and obtain a lower COF.…”

“…This trend is consistent with Engqvist and Zhang's study [20,25,41]. The COFs of Al2O3 coating and Metal-IG and Cr2O3 coating and Metal-IG at low speed were lower than that at dry friction [20], indicating that a small amount of lubricant in an oil-air environment can effectively improve the lubrication condition of the frictional pair and obtain a lower COF. Qiu [21] observed a COF phenomenon in oil lubrication, which first decreased and then increased with the rotational speed, and believed that the lubrication condition of the frictional pair changed from mixed lubrication to hydrodynamic lubrication.…”

“…Apart from the physical and chemical properties of the frictional pair materials, the friction conditions have a great influence on their tribological properties. Previous studies on the tribological performance of mechanical seal frictional pairs have mainly focused on dry friction, water lubrication, or oil lubrication [6,[18][19][20][21]. Under dry friction, graphite tends to transfer to the friction surface, reducing the direct contact between the frictional pairs [22][23][24][25][26].…”

Dry Friction Properties of Diamond-Coated Silicon Carbide

“…Mechanical seals, as important key components in rotating equipment to prevent leakage of process media or lubricating oil, ensure safe production, save energy and contain pollution, are widely used in major equipment in petrochemical, coal chemical, marine engineering, aerospace and other industries [ 1 ]. With the development of industry, energy and environmental requirements, the operating conditions of mechanical seal become more and more complex, involving such parameters as ultra-high pressure, ultra-high speed and high temperature [ 2 , 3 ].…”

Wear mechanism and leakage failure analysis of the mechanical seal end face of an oil transfer pump

“…Lu et al 3 studied the effects of fabric orientation, load, and sliding speed on the tribological properties and wear mechanism of composite materials and pointed out that C/C composite materials have good tribological and mechanical properties, and their application in sealing can effectively solve the problem of sealing wear. Lu et al 4 proposed the double composite surface texture configuration to study the friction performance of mechanical seals at low speeds. The results showed that the spiral triangle double composite structure could produce a "synergistic effect" by improving the tribological performance and reducing the friction at low speed, which provided a basis for the design of durable and reliable mechanical seals.…”