7 - Effects of surface modification (surface treatment) on friction and surface abrasion of ceramic composites

Abstract

Ceramic matrix composite (CMC) materials are very suitable for tribological applications given their outstanding hardness, high abrasion resistance, good chemical resistance, high temperature stability, etc. Ceramic pairs are often used in extreme environmental applications, such as high loads, high speeds, high temperatures, and corrosive environments. However, their tribological performance is limited by friction and abrasion due to high loss of energy and increase in surface roughness, which in turn degrades the materials. This chapter presents a brief and concise review on the effects of surface modification on friction and abrasion behavior of CMCs. A detailed review of ceramic composites was considered, taking into account the details of the constituents, that is, the matrix phase, the reinforcing phase, and the interfacial domain. Different kinds of CMCs were also considered, highlighting their relative merits. Friction and abrasion of ceramic composite systems were also discussed. Friction of CMCs depends largely on fracture toughness besides normal load, sliding speed, temperature, etc. Abrasion mechanisms in CMCs necessitate fracture, tribochemical effects, and plastic flow. Surface modification was reviewed considering various surface modification techniques on different CMCs and the consequent impact on friction and abrasion. In conclusion, it is absolutely clear that CMCs are highly attractive materials with a high percentage of modern applications especially in tribo systems. However, optimum performance is limited by high friction coefficients and high abrasion rates; nevertheless, surface modification with the appropriate matrices and/or reinforcements materials has been found a wonderful solution.