Wear resistance process comparisons

In some applications the lack of toughness of ceramics or CMCs prohibits their use. In cases where enhanced stiffness, wear resistance, or elevated temperature capabilities greater than those provided by metals are necessary, metal matrix composites (MMCs) offer a reasonable compromise between ceramics or CMCs and metals. Typically, MMCs have discrete ceramic particulate or fiber reinforcement contained within a metal matrix. In comparison to CMCs, MMCs tend to be more workable and more easily formed, less brittle, and more flaw tolerant. These gains come primarily at the expense of a loss of high-temperature mechanical properties and chemical stability offered by CMCs. These materials thus offer an intermediate set of properties between metals and ceramics, though somewhat closer to metals than ceramics or CMCs. Nonetheless, like ceramic matrix composites, they involve physical mixtures of different materials that are exposed to elevated temperature processes, and therefore evoke similar thermodyamic considerations for reinforcement stability. 

These antifrictional materials of INHAM grade display higher wear resistance under friction in the liquid hostile media compared to non-inhibited plastics. For comparison, the properties of an antifrictional material based on PA6 and molybdenum disulfide without a Cl in its composition are presented in Table 4.13. Its wear resistance is seen to fall short of the INHAM materials since corrosion processes are not suppressed in the friction zone of this material with the metal. 

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