Coefficient of dry friction

Abstract

This review covers the methodology for determining the coefficient of dry friction compact metal powder of metal on metal surface and the powder of the powder, and the factors of affecting its value. The coefficient of static friction for some compact metal in 2 or more times the coefficient of sliding friction. Among the factors influencing the friction considered tribounit pressure and temperature. Compared to the temperature, the pressure has a greater impact. For metals, the friction can be described by the binomial law, in which the adhesive component, which depends on the pressure, can be many times (up to 100) are superior to the strain component. For a compact gold dry friction coefficient varies from 0,6 to 2,5. For a pair of powder — a compact surface friction coefficient varied: Iron—Steel—from 0,236 to 0,272, copper—steel — from 0,241 to 0,444, steel—steel—from 0,334 to 0,400. For a pair of powder—powder friction changed: iron—iron —from 0,527 to 0,700, copper—copper —from 0,544 to 0,681, steel—steel —from 0,338 to 0,459. Besides the friction coefficient depends on the structure and state of the metal.