Copper in low alloyed grey cast irons

Samples of cast iron SCh 20 with 1.8%Cu were analysed by means of Auger electronic spectroscopy before and after cyclic heat treatment (heating up to 350°C, 15 sec and cooling in air 15 sec). In the initial state copper concentration at grain boundaries reached 4.2%, at a machined surface 0.35% and after 500 cycles of heat treatment 6.3% and 2.8% accordingly. Copper precipitation on the surface of components at friction contributes to the decrease of the friction coefficient and increase in wear resistance.