LASER HARDENING OF CRANKSHAFTS MADE OF HIGH STRENGTH CAST IRON.

Optical and electron microscopy, x-ray diffraction analysis, microhardness measurements and wear resistance tests were used to examine the changes in the structure and properties of high-strength cast iron after the effect of the beam of a 2-4 kW CO//2 gas laser travelling at a speed of 1. 25-5 cm/sec. Formation of two types of layers with the zone of melting and the zone of quenching was observed. The heterogeneity of the structures in the zone of quenching causes differences in the microhardness in a relatively wide range. The highest wear resistance at a low degree of wear of the counterbody was recorded in the irradiated specimen in which the zone of quenching extended to the surface.