The influence of tempering and annealing on the microstructure and sliding wear response of G350 grey cast iron

The present study investigates the tribological properties of G350 grey cast iron in various microstructural conditions. Quench and temper heat treatments were conducted at four tempering temperatures, from 400 degrees C to 700 degrees C, to produce a range of tempered martensitic disc samples. Pins were slow furnace-cool annealed to produce a coarse pearlitic microstructure with some areas of ferrite. These samples were then used in pin-on-disc sliding wear tests. Hardness decreased with tempering temperature, from 400HV at 400 degrees C to 200HV at 700 degrees C. The two spheroidized carbide discs produced higher volume losses than the two acicular martensitic discs due to instability of the oxide layer on the softer substrate. Subsurface deformation was visible in the annealed pins and spheroidized discs which consisted of deformed cementite lamellae in the direction sliding and strained ferrite grains.

Automated summary

This study investigates the tribological properties of G350 grey cast iron in different microstructural conditions. Samples with different microstructures were produced through quench and temper heat treatments at various tempering temperatures. Pin-on-disc sliding wear tests were conducted to evaluate the performance. The results showed that increasing tempering temperature led to a decrease in hardness, and spheroidized carbide discs had higher volume losses compared to acicular martensitic discs. Subsurface deformation was observed in annealed pins and spheroidized discs.