The effect of surface nanocrystallization on the durability of structural steel

The influence of the surface nanocrystalline structure of the alloy structural steel generated by frictional treatment on the contact durability in oil and tap water was investigated and compared with that for steels treated with cementation, quenching and tempering. It was revealed that the surface nanocrystalline structure formed by the treatment in oil fluid and in aqueous emulsol solution increased contact durability of the steel in approximately 2 times in oil compared to cementation with further quenching and low-tempering; the contact durability of the same specimens in water remained changeless. The treatment in air resulted in the highest contact durability; however, it led to decrease in the surface roughness. The contact durability in the oil is significantly higher compared to that in the tap water.