Comparison in abrasion resistance between hardened 8620 steel and coated by Ti/TiN

Abstract

The abrasive wear of 8620 tempered and quenched steel under aggressive conditions was investigated and it is compared with samples of 8620 steel recovered by layers TiN in the same abrasion conditions. Thermal treatment of the 8620 steel specimens was carried out at 900°C until room temperature. After quenching, the samples wear tempered below the martensitic temperature in order to increase hardness and wear resistance. Recovering samples 8620 steel with TiN were made by magnetron sputtering technique. In these experiments, a suspension of silica sand (1.5 dm3) and water (0.94 dm3) was employed as a very aggressive abrasive wear agent. The tribometer used in the abrasion tests, of the wet-sand/rubber-wheel type, was designed and constructed by the second author according to the ASTM G-105 specification. Weight loss of the specimens was measured as a function of the number of cycles and the sliding distance. These results are discussed and compared. Significant improvement in the wear resistance of the recovered steel were observed when compared to the thermal treated samples.