Tribocorrosion behavior of Ni-17.5Si-29.3Cr alloy in sulfuric acid solution

The tribocorrosion property of a Ni-17.5Si-29.3Cr alloy against a Si3N4 ball was studied in comparison with AISI321 stainless steel using a ball-on-disk reciprocating tribotester in 1 M sulfuric acid (H2SO4) solution. The effects of load and sliding speed on the tribocorrosion properties of the alloy were investigated. The results indicated that the wear rate of the alloy increased while the friction coefficient decreased with increasing load. The wear rate of the alloy increased linearly with increasing sliding speed and the friction coefficient increased in the initial stages and then remained constant with increasing sliding speed. The wear mechanisms were mainly microploughing, uniform corrosion and pitting corrosion. Under the experimental conditions of the present study, the Ni-17.5Si-29.3Cr alloy showed excellent corrosion-resistence and anti-wear ability compared with AISI321 stainless steel.