Abstract:
Tribological properties of Fe-Si-Cr-Al alloys (Fe
65Si
25Cr
5Al
5, Fe
70Si
20Cr
5Al
5, Fe
75Si
15Cr
5Al
5 and Fe
80Si
10Cr
5Al
5) in sliding against a Si
3N
4 ball under water lubrication were evaluated by using an Optimal SRV tribo-meter. The results indicate that the wear rates of Fe
65Si
25Cr
5Al
5 and Fe
70Si
20Cr
5Al
5 were lower than those of Fe
3Si and AISI 304 stainless steel. The wear rate of Si
3N
4 sliding against Fe
65Si
25Cr
5Al
5 and Fe
70Si
20Cr
5Al
5 were low. The wear rate of Fe
75Si
15Cr
5Al
5 and Fe
80Si
10Cr
5Al
5, on the other hand, were relatively higher than those of Fe
3Si and AISI 304 stainless steel. The chemical activity of Cr in Fe
70Si
20Cr
5Al
5 was higher than that of Al in Fe
70Si
20Cr
5Al
5. The enrichment of Cr
2O
3 on the worn surface of Fe
70Si
20Cr
5Al
5 hindered the tribochemical reaction between Si
3N
4 and water, which in turn accounted for the good tribological properties of Fe
70Si
20Cr
5Al
5. Compared with Fe
3Si, the wear rates of Fe
70Si
20Cr
5Al
5 at the loads of 30 N, 50 N, 70 N and 90 N decreased by 15.5%, 20.2%, 31.8% and 38.2%, respectively. Meanwhile, the wear rates of Si
3N
4 against Fe
70Si
20Cr
5Al
5 at the loads of 30 N, 50 N, 70 N and 90 N decreased by 67.9%, 36.9%, 46.6% and 50.6% respectively compared with those of Si
3N
4 against Fe
3Si.