Tribological properties of 304 stainless steel with rainwater corrosion

Aiming at exploring the influence of rainwater corrosion on the tribological properties of 304 stainless steel, the test samples were immersed in rainwater for corrosion with 6 h, 12 h, and 18 h respectively. The morphology, element content, and wettability of them before and after rainwater corrosion were obtained by white light interferometer, scanning electron microscope, energy spectrum, and contact angle measuring instrument. Then, the hardness and tribological properties were measured by Vickers hardness tester and MWF-500 reciprocating friction and wear tester. The experimental results show that the rainwater has an obviously corrosive effect on the 304 stainless steel surfaces. With the conducting of the corrosive process, the contents of N and S elements are increased which increase the hardness value, surface roughness, and wettability of test sample surface. In this case, the interfacial tribological properties is changed. Small friction coefficient is obtained, and the quantity and depth of surface scratch is decreased in dry friction. For lubricated case, the interfacial tribological properties is improved by rainwater, and small friction coefficient is obtained for corrosive samples. But, the quantity of scratch crack is increased due to the increasing of wear particles. The dissolution of metal impurities on the sample surface leads to the deterioration of the surface morphology, and the diffusion of N and S elements on the sample surface leads to the hardening and embrittlement of the sample surface, The main contribution of this work is in providing a reference for the 304 stainless steel corrosion protection.

Automated summary

This study investigates the influence of rainwater corrosion on the tribological properties of 304 stainless steel. The results show that rainwater has a corrosive effect on the surface of 304 stainless steel, increasing the content of N and S elements, as well as the hardness, surface roughness, and wettability. The interfacial tribological properties are also affected, with a small friction coefficient and decreased surface scratch in dry friction, and improved interfacial tribological properties with a small friction coefficient in lubricated conditions.