Tribological Behaviors of Si₃N₄-hBN against PEEK with Precorrosion in Seawater

Abstract

In this article, the tribological behaviors of Si₃N₄-hBN composites and polyether ether ketone (PEEK) materials with precorrosion were investigated in seawater and deionized water, respectively. Si₃N₄-hBN composite represented a good seawater corrosion resistance, and a low corrosion rate of 0.0037 g/(m²·h) was obtained for Si₃N₄-hBN composites in seawater. The seawater absorption rate of PEEK material was about 0.726%, and the surface became rougher with precorrosion. Si₃N₄-hBN/PEEK pairs presented friction coefficients of around 0.20, and some reactive products (e.g., SiO₂ and H₃BO₃) formed on the surface. When the hBN content was equal to 10 wt%, more smooth worn surfaces were presented. In addition, the Si₃N₄-10% hBN/PEEK pair presented the lowest and most stable friction behavior. There were few changes in the Si₃N₄-hBN and PEEK materials before and after immersion in deionized water. The friction coefficients of the Si₃N₄-hBN/PEEK pair were all lowered than 0.1 in deionized water. The corresponding wear rates of pins and discs were all below the order of magnitude of 10⁻⁶ mm³/Nm. The excellent tribological characteristics were attributed to ultrasmooth surfaces (originated from the tribochemical reaction).

Keywords:

• Corrosion
• applied tribology
• ceramic composite
• polymers

Additional information

Funding

The authors are thankful for the funding provided by the Natural Science Foundation of Shaanxi Province, China (Grant No. 2018JM5056); National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials (Grant No. HKDNM2019012); Natural Science Foundation of China (Grant No. 51905325); and China Postdoctoral Science Foundation (Grant No. 2019M653525).