Tribochemical behavior of phosphate compounds at an elevated temperature

Authors

Shaogang Cui, University of WollongongFollow
Shanhong Wan, University of WollongongFollow
Qiang Zhu, University of WollongongFollow
Anh Kiet Tieu, University of WollongongFollow
Hongtao Zhu, University of WollongongFollow
Liping Wang, Chinese Academy of SciencesFollow
Bruce Cowie, Australian Synchrotron

RIS ID

111097

Publication Details

Cui, S., Wan, S., Zhu, Q., Tieu, A. Kiet., Zhu, H., Wang, L. & Cowie, B. (2016). Tribochemical behavior of phosphate compounds at an elevated temperature. The Journal of Physical Chemistry C: Energy Conversion and Storage, Optical and Electronic Devices, Interfaces, Nanomaterials, and Hard Matter, 120 (45), 25742-25751.

Abstract

The tribological behaviors of three types of sodium phosphates (sodium ortho-, pyro-, and metaphosphate) with different chain lengths are evaluated using the ball-on-disk tribometer at 800 °C. The tribological results show that all three sodium phosphates can reduce friction by approximately 45−65% and wear rate by 80−90%, and, among these, shorter-chainlength phosphate shows a lower friction and wear. XPS spectra indicate a phosphate glassy film consisting of Na, Fe, P, and O elements formed on the tribostressed area. The tribochemistry of tribosurface investigated by XPS and XANES reveals that NaPO3 and Na4P2O7 react with oxide wear debris to produce mixed short-chain Na/Fe polyphosphate in the tribostressed area, leading to a severe depolymerization for NaPO3 and a slight polymerization for Na4P2O7. However, little polymerization/ depolymerization was found for crystalline sodium orthophosphate.

Grant Number

ARC/DP150103718