Ceramic conversion treatment of zirconium alloys to combat corrosion wear

Abstract

A series of ceramic conversion treatments have been conducted on Zr702 and Zr705 zirconium alloys by thermal oxidation at temperatures ranging from 400 to 700uC for 3-30 h. A wide range of material characterisation techniques were used to investigate the microstructure, composition, phase constituent, load bearing capacity and wear properties of the surface treated zirconium alloys. Experimental results show that after ceramic conversion treatments, the surfaces of Zr702 and Zr705 alloys can be converted to a ceramic layer consisting of a-ZrO 2 and b-ZrO 2 ; the optimal ceramic conversion treatment conditions for Zr702 and Zr705 alloys are 600uC/10 h and 600uC/ 3 h respectively; Zr705 alloy has a better response to ceramic conversion treatment than Zr702; and the wear resistance of the optimally treated zirconium alloys can be improved by more than 200 times. The wear mechanisms of both untreated and ceramic conversion treated zirconium alloys are discussed. The dominant wear mechanisms changed from severe adhesive wear for the untreated zirconium alloys to mild abrasive wear for the ceramic conversion treated materials.

Ceramic conversion treatment of titanium-based materials

“…For example, when the ceramic layer on CP-Ti is doped with Pd, its corrosion resistance in boiling 20% HCl solution can be significantly improved (Table 14.2). Furthermore, CCT technology has recently been applied to zirconium-based alloys to combat wear (Ji et al, 2010). 14.7…”

Coatings tribology drivers for high density plasma technologies

“…The authors express thanks to Cambridge University Press for permission to reproduce Figs 1,3,8,9,10,11,13,14,15,16 that have been taken from the forthcoming book ''An Introduction to Surface Engineering'' by P. A. Dearnley. The assistance and inspiration of Dr T. Liskiewicz, iETSI, School of Mechanical Engineering, University of Leeds, UK in contributing to the creation of Figs 28 and 29 is gratefully acknowledged.…”

Effect of oxidation time on the tribological behavior of thermally oxidized commercially pure zirconium under dry sliding conditions

“…However, with a base hardness of about 200 HV, zirconium and its alloys have poor tribological properties and find limited applications in other fields of engineering [4]. Efforts have been made to improve the wear resistance of zirconium through extending the oxide film on the surface, mainly by thermal oxidation [4][5][6][7] and plasma electrolytic oxidation [8,9]. With a bulk hardness of 1200 to 1300 HV, a sufficiently thick ZrO 2 film can provide zirconium with excellent resistance to abrasion and wear [4][5][6][7][8][9].…”