Mechanical properties and erosive behaviour of 10TiO₂-Cr₂O₃ coated CA6NM turbine steel under accelerated conditions

Abstract

Purpose

This paper aims to evaluate the mechanical properties and slurry erosion behaviour of 10TiO2-Cr2O3 coated turbine steel.

Design/methodology/approach

Slurry erosion experiments were performed on the coated turbine steel specimens using slurry erosion test rig under accelerated conditions such as rotational speed, average particle size and slurry concentration. Surface roughness tester, Vickers microhardness tester and scanning electron microscope were used to analyse erosion mechanism.

Findings

Under all experimental conditions, 10TiO2-Cr2O3 coated steel showed better slurry erosion resistance in comparison with Al2O3 coated and uncoated steel specimens. Each experimental condition indicated a significant effect on the erosion rate of both coatings and uncoated steel. The surface analysis of uncoated eroded specimen revealed that plastic deformation, ploughing and deep craters formation were the reasons for mass loss, whereas microchipping, ploughing and microcutting were the reasons for mass loss of coated specimens.

Originality/value

The present investigation provides novel insight into the comparative slurry erosion performance of high velocity oxy fuel deposited 10TiO2-Cr2O3 and Cr2O3 coatings under various environmental conditions. To form modified powder, 10 Wt.% TiO2 was added to 90 Wt.% Cr2O3.

Citation

Goyal, K. (2019), "Mechanical properties and erosive behaviour of 10TiO₂-Cr₂O₃ coated CA6NM turbine steel under accelerated conditions", World Journal of Engineering, Vol. 16 No. 1, pp. 64-70. https://doi.org/10.1108/WJE-08-2018-0262