Table of Contents
ISRN Materials Science
Volume 2011, Article ID 273706, 10 pages
http://dx.doi.org/10.5402/2011/273706
Research Article

Studies on Influence of WC on Scratch and Hot Corrosion Resistance of AISI H13 Steel by Flame-Sprayed Coatings of EWAC 1001

School of Mechanical and Building Sciences, VIT University, Vellore 632 014, India

Received 9 August 2011; Accepted 5 September 2011

Academic Editors: N. Bahlawane and C. Ribeiro

Copyright © 2011 K. Gokul Kumar and N. Arivazhagan. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

This paper presents the experimental investigations carried out to study the influence of addition of Tungsten Carbide (WC) on the scratch resistance and high-temperature corrosion behaviour of flame-sprayed EWAC 1001 coatings on the AISI H13 steel substrate. The improvement in properties was analysed by conducting various tests such as microstructural analysis, microhardness, and scratch tests. Moreover, high-temperature corrosion tests were carried out on the coated as well as uncoated AISI H13 steel by exposing the material to air oxidation at 700°C under cyclic conditions. The thermogravimetric technique was used to establish kinetics of corrosion, whereas XRD and SEM/EDAX techniques which were used to analyze the AISI H13 steel with EWAC 1001 coating containing WC showed better resistance to high-temperature corrosion as compared to that of uncoated AISI H13 steel. It is observed that the formation of Cr2O3, NiO, and NiCr2O4 contributes to the enhancement of high temperature corrosion resistance of the coating. The formation of unprotective Fe2O3 oxide leads to intense spalling and peeling of the scales in the uncoated material. The results presented in this paper would be beneficial for improving properties of tools used in the die-casting industry.