TRIBOLOGICAL INVESTIGATION OF TUNGSTEN CARBIDE AND HARD CHROME COATINGS ON EN19 FOR COLD ROLLING APPLICATION

In the heavy sheet metal industry, rolls are generally made up of EN19. To enhance the life of the cold rolling mills it can be coated. This paper presents an experimental study to check the effect of alloy coatings such as Hard Chrome and Tungsten carbide on wear resistance and other characteristics of roller base materials EN19 which is used in rolling process of heavy metal industry. In this paper a comparative tribological study of Hard Chrome, Tungsten carbide, EN19 through hardness testing, surface roughness analysis, SEM, and EDS, XRD, sliding wear experiments and statistical study through Design of Experiment has been performed to find out the best material which can increase the life of rolls. From the experiments carried out it has been found that hardchrome has 15.19 times the longevity of the substrate EN19. Tungsten carbide has 19 times the life of EN19 and 1.25 times the life of hardchrome. Tungsten carbide coating gives more hardness and wear resistance than the Hard Chrome and EN19 base material of the roll. Thus, using Tungsten carbide coating on EN19 rolls will improve the life and enhance the longevity of the roll used in cold rolling process in heavy steel industry.