Solid Particle Erosion Studies of Weld Hardfacing Deposits

Abstract

Solid particle erosion studies were carried out on five commercial weld hardfacing alloys deposited by manual metal arc and flux cored arc-welding methods. These alloys were low and high chromium cast irons, which are widely used in cement plants, steel industries and mining industries for protection against wear by erosion. Erosive wear tests were conducted using industrial erodents like cement clinker, blast furnace sinter and silica sand, (all erodents having a particle size of 125-150 µm) at a velocity of 50 ms−1 and at impingement angles between 15 and 90°. A low alloy steel in weld deposited form was used as the reference material for comparison. The dependence of velocity on erosion rate was also established using these erodents. The results indicate that the erosion resistance of hardfacing alloys strongly depends on the relative hardness of erodents. The erosion resistance of high chromium iron was found to be twenty times, seven times and two times as that of low alloy steel, when eroded with cement clinker, blast furnace sinter and silica sand, respectively at an impact angle of 30°. The solid particle erosion resistance of these hardfacing alloys is discussed in relation to relative hardness, microstructural features and ability of erodents to cause gross fracture of carbides. The erosion rate showed power-law dependence on velocity, expressed by the relationship, E = kVn, where k is a constant and n depends upon material and erosion conditions.