Effect of microstructure, impact velocity and angle on erosive wear of medium carbon, dual phase and fully martensitic steels

Abstract

The present study has been conducted to analyze the effect of microstructure on erosive wear of medium carbon (N), dual phase (DP) and fully martensitic (FMS) steels at different velocities (30 m/s, 60 m/s, 90 m/s and 120 m/s) and impingement angles (15°, 45°, 75°, and 90°) with Al2O3 as an erodent. The findings suggest that the steady state erosion rate increases with an increase in impact velocity for all materials, whereas it decreases with an increase in impact angle for all steels except for FMS. At low and high impact angles, N steel exhibits the highest erosive wear characterized by micro cutting and ridge formation. Except at 90° and 120 m/s, FMS has shown the highest erosion rate compared to all steels due to its inherent brittle nature, which makes it prone to easy crack propagation. In DP steel, the cracks get arrested by the hard martensite island and their easy propagation is inhibited, which leads to only low angle cutting and micro ploughing. This reflects the advantage of using a dual phase structure. DP steels showed higher erosion resistance because they offer a balanced combination of strength and ductility at an adequate level of toughness. The material removal in N steel is found to occur by micro cutting, ridge, and crater formation, whereas shallow micro ploughing and craters are observed in FMS. However, the material removal for DP steels has been found to occur due to a combination of micro ploughing, micro cutting and crater formation.