Influence of austenitising temperature on micro-scale abrasive wear of Ni-modified ferritic stainless steel

Abstract

The biofuel industry seeks materials that can reduce maintenance costs and enhance product quality. Low alloy ferritic stainless steel, specifically P410D with 11%wt Cr, 0.01%wt C, and 0.3%wt Ni, shows promise due to its superior wear-corrosion resistance compared to structural carbon steel. Maintaining corrosion resistance while improving mechanical strength is crucial for this sector. This study investigates the impact of austenitising temperature on the abrasive wear resistance of P410D ferritic stainless steel + nickel. Austenitising temperatures from 850°C to 1050°C were tested, followed by air quenching. Additionally, the annealed and 1050°C austenitised samples were field-tested in a biofuel industrial setting to observe real-world wear micromechanisms. Alongside laboratory evaluations using a fixed-ball micro-scale abrasive wear test, were conducted. SEM images revealed grooving as the predominant wear micromechanism due to abrasive particle sliding. Samples austenitised below 950°C exhibited a biphasic microstructure of martensite and ferrite, with properties dependent on martensite fraction. Temperatures above 950°C resulted in a fully martensitic microstructure. The heat treatment increased hardness by 78%, yield strength by 117%, and decreased ductility by 169%. The sample austenitised at 1050°C showed the lowest wear rate in both field and laboratory tests, with a 77% increase in abrasion resistance. Laboratory tests confirmed a positive correlation between wear resistance and austenitising temperature. Optimizing austenitising temperature thus enhances the abrasive wear resistance of P410D ferritic stainless steel, making it a viable material for the biofuel industry.