Abrasive wear behavior in dry condition of a plasticity-induced transformation steel

Abstract

The microstructural, mechanical, and tribological evaluation was carried out through an abrasion test of low alloy steel: 0,21%C, 1,22%Mn, and 2,16%Si with/without heat treatment. The steel was manufactured in an electric induction furnace from AISI-1018 steel with additions of FeMn and FeSi. Later it was hot rolled and heat treated. The microstructure of steel without heat treatment is ferritic-pearlitic with σ u = 714 MPa, S = 8%, and a hardness of 21 HRC. The microstructure of the heat-treated steel corresponds to a Plasticity Induced Transformation (TRIP) steel with σ u = 890 MPa, S = 30%, and hardness of 22 HRC. Both types of steel were subjected to abrasive wear (ASTM G-65) with silica sand particles and loads of 45, 66,5, and 130 N. The TRIP effect (transformation of retained austenite into martensite during plastic deformation) was evaluated before and after the tensile test by x-ray diffraction analysis. The results of the abrasion tests showed that the TRIP steel did not present high resistance characteristics, however, it shows better performance than steels with high carbon and/or alloy contents. The results show that with 45 N the TRIP steel is less resistant than the ferritic-pearlitic steel, however, with 66,5 and 130 N, its abrasive wear performance improved by 17% concerning the ferritic-pearlitic steel, which is attributed to the deformation capacity of TRIP steel. The main wear mechanisms present in TRIP steel are: ploughing, fractures, plastic deformation, pits, cracks, cutting, and micro-cutting. On the other hand, the surface hardness in the abrasion test footprint did not show any change that could be related to the TRIP effect. The microstructure analysis reveals that the material’s detachment occurs at the grain boundaries of the ferrite, in which the cracks that cause the detachment of the material were generated and propagated.