Tribological study of fourth-stage crusher coatings applied in an iron ore processing plant

Abstract

In the present work, a tribological study was carried out on concave and mantle linings of cone crushers used in the fourth-stage crushing process of an iron ore processing plant. Initially, an analysis of the characteristics over the lifetime of the applied coatings was carried out, and samples of the parts that suffered the most critical wear were selected to carry out the tribological study. Investigation of the wear mechanism and deformation was performed via microhardness analysis, optical microscopy (OM), and scanning electron microscopy (SEM) measurements. The mantle and concave were composed of the same alloy, austenitic manganese steel with 12% Mn. Abrasion tests in the rubber wheel configuration were performed on the mantle and concave samples, and the results were compared with those of two other commercial alloys of manganese steel (one with 18% Mn and one with 18% Mn and 2.5% Cr). It was observed that concave wear occurs differently from mantle wear. While the concave suffers more indentation, the mantle has a more abrasion-dominant profile. This analysis is of paramount importance for conducting a review of the maintenance strategy. The mantle presented less work hardening and a higher wear rate than the concave. The predominant wear mechanism is abrasion. Austenitic manganese steel with 18% Mn and 2.5% Cr presented high abrasive wear resistance, with a wear rate 18% lower than that of the alloy used in the manufacture of cone crusher linings. Higher hardness values result in a lower wear rate, and the use of austenitic manganese steel with 18% Mn and 2.5% Cr represents an opportunity to increase the useful life of cone crusher linings.