Evaluation of erosive-abrasive wear resistance of Fe-19 %Cr-1.9 %C high chromium cast iron using an impeller-tumbler test device

Abstract

High chromium cast irons (HCCIs) are commonly used by the mining industry which high wear resistance are required. One of its applications is in iron ore pellets chutes, where plates used to protect the equipment under go high wear rates. However, since chromium content used in HCCI has large influence on the parts costs, it is important to ensure that the heat treatments applied are appropriate for each alloy composition. The present study evaluated the influence of temperature and time of austenite destabilization on the hardness and wear resistance and identified the wear mechanisms found in the experiments. The samples were subjected to temperatures of 900, 1000, and 1100 °C for 30 min and then cooled at air. Wear tests were done using tumbler impeller tribometer, equipment capable of simulating a tribo system. The results showed that the destabilization heat treatmentat 900 °C and 30 min with air cooling has better results in terms of wear resistence and hardness due to the new microstructure formed mainly by martensite and small secondary carbides dispersed in the matrix.