High stress abrasive wear behavior of coal mill liner materials – A model based factorial design

In the present investigation, high stress abrasive wear behavior of the liner materials commonly used in coal fired thermal power plants was simulated by performing two body abrasion tests on as-received nihard 4 (NH-4), super nihard (SNH) and high chromium cast iron (HCCI) materials. The abrasion tests were conducted within a specific experimental parametric domain. Modeling of data has been carried out using multiple linear regression technique for each material, using two level factorial design methodology. The utility of the proposed model was established by validating the predicted wear results with the corresponding experimental observations. It was observed that the predicted wear results obtained from multiple regression model were in good agreement with the two body abrasion test results under simulated conditions. Owing to its high hardness HCCI showed better abrasion resistance in comparison to that of NH-4 and SNH, which is primarily due to the uniform distribution of hard M₇C₃ carbides within the austenite/martensite matrix.