THE PROCEDURE OF SELECTING THE VALUES OF THE WORK CONDITION PARAMETERS OF THE BALL-CRATERING METHOD FOR THE ASSESSMENT OF RESISTANCE TO ABRASIVE WEAR

In the example of the CrN coating deposited by the cathodic arc evaporation (CAE) method on two differently prepared substrates, the procedure for selecting the values of the work condition parameters of the ballcratering method was presented. The procedure was developed thanks to applying an individual experiment design from Taguchi's approach and has not been used to determine the values of the parameters of the operating conditions of the test friction node for tribological tests. The procedure, according to Taguchi, allowed us to determine the values of the parameters for assessing the abrasion resistance of anti-wear coatings, with the use of a much smaller number of tests, compared to the methods used so far and a repetitive wear mechanism. The starting point of the presented procedure was selecting the area of the permissible values of the operating parameters, in the ball-cratering method, in which optimal values were searched for to minimise the relative error in determining the diameters of wear marks craters. After determining the area of limit values, an experiment plan was generated in which the variables were: load, rotational speed, minimum friction path, and maximum friction path. The results of abrasive wear tests performed with the ball-cratering method, in accordance with the developed test procedure for the CrN coating – were deposited on the substrate after heat treatment and the substrate after the nitriding process had been successfully verified.