Improvement of wear scar volume estimation in reciprocating motion

Abstract

Reduction of errors in wear measurement is a task of great functional significance. Reciprocating testers are commonly used to study the wear of engineering materials. However, the estimation of wear scar volume based on only one cross section for strokes smaller than 2.5 mm, proposed in the standard, often leads to incorrect results. In this work, the results of the measurement of 70 steel samples were analysed using a white light interferometer. The strokes were between 0.1 and 2 mm. The results achieved using areal (3D) surface topography measurement were treated as reference. It was found that the use of the standardised method caused an overestimation of the wear volume of up to 27.2 %; the average error was 13.9 %. The improvement of this method based mainly on measurement of three profiles perpendicular to the wear scar in its central part and near the round edges within the stroke led to reduction of maximum errors to 14.1 % and of average errors to 4.5 %. The criterion of the necessity of using the improved procedure of approximation of the volume of the wear scar was proposed.