A test methodology for the determination of wear coefficient

Wear coefficient values obtained from different investigators can vary significantly up to a deviation of 1000% due to lack of a standard test method. Higher wear coefficient values can be obtained when the wear tests are carried out within the transient wear regime, or with an excessive sliding distance in the steady-state wear regime. It is also difficult to judge whether the steady-state wear regime has been reached in conducting the wear test. A test methodology is therefore proposed in this paper to enable the wear coefficient to be determined more accurately, consistently, and efficiently. In this proposal, the wear test will be divided into three stages: (i) to conduct the transient wear test; (ii) to predict the steady-state wear coefficient with the required sliding distance by using the second wear coefficient equation proposed by Yang; and (iii) to conduct the steady-state confirmation runs to obtain the measured steady-state wear coefficient value. Based on the wear data obtained previously from aluminium based matrix composite materials, the average deviation between the predicted and measured standard steady-state wear coefficient values is found to be about 20%. The proposed methodology is found capable of saving about 40% of testing time if only the confirmation run at the predicted sliding distance is chosen.