Abstract A robber wheel abrasion tester with some advantages over the design described in ASTM 065 has been designed and characterised. In the new design the specimen was held horizontally. It was therefore possible to determine the actual mass flow rate of abrasive abrading the specimen and consequently the number of particles in the contact zone and the load carried by each particle. The abrasive feed system was designed to improve control over the conditions in the contact region. The performance of the apparatus was evaluated in tests on low carbon(AiSI 1020) steel, with wheels made from cast polyurethane and chlorobutyl rubber. The influences of load, sliding speed and robber hardness were investigated. Temperature rises of wheel, specimen and sand, and the friction force were measured; the main mechanism of heat dissipation was through the continual flow of fresh abrasive past the specimen. TE 65 多元砂/輪磨損試驗機