Comparative Wear Rate Evaluation of Zinc Aluminum (ZA) and Bronze Alloys through Block on Ring Testing and Field Applications

A first order evaluation of wear rate and friction characteristics of sand cast, permanent molded, pressure die cast and continuously cast ZA alloys has been made, using a Block on Ring test configuration, conducted under oil lubrication conditions. Two commonly used bronze bearing alloys were also studied using the same experimental conditions.

In general, sand cast ZA alloys displayed the highest wear resistance, followed by pressure die cast and permanent molded alloys, with concast material showing the highest wear rate. It was found that ZA alloys out-performed C93200 (SAE 660) leaded bronze in all cases, whereas C95200 Al bronze (SAE 9A) displayed the highest wear resistance, equivalent to that of sand cast ZA-27. These results are discussed in the light of field trials and actual components in service.