Abstract
AZ91 alloy powders produced by gas atomization were consolidated by hot-rolling. The obtained AZ91 alloys have a density more than 98% of that of the ingot alloy when rolled to 70% reduction and at a temperature above 623K. The decrease of rolling temperature from 723 to 523K increases a hardness from 95 to 110HV, and reduces a friction coefficient and wear depth, resulting in the improvement of wear properties. The tensile strength of 330 MPa is obtained for the sample rolled at a temperature above 623 K. On the other hand, the consolidation at a temperature below 623 K causes the generation of cracks during hot-rolling and decrease a tensile strength. It is expected that an optimization of rolling condition at temperatures below 623 K would inhibit the generation of cracks, leading to the improvement of tensile strength.
