Investigations on Microstructure and Mechanical Properties of AZ91 Alloy Processed by Single Pass Rolling with Varied Rolling Reductions

Abstract

In this study, single pass rolling (SPR) with varied rolling reductions was conducted on pre-homogenized AZ91 alloys (H alloys) and ECAP-processed AZ91 alloys (HE alloys). The effects of rolling reduction on the microstructures and mechanical properties of HR alloys (pre-homogenized and rolled) and HER alloys (ECAP-processed and rolled) were investigated. The results showed that the HER alloys possessed much finer microstructures and superior mechanical properties than the HR alloys, which were significantly influenced by the rolling reduction. The microstructures of the HER alloys became bimodal, and the strength and elongation markedly improved with the increase in the rolling reduction. When the rolling reduction reached 70%, the HER alloys acquired a typical bimodal structure, contributing to their excellent comprehensive mechanical properties.