Effect of the Addition of Zn on the Microstructure and Mechanical Properties of 5083 Alloy

In this work, the effect of alloying element Zn on microstructure and prosperity of 5083 Al alloy was investigated. The grain sizes of 5083 and 5083 + Zn alloys were refined to <200 nm by appropriate rolling processes. The microhardness and tensile tests were conducted. The results showed that the dislocation density evaluated by microhardness of rolled 5083 + Zn alloys increases from 1.90 × 1013 to 2.57 × 1013 with increasing Zn contents. The tensile tests showed that the ultimate tensile strength of rolled 5083 alloy doubled when Zn was introduced, while the uniform elongation pronounced decreased. The yield strength of 5083 + Zn alloys increases with Zn contents. However, the strain hardening rate for the rolled alloys was decreased with increasing Zn contents. Solid solution strengthen and precipitation strengthen due to addition of Zn were responsible for the increase in yield strength and ultimate tensile strength.