Journal Article

Microstructure and mechanical properties of Si and Sb added AZ91 magnesium alloy

Srinivasan, A., Pai, B. C., Pillai, U. T. S.

2005

Overview

The effect of Si (individual and combined) with 0.2 pct Sb additions on the microstructure and mechanical properties of permanent mold AZ91 alloy has been studied. The results indicate that Si addition introduces a Chinese script Mg^sub 2^Si phase at the grain boundary along with the Mg^sub 17^Al^sub 12^ -β phase and reduces ductility and strength of the alloy both at room and high temperatures. A small amount of Sb addition modifies the Mg^sub 2^Si phase besides distributing it evenly along the grain boundary. Improved room- and high-temperature mechanical properties are observed in Sb added AZ91 + xSi alloys. However, maximum properties are noticed with the alloy having the combined addition of 0.2 silicon and antimony. Fractograpy of tensile- and impact-tested AZ91 alloy shows cleavage and brittle type of failure. Addition of Si reduces the quasi-cleavage planes, whereas Sb addition increases it while also increasing the plastic zone. [PUBLICATION ABSTRACT]

• Publisher: Springer,Springer Nature B.V
• Subject: Alloys / Applied sciences / Exact sciences and technology / Magnesium / Materials science / Mechanical properties / Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology / Metals. Metallurgy / Microstructure / Silicon