On the grain refining of magnox by powder extrusion

Abstract

This is to report on a comparative study on the micro-structure and properties of Magnox powder extrusion (Mg-1%Al-0.015%Be) with 0%, 20% and 40% of Mg-0.6%Zr powder and cast-billet extrusion. The findings are as follows:
(1) The grain size of powder extrusion is finer than that of the cast billet extrusion. The addition of Mg-0.6%Zr inhibits the grain growth and, consequently, increases the strength of extrusions in the state of as-extruded as well as of annealed.
(2) The more addition of Mg-0.6%Zr, the less corrosion resistance at elevated temperature. But under the temperature of 450°C, the powder extrusion of Magnox with Mg-0.6%Zr keeps sufficient corrosion resistance.