Effect of zirconium on aluminium and its alloy (5th Report)

Effect of Mn, Fe and Cu on the recrystallization characteristics of Al-Zr alloys

Abstract

In the previous report, it was stated that Si and Mg as impurities in Al-Zr alloy give some influence to the effect of Zr of increasing the recrystallization temperature of aluminium.
In this report, the same influence is discussed about Mn, Fe and Cu.
1. Mn: Mn prevents the effect of Zr on the recrystallization temperature of aluminium. Through X-ray examination, it was found out that the reason why Mn prevents the above-mentioned effect of Zr is that Mn contained in Al-Zr alloy makes an intermetallic compound Mn₂Zr.
2. Fe: Like Mg, Fe does not prevent much the effect of Zr. Since it can not be observed through X-ray examination that such small amount of Fe as an impurity in Al-Zr alloy makes any intermetallic compound, it is considered the harm by Fe is negligible. But, when Fe is added to the alloy, it decreases the solubility of Zr into aluminium and increases the precipitation at the time of solidification. It is considered, therefore, Fe itself has a nature of preventing such effect of Zr as mentioned above.
3. Cu also prevents the effect of Zr, because, it is considered, it makes an intermetallic compound Cu Zr₂in Al-Zr alloy.