微合金化铝铁合金的强化机理

Strengthening Mechanism of Micro Alloying of Al-Fe Alloy

微合金化铝铁合金中,随着Sc、Zr元素的加入,合金熔体中形成Al-Fe、Al-Sc、Al-Zr、Al-Fe-Sc、Al-Fe-Zr、Al-Fe-Sc-Zr固溶体,起到了固溶强化的作用,合金的强度、硬度提高,塑性、韧性降低。Sc、Zr细化剂在凝固过程中提供优质的异质形核核心,有效地细化铝基体晶粒。并且在一定程度上改变富铁相形态,使之由粗针状逐渐转变成细针状和花朵状,起到细晶强化的作用,进一步改善合金的综合力学性能。

In the micro alloying of Al-Fe alloy, Al-Fe, Al-Sc, AI-Zr, Al-Fe-Sc, AI-Fe-Zr and Al-Fe-Sc-Zr solid solution appear along with the addition of the elements of Sc and Zr, which can play a strengthening effect on the solid solution of the alloy, and the strength and hardness increase, but the plasticity and toughness decrease. The grain of the aluminum matrix is effectively refined when the refining agent provides high quality heterogeneous nucleation core in the process of alloy solidification. The iron rich phase phase partly changes from the shape of coarse needles to be fine needle-like and flower-like. It also plays a strengthening effect on the refining agent and improve the comprehensive mechanical properties of the alloy.