【摘要】：采用SEM,EPMA,TEM和硬度測試等技術(shù),研究2E12鋁合金鑄錠在均勻化過程中的非平衡相溶解、元素分布特征以及第二相析出行為。研究結(jié)果表明:合金鑄錠的晶界處連續(xù)分布著粗大的α+θ+S共晶組織。合金中的Cu和Mg元素存在明顯的偏析,而Mn元素分布較為均勻。隨著均勻化處理的進(jìn)行,合金中的粗大共晶組織逐漸溶解,Cu,Mg和Si元素逐步溶入合金基體,而Fe和Mn元素則從合金基體中脫溶。在均勻化處理過程中,合金基體中析出大量T相粒子。伴隨著T相的析出,合金的硬度逐漸升高,同時電導(dǎo)率也明顯增加。當(dāng)合金于490℃均勻化1 000 h后,晶界附近出現(xiàn)明顯的PFZ。
[Abstract]:SEM,EPMA,TEM and hardness testing techniques were used to study the dissolving of non-equilibrium phase, the distribution of elements and the precipitation behavior of the second phase in 2E12 aluminum alloy ingot during homogenization. The results show that the coarse 偽 胃 S eutectic structure is continuously distributed at the grain boundary of the alloy ingot. The Cu and Mg elements in the alloy are segregated obviously, while the distribution of Mn elements is more uniform. With the homogenization treatment, the coarse eutectic structure of the alloy gradually dissolved, the elements of Cu,Mg and Si gradually dissolved into the alloy matrix, while the elements of Fe and Mn dissolved from the alloy matrix. During homogenization, a large number of T phase particles were precipitated from the alloy matrix. Along with the precipitation of T phase, the hardness and conductivity of the alloy increased gradually. When the alloy was homogenized at 490 鈩，

本文編號：2273758