Influence of microstructure on the corrosion of diecast AZ91D
Influence of microstructure on the corrosion of diecast AZ91D
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DOI：
10.1016/s0010-938x(98)00121-8
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发表时间：
1999-02-01
影响因子：
8.3
通讯作者：
Dargusch, M
中科院分区：
文献类型：
--
作者：
Song, GL;Atrens, A;Dargusch, M
研究了压铸AZ91D的腐蚀并与其微观结构相关。为了进行比较并更全面地了解压铸 AZ91D 的行为，还使用缓慢凝固的高纯度 AZ91、Mg-2%Al、Mg-9%Al、低纯度镁和高纯度镁进行了腐蚀研究和微观结构检查。通过 (1) 观察腐蚀形态，(2) 测量电化学极化曲线，以及 (3) 同时测量析氢速率和镁溶解速率，研究了 pH 11 的 1N 氯化钠中的腐蚀。压铸AZ91D的表皮比内部表现出更好的耐腐蚀性。这归因于以下因素的组合：(1) β 相的体积分数更高，(2) 更细的 α 晶粒周围的 β 相分布更连续，以及 (3) 表层中的孔隙率低于压铸件内部的孔隙率。这项研究表明，铸造方法可以通过影响合金微观结构来影响腐蚀性能。 (C) 1999 Elsevier Science Ltd. 保留所有权利。
The corrosion of die cast AZ91D was studied and related to its microstructure. For comparison and to more fully understand the behaviour of die cast AZ91D, corrosion studies and microstructural examinations were also carried out using slowly solidified high purity AZ91, Mg-2%Al, Mg-9%Al, low purity magnesium and high purity magnesium. Corrosion was studied in 1N NaCl at pH 11 by (1) observing the corrosion morphology, (2) measuring electrochemical polarisation curves and (3) simultaneously measuring both the hydrogen evolution rate and the magnesium dissolution rate. The skin of die cast AZ91D showed better corrosion resistance than the interior. This is attributed to a combination of(1) a higher volume fraction of the beta phase, (2) a more continuous beta phase distribution around finer alpha grains, and (3) lower porosity in the skin layer than in the interior of the die casting. This study showed that the casting method can influence the corrosion performance by its influence on the alloy microstructure. (C) 1999 Elsevier Science Ltd. All rights reserved.