镁合金压铸件化成后表面白斑形成机理
The Forming Mechanism of the White Spot on the Chemical Conversion Coating of the Die-Casting Magnesium Alloy

作者: 韩民杰 :中北大学材料科学与工程学院; 刘宝胜 :太原理工大学材料科学与工程学院;

关键词: 镁合金耐蚀性化成白斑Magnesium Alloy Corrosion Resistance Chemical Conversion White Spot

摘要:
本文研究了镁合金压铸件化成处理后表面白斑形成机理,对其形态和组织进行了SEM及金相显微观察,并对其表面进行了粗糙度分析试验。结果表明:异型大块α相是白斑形成的主要原因,而白斑出现的本质是在压铸过程中,由于模具表面温度不一致,使得铸件表面形成粗大的先析α改变喷涂离型剂方法可消除此种不良现象。

Abstract:
The forming mechanism of the white spot of the die-casting magnesium was investigated by means of SEM andOM.The roughness of the white spot was also tested. It indicated that the larger α phase caused by the uneven temperature distribution of the die result in the formation of the white spot. It can be improved by changing the agent spaying parameter.

文章引用: 韩民杰 , 刘宝胜 (2013) 镁合金压铸件化成后表面白斑形成机理。 材料科学, 3, 99-102. doi: 10.12677/MS.2013.32019

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