摘要
某厂用AZ91D镁铝合金生产的手提计算机机壳 ,经精密铸造而成。在放置一段时间后 ,常常发生爆痘现象 ,用扫描电镜和红外光谱分析了这一现象。结果表明 ,氧化镁夹杂存在于镁铝合金中 ,它可以逐渐吸收空气中的水分 ,转变为氢氧化镁 ,发生极大的体积膨胀 ,从而引起爆痘。减少爆痘的根本方法是降低或消除MgO夹杂物的含量。
A kind of pocket computer casing, made of AZ91D alloy, is manufactured by precision casting. When the computer casing was kept for some time, it was found that there were some smallpoxes on the surface of the casing. In the paper, the formation mechanism of the smallpoxes was investigated by means of scanning electron microscope and infrared spectrometer. It is concluded that MgO inclusions in Mg-Al alloy is an important factors which leads to formation of smallpoxes. MgO turns into Mg(OH) 2 by absorbing water in the air. Because of difference of density between MgO and Mg(OH) 2, volume expansion takes place inevitably. A basic way of reducing smallpoxes is to cut down content of MgO inclusions.
出处
《兵器材料科学与工程》
CAS
CSCD
2004年第1期39-41,共3页
Ordnance Material Science and Engineering
基金
山西省自然科学基金项目 ( 2 0 0 110 44 )
