摘要
建立了镁合金的晶体,液态及其固/液界面模型.采用递归法计算了Ca,Be在α-Mg、固/液界面、镁液态中的环境敏感镶嵌能,定义并计算了Mg,Ca及Be与氧的原子亲和能.计算结果表明:Ca,Be在镁晶体中的环境敏感镶嵌能较高,不能稳定固溶于晶体中,因此在固体中的溶解度较小.合金凝固时Ca,Be扩散到环境能较低的液体中,向液面聚集.由于Ca,Be与氧的原子亲和能低于镁与氧的亲和能,聚集在液体表面的Ca,Be将优先与氧结合,生成致密的镁与合金元素的混合氧化物,阻止镁合金燃烧.
The atomic cluster models of a-Mg,liquid Mg and the interface between liquid/solid have been founded. The environmentsensitive embedding energy of Ca and Be in α-Mg, liquid Mg, liquid/solid interface has been calculated by recursion method. The atomic affinity energy between Mg, Ca, Be with O has been defined and calculated. The calculated results show that the solid solubility of Ca and Be is very small in α-Mg, because of their higher environment-sensitive embedding energy leads to instability in α-Mg crystal. The Ca and Be diffuse in to the liquid Mg, which has lower environment-sensitive embedding energy than the solid,and congregate on the surface of liquid Mg as the alloys solidify. Because the atomic affinity energy of Ca-O and Be-O is lower than Mg-O, The Ca and Be aggregating on the surface of liquid Mg will priorly combined with O, forming compact oxides of Ca, Be and alloys of elements, which prevent Mg alloys from burning.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2009年第5期3315-3318,共4页
Acta Physica Sinica
基金
国家自然科学基金(批准号:50671069)
辽宁省教育厅科学研究计划(批准号:2008511
20060807
2007T165)
沈阳市科技计划基金(批准号:1072026100)资助的课题~~
关键词
电子结构
阻燃
MG合金
electronic structure, ignition-proof, Mg alloys
