【摘 要】
：
本文制备了不同Fe和Mn含量高真空压铸AlSiMgMn合金,使用透射电镜(TEM)对富Fe相晶体结构和成分进行了分析;使用高分辨三维X射线(3Dμ-CT)对合金进行了断层扫描,获得了富Fe相三维形貌和空间坐标;结合非平衡凝固相变计算,讨论了Fe和Mn含量对富Fe相形成的影响,并分析了初生α-Fe相的生长机理.基于二分Kmeans和DBSCAN方法,设计了空间粒子团簇计算程序,对3Dμ-CT得到的富Fe金属间化合物进行了聚类计算,分析了其团簇定量特征.结果表明:随着Fe含量增加,富Fe相中Fe含量增加;Mn
【机 构】
：
华南理工大学 国家金属材料近净成形工程技术研究中心,机械与汽车工程学院,广州 510640
论文部分内容阅读
本文制备了不同Fe和Mn含量高真空压铸AlSiMgMn合金,使用透射电镜(TEM)对富Fe相晶体结构和成分进行了分析;使用高分辨三维X射线(3Dμ-CT)对合金进行了断层扫描,获得了富Fe相三维形貌和空间坐标;结合非平衡凝固相变计算,讨论了Fe和Mn含量对富Fe相形成的影响,并分析了初生α-Fe相的生长机理.基于二分Kmeans和DBSCAN方法,设计了空间粒子团簇计算程序,对3Dμ-CT得到的富Fe金属间化合物进行了聚类计算,分析了其团簇定量特征.结果表明:随着Fe含量增加,富Fe相中Fe含量增加;Mn含量增加不改变富Fe相的元素含量;两者均不改变富Fe相的晶格常数,但大幅提高富Fe相的形成温度;与平衡凝固相比,高冷却速度下富Fe相和α(Al)相形成顺序改变,对富Fe金属间化合物三维特征和分布产生重要影响,其团簇更为紧密.
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