(1. 湘潭大学 材料设计及制备技术湖南省重点实验室 材料科学与工程学院，湘潭 411105；
2. 湖南省产商品质量监督检验研究院，长沙 410007)
摘 要: 通过扫描电子显微镜和能谱仪(SEM-EDS)以及X射线衍射仪(XRD)等研究不同含量的Mo、Cr和Si对Co-Mo-Cr-Si合金的组织及其700 ℃耐铝液腐蚀性能的影响。结果表明：在实验范围内，当w(Si)＜2.8%时，基体为FCC-Co；而当w(Si)≥2.8%时，基体转变为HCP- Co。随Mo和Si含量增加，Laves相比例增加。在本工作中CoMo4Cr23.8Si0.6合金耐腐蚀性能最好，但由于是单一的固溶体相，基体很软。具有高硬度的CoMo28.5Cr16.7Six合金随着Si含量的增加，其硬度随之增加，耐腐蚀性也随之提高，腐蚀产物主要是(Co,Mo,Cr)2Al9和(Cr,Mo)7Al45。Mo含量较多时主要生成(Mo,Cr)Al5，Cr元素含量较多时主要生成(Cr,Mo)2Al13。
关键字: Co-Mo-Cr-Si合金；组织；铝液腐蚀
（1. Key Laboratory of Materials Design and Preparation Technology of Hunan Province, School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China;
2. Hunan Testing Institute of Product and Commodity Supervision, Changsha 410007, China）
Abstract:By SEM-EDS and XRD and other means, the effects of Mo, Cr and Si on the microstructure and corrosion resistance of Co-Mo-Cr-Si alloys in liquid aluminum at 700 ℃ were investigated. The results show that, when w(Si)＜2.8%, the crystal structure of (Co) is FCC; when w(Si)≥2.8%, the crystal structure of (Co) is transformation to HCP. Laves phase ratio increases with the increase of Mo and Si content. Alloy CoMo4Cr23.8Si0.6 has the best corrosion resistance, but it is not hard because of single solid solution matrix. The hardness and corrosion resistance of CoMo28.5Cr16.7Six alloy enhances with the increase of Si content, the corrosion products are mainly (Co, Mo, Cr)2Al9 and (Cr, Mo)7Al45. When the content of Mo is high, the main compound is (Mo,Cr)Al5. When the content of Cr is high, the main compound is (Cr, Mo)7Al45.
Key words: Co-Mo-Cr-Si alloys; microstructure; molten aluminum; corrosion
