稀土元素Ce对石墨球化作用的研究  

Investigation of the Effect of Rare-earth Element Ce on Graphite Spheroidization

作　　者：石丽敏[1] 朱定一[1] 罗晓斌[1] 

机构地区：[1]福州大学材料科学与工程学院,福建福州350002

出　　处：《铸造技术》2008年第10期1364-1368,共5页Foundry Technology

基　　金：国家自然科学基金资助项目(50471007);福建省自然科学基金资助项目(E0710006)

摘　　要：通过凝固过程中的热分析试验,研究了稀土元素Ce对Ni-C二元过共晶合金凝固过程中过冷度及石墨生长形态的影响。结果表明,加入稀土元素Ce,初生相石墨结晶时的过冷度显著增大,凝固组织中的石墨形态由片状生长转变为球状生长;但加入Ce后,若提供一个小的过冷条件,石墨将以片状形态生长,表明凝固时的过冷是促进石墨球状生长的主要因素;稀土元素Ce并非是石墨球化的充分条件。Thermal analysis test was adopted to investigate the effects of rare-earth element Ce on the degree of undercooling and the morphology of graphite growth during the solidification process of the hypereutectic Ni-C alloy. It is indicated that Ce addition significantly increases degree of undercooling of primary graphite, and the morphology of graphite changes from flake to sphere. However, if a small undercooling is given, the graphite grows in flake form after adding Ce. The experiment result shows that undercooling is a primary factor that promotes graphite to grow in spherical form during the solidification, and rare-earth element Ce is not sufficient condition for graphite spheroidization.

关 键 词：Ni-C合金 球化机理 过冷 热分析 

分 类 号：TG255[金属学及工艺—铸造]