Al_4C_3细化AZ91合金晶粒的现象和机理  

Giran refinement and mechanism of AZ91 alloy with Al_4C_3 addition

作　　者：王春建[1,2] 金青林[3] 蒋业华[3] 周荣[3] 

机构地区：[1]昆明理工大学分析测试研究中心,云南昆明650093 [2]云南省分析测试中心,云南昆明650093 [3]昆明理工大学材料科学与工程学院,云南昆明650093

出　　处：《材料热处理学报》2010年第11期12-17,共6页Transactions of Materials and Heat Treatment

基　　金：云南省自然科学基金(2007E031M)

摘　　要：通过向熔体中直接添加Al4C3颗粒,研究了Al4C3对AZ91合金的晶粒细化现象和机理的影响。结果表明,Al4C3颗粒对AZ91合金的晶粒细化效果与孕育参数直接相关,孕育温度越高孕育时间越久,Al4C3的细化效果越明显。研究发现,实验添加的Al4C3颗粒并没有直接成为镁的晶核,而是被推开到了晶粒生长界面前沿,Al4C3的细化作用主要是因为Al4C3发生了微量的溶解,从而向熔体中提供了碳,碳的存在对熔体起到了碳质孕育法处理的作用。Effect of Al4C3 particles on grain size of AZ91 alloy was investigated through adding Al4C3 into the alloy melts directly.It was shown that grain refining efficiency of Al4 C3 particles was influenced by inoculating conditions.The higher the melt temperature and the longer the holding time,the higher the grain refining efficiency of Al4 C3 particles.Al4 C3 particles didn＇t act as heterogeneous nucleuses directly but were pushed out in front of liquid /solid interface.The mechanism of grain refinement by Al4 C3 was attributed to the dissolution of a trace of Al4 C3 and the release of carbon.

关 键 词：镁合金 晶粒细化 异质形核 

分 类 号：TG146.2[一般工业技术—材料科学与工程]