半固态浆料的影响(Ⅱ)
(1. 兰州理工大学 甘肃省有色金属新材料省部共建国家重点实验室，兰州 730050；
2. 兰州理工大学 有色金属合金及加工教育部重点实验室，兰州 730050)
摘 要: 采用加入与母合金液具有相同成分的自孕育剂方法，研究孕育剂参数(孕育剂加入方式、孕育剂尺寸、孕育剂加入量和孕育剂组织)对AM60镁合金组织细化的影响。结果表明：加入自孕育剂后，熔体经导流器浇注到铸型中，可以明显细化AM60镁合金的组织。当孕育剂加入量为11%(质量分数)时，效果最好，平均晶粒尺寸仅为43.4 μm，且分布均匀。孕育剂的原始组织对合金凝固组织有明显的影响，孕育剂本身的组织越细小，合金凝固组织越细小。孕育剂的加入使合金液中形成大的能量起伏和成分起伏，在合金凝固过程中起到吸热、形核、促进凝固和阻止二次相连续长大的作用，有助于形成细晶组织。
关键字: AM60镁合金；孕育剂；自孕育法；组织细化；半固态
semisolid slurry prepared by self-inoculation method (Ⅱ)
（1. State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials,
Lanzhou University of Technology, Lanzhou 730050, China;
2. Key Laboratory of Non-ferrous Metal Alloys and Processing,
Ministry of Education, Lanzhou University of Technology, Lanzhou 730050, China）
Abstract:The self-inoculant with the same composition as the melt of alloy was introduced into the melt. The effects of the inoculant parameters, such as addition method, particle size, addition amount and precursor microstructure, on grain refinement were investigated. The results indicate that the grain size of AM60 alloy is refined when the self-inoculant is introduced into the melt, and then the melt passes through a special cooling channel. A average grain size of 43.4 μm is gained when the addition amount of inoculants is up to 11% (mass fraction). The precursor microstructure of self-inoculants affects final solidification microstructure visibly of AM60 alloy. The smaller the microstructure of self-inoculant is, the better the final solidification microstructure is. The inoculant increases the thermal and constitutional fluctuation, and plays a role of heat absorption, nucleation, acceleration solidification during solidification of AM60 alloy, which is helpful for the formation of grain refining microstructure.
Key words: AM60 magnesium alloy; inoculant; self-inoculation method; grain refinement; semi-solid state
