半固態(tài)漿料的影響(Ⅱ)
(1. 蘭州理工大學 甘肅省有色金屬新材料省部共建國家重點實驗室，蘭州 730050；
2. 蘭州理工大學 有色金屬合金及加工教育部重點實驗室，蘭州 730050)
摘 要: 采用加入與母合金液具有相同成分的自孕育劑方法，研究孕育劑參數(孕育劑加入方式、孕育劑尺寸、孕育劑加入量和孕育劑組織)對AM60鎂合金組織細化的影響。結果表明：加入自孕育劑后，熔體經導流器澆注到鑄型中，可以明顯細化AM60鎂合金的組織。當孕育劑加入量為11%(質量分數)時，效果最好，平均晶粒尺寸僅為43.4 μm，且分布均勻。孕育劑的原始組織對合金凝固組織有明顯的影響，孕育劑本身的組織越細小，合金凝固組織越細小。孕育劑的加入使合金液中形成大的能量起伏和成分起伏，在合金凝固過程中起到吸熱、形核、促進凝固和阻止二次相連續(xù)長大的作用，有助于形成細晶組織。
關鍵字: AM60鎂合金；孕育劑；自孕育法；組織細化；半固態(tài)
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
