Influence of hydrogen content on the behavior of grain reflnement in hypereutectic aluminum-silicon alloy  

作　　者：LinaHu XiufangBian YoufengDuan 

机构地区：[1]KeyLaboratoryofLiquidStructureandHeredityofMaterialsoftheMinistryofEducationofChina,ShandongUniversity（SouthPart）,Jinan250061,China

出　　处：《Journal of University of Science and Technology Beijing》2004年第2期141-146,共6页北京科技大学学报（英文版）

基　　金：This work was financially supported by the National Natural Science Foundation of China (No.50071028);the Natural Science Foundation of Shandong Province in China (No. Z2001F02)

摘　　要：Dissolved hydrogen is harmful to mechanical properties of refinedhypereutectic aluminum-silicon alloys. In the present work, by using a stepped-form mold and thehydrogen-detecting instrument HYSCAN II, the relationship between the initial hydrogen content inthe melt and the refinement effect on the casting of hypereutectic aluminum-silicon alloy wasinvestigated. The experimental results show that the cooling rate, the hydrogen content and thegrain refinement effect are three interactive factors. When the hydrogen content is above 0.20mL/100 g and the cooling rate is lower than that in 50 mm-thick step, hydrogen dissolved in thealloy melt influences the grain refinement effect. With increasing the cooling rate, the criticalhydrogen content increases too. It is expected that much hydrogen in the melt make the netinterfacial energy larger than or equal to zero, resulting in the shielding of the particles AlPduring solidification and that the critical gas content is closely related to the critical radius ofembryo bubbles.Dissolved hydrogen is harmful to mechanical properties of refinedhypereutectic aluminum-silicon alloys. In the present work, by using a stepped-form mold and thehydrogen-detecting instrument HYSCAN II, the relationship between the initial hydrogen content inthe melt and the refinement effect on the casting of hypereutectic aluminum-silicon alloy wasinvestigated. The experimental results show that the cooling rate, the hydrogen content and thegrain refinement effect are three interactive factors. When the hydrogen content is above 0.20mL/100 g and the cooling rate is lower than that in 50 mm-thick step, hydrogen dissolved in thealloy melt influences the grain refinement effect. With increasing the cooling rate, the criticalhydrogen content increases too. It is expected that much hydrogen in the melt make the netinterfacial energy larger than or equal to zero, resulting in the shielding of the particles AlPduring solidification and that the critical gas content is closely related to the critical radius ofembryo bubbles.

关 键 词：REFINEMENT hypereutectic aluminum-silicon alloy phosphide AlP poreformation 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TF114[金属学及工艺—金属材料]