稀土元素Eu和冷却速率对Al-7Si合金中共晶硅的影响  

Effect of Rare Earth Element Eu and Cooling Rate on Eutectic Silicon in Al-7Si Alloy

作　　者：欧黎明 毛丰 乔永枫 高梦锞 吴修德[1] 魏世忠[2] OU Liming;MAO Feng;QIAO Yongfeng;GAO Mengke;WU Xiude;WEI Shizhong(School of Mechanical Engineering,Yangtze University,Jingzhou 434023,China;National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials,Henan University of Science and Technology,Luoyang 471003,China)

机构地区：[1]长江大学机械工程学院,荆州434023 [2]河南科技大学金属材料磨损控制与成型技术国家地方联合工程研究中心,洛阳471003

出　　处：《材料导报》2021年第8期103-107,共5页Materials Reports

基　　金：河南省重点研发与推广专项(192102210009);江苏省高端结构材料重点实验室开放基金(hsm103);金属材料磨损控制与成型技术国家地方联合工程研究中心(HKDNM201815)。

摘　　要：针对稀土元素Eu对共晶硅有良好的变质效果,本工作研究了不同Eu含量(0.04%、0.1%、0.16%、0.22%,质量分数,下同)、冷却速率、变质温度、保温时间以及重熔次数对Al-7Si中共晶硅的变质效果的影响。结果表明:冷却速率的提高有利于Eu元素对光晶硅的变质,冷却速率越高,共晶硅由针片状完全转变为纤维状所需加入的Eu越少;变质温度和保温时间会影响Eu元素对共晶硅的变质效果,最佳的变质温度为750℃,最佳的保温时间为15 min;重熔次数的增多,将致使变质失效,在不影响稀土Eu变质效果的情况下,重熔次数应不超过三次。In view of the good modification effect of rare earth element Eu on eutectic silicon,this paper investigates the effects of different Eu content(0.04%,0.1%,0.16%,0.22%,wt%),cooling rate,modification temperature,holding time and remelting times on the modification effect of Al-7 Si eutectic silicon.The results show that the increase of cooling rate is beneficial to the modification of Eu element.The higher cooling rate is,the lower the Eu content is required for the complete transformation of eutectic silicon from needle to fibrous.The modification temperature and holding time will affect the modification effect of Eu element.The best modification temperature is 750℃,and the best holding time is 15 min.the increase of remelting times will lead to the failure of modification,The remelting times should not exceed three times without affecting the modification effect of rare earth Eu.

关 键 词：铝硅合金 冷却速率 稀土元素 共晶硅 

分 类 号：TG146[一般工业技术—材料科学与工程]