工艺参数对压铸Al-Si-Mg合金组织和性能影响  

Effects of Process Parameters on Microstructure and Properties of Die Casting Al-Si-Mg Alloy

作　　者：马超 李志广 徐世文 刘海峰 白帮伟 王巍 李永飞 武国春 张宏仁 Ma Chao;Li Zhiguang;Xu Shiwen;Liu Haifeng;Bai Bangwei;Wang Wei;Li Yongfei;Wu Guochun;Zhang Hongren(CITIC Dicastal Co.,Ltd.)

机构地区：[1]中信戴卡股份有限公司

出　　处：《特种铸造及有色合金》2023年第10期1421-1424,共4页Special Casting & Nonferrous Alloys

摘　　要：研究了浇注温度、压射时间和化学成分对压铸Al-Si-Mg合金显微组织中预结晶组织(ESCs)的数量和形貌以及对铸件本体力学性能的影响。结果表明,显微组织中的ESCs是影响铸件本体性能的重要因素。提升熔体浇注温度可以显著减少显微组织中的ESCs,并促进其形貌由树枝状向球状转变,提升铸件本体的屈服强度和硬度;增加压射等待时间,显微组织中的ESCs的面积分数和平均尺寸呈增大趋势,铸件本体的屈服强度和硬度呈下降趋势;Si含量由7.0%提升至7.5%,可降低液相线温度,显著减少ESCs,提升力学性能。通过调整浇注温度、压射等待时间和铝液化学成分,可以有效地减少ESCs的数量和尺寸,从而明显改善力学性能,特别是屈服强度和硬度。The effects of pouring temperature,injection holding time and chemical composition on the quantity and morphology of externally solidified crystals(ESCs)in the microstructure of die casting Al-Si-Mg alloy and on the mechanical properties of the castings were analyzed.The results indicate that ESCs in the microstructure is an important factor affecting the properties of castings.Increase of the pouring temperature can significantly reduce in the microstructure,promote the transformation of morphology from dendritic to spherical,and improve the yield strength and hardness of the die castings.With the increase of injection holding time,area fraction and average diameter of ESCs in the microstructure are increased,while the yield strength and hardness of the castings are decreased.With content of Si increased from 7.0%to 7.5%,the ESCs can be significantly reduced and the mechanical properties can be improved by reducing the liquidus temperature.By adjusting the pouring temperature,injection holding time and chemical composition of molten aluminum,the quantities and size of ESCs can be effectively reduced,thus obviously improving the mechanical properties,especially yield strength and hardness.

关 键 词：浇注温度 压射等待时间 SI含量 预结晶 力学性能 

分 类 号：TG249.2[金属学及工艺—铸造] TG146.21[一般工业技术—材料科学与工程]