摘要
研究了浇铸温度、冷却速度和保温时间对Al-3Ti-0.2C-5Sr铝合金细化剂显微组织的影响,并通过DSC分析及液淬实验研究了其凝固过程.结果表明：Al-3Ti-0.2C-5Sr铝合金细化剂主要由Ti Al_3相、Al-Ti-Sr相、Ti C颗粒及少量Al_4Sr相组成;随着浇铸温度的降低,合金中Ti Al_3相由长条状逐渐转变为块状,Al-Ti-Sr相由包覆状转变为包覆状和块状共同存在;随着冷却速度的降低,Ti Al_3相尺寸减小,包覆状Al-Ti-Sr相增厚;随着保温时间的延长,Ti Al_3相逐渐消失,包覆状Al-Ti-Sr相转变为大块状;Al-3Ti-0.2C-5Sr细化剂的液固区间为800~640℃,各相析出顺序为：Ti Al_3相、Al-Ti-Sr相、Al_4Sr相、α-Al相.
The influence of casting temperature,holding time and cooling rate on Al-3Ti-0. 2C-5Sr alloy microstructure,and the solidification processes were studied by DSC analysis and liquid quenching experiments.The results show that,Al-3Ti-0. 2C-5Sr grain refiner is composed of Ti Al_3 phase,Al-Ti-Sr phase,Ti C phase and small amounts of Al_4 Sr phase. With the increase of casting temperature,strip Ti Al_3 phases in the alloy gradually transforms into massive,and the coated Al-Ti-Sr phases can change into block Al-Ti-Sr phases.With the decreasing cooling rate,size of Ti Al_3 decreases the coated Al-Ti-Sr phases thickens. With the increase of the holding time,Ti Al_3 phase gradually disappears,and the coated Al-Ti-Sr phases become big block phases. Liquid-solid temperature range of Al-3Ti-0. 2C-5Sr grain refiner is 800 ~ 640 ℃,precipitation sequence of phases is Ti Al_3 phases,Al-Ti-Sr phases,Al_4 Sr phases and α-Al.
出处
《郑州大学学报（工学版）》
CAS
北大核心
2015年第6期14-17,共4页
Journal of Zhengzhou University（Engineering Science）
基金
国家自然科学基金资助项目(51174177)
