摘要
采用低熔点Pb_(18)Sn_(12)In_(21)Bi_(49)(质量分数)合金,在不锈钢的锭模中进行浇铸过程底吹氩试验。利用热电偶测定模内不同位置的温度,并采用扫描电镜(SEM)对凝固试样进行铸态相组织观察,研究了浇铸过程底吹氩对合金液温度与合金凝固相组织的影响。试验结果表明,浇铸过程无底吹时,水平方向中心测温点的温度下降很缓慢,浇铸结束后该点的温度骤降到凝固等温平台温度。当浇铸过程底吹氩时,中心点温度以较快的温降速率降低到凝固温度。无底吹氩时,在竖直方向,合金液从下自上依次开始凝固,而底吹氩时,各监测点几乎同时开始凝固。在相同的冷却条件下,浇铸过程底吹氩显著延迟模型下部的开始凝固时间。无底吹氩时检测截面上富Sn相平均直径在2.58μm,当进行底吹氩时,可以有效改善凝固相组织粒径分布,细化合金铸态相组织,截面上富Sn相平均直径约为1.89~2.20μm,较无底吹时降低了26.7%~14.7%。
The low melting point Pb_(18)Sn_(12)In_(21)Bi_(49) alloy(mass fraction)in a stainless steel ingot mold during casting with bottom argon blowing was used to investigate the effects of bottom argon blowing on the temperature of the molten alloy and the microstructure of the solidified phase during casting by measuring the temperature at different positions in the mold by thermocouples and observing the microstructure of the solidified phase by scanning electron microscope(SEM).The experimental results showed that the temperature of the central temperature measurement point in the horizontal direction decreased slowly in the casting process without bottom blowing,and the temperature dropped sharply to the isothermal platform temperature after casting.The central point temperature decreased to solidification at a faster drop rate in the casting process with bottom argon blowing.When there was no bottom blowing argon during casting,the liquid alloy was solidified from bottom to top in the vertical direction,while with the bottom argon blowing,the solidification began at all monitoring points almost simultaneously.Under the same cooling conditions,bottom argon blowing noteworthy delayed the solidification start time at the lower part of the model during the casting process.The average diameter of the Sn-rich phase on the detection cross-section was 2.58μm without bottom argon blowing.In contrast,with bottom argon blowing,the particle size distribution of solidified phase can be effectively improved,the microstructure of as-cast alloy can be refined,and the average diameter of the Sn-rich phase on the crosssection was about 1.89~2.20μm,which was reduced by 26.7%~14.7%compared with that without bottom blowing.
作者
耿云飞
钟良才
杨晓猛
杨仕存
张岭
贺龙龙
Gen Yunfei;Zhong Liangcai;Yang Xiaomeng;Yang Shicun;Zhang Ling;He Longlong(Key Laboratory of Ecological Metallurgy of Polymetallic Ore of Ministry of Education,School of Metallurgy,Northeastern University,Shenyang 110004,Liaoning,China)
出处
《钢铁钒钛》
CAS
北大核心
2022年第2期133-139,共7页
Iron Steel Vanadium Titanium
基金
中央高校基本科研业务专项资金资助(N2125018)
科技部国家重点研发计划资助项目(2017YFB0304100)
国家自然科学基金项目(51574069)。
关键词
模铸
底吹氩
低熔点合金
温度
凝固相组织
mold casting
bottom argon bubbling
low melting point alloys
temperature
solidification phase microstructure
