利用超高温差热分析和玻璃包熔真空悬浮熔炼技术 ,研究脱氧纯铁及低碳钢中洁净度与过冷度之间的关系。在 2 0 K/ m in冷却速度下 ,纯铁和低碳钢的过冷度为 5 4.4K和 34 .2 K。钢中氧化物含量增加导致过冷度下降 ,氧化物种类对过冷度影响次序为 :Mn O>Si O2 >Mg O>Al2 O3 。在约 2 0 0 0 K/ min冷却速度下 ,低碳钢经玻璃包熔处理后 ,过冷度大幅度提高 ,包熔四次后达到的最大值为 32 8K The relationship between cleanliness and degree of undercooling in deoxidized pure iron and low carbon steel was studied by using ultra-high temperature differential thermal analysis and glass-melting vacuum suspension smelting technology. At 20 K / m in cooling rate, the undercooling of pure iron and mild steel is 5 4.4K and 34.2K. The increase of the oxide content in the steel led to the decrease of undercooling, and the influence order of the oxide types on the supercooling degree is Mn O> Si O2> Mg O> Al 2 O 3. At a cooling rate of about 200 K / min, the degree of subcooling of mild steel increased greatly after the glass was melted. The maximum value reached after the fourth fusion was 32 8K