镁质中间包涂料中六偏磷酸钠加入量对IF钢夹杂的影响

Influence of sodium hexametaphosphate addition to magnesia tundish coating on inclusion of IF steel

以电熔镁砂和六偏磷酸钠为原料,按六偏磷酸钠加入质量分数分别为1%、2%、3%、5%配制镁质中间包涂料,浇注成坩埚试样,加入IF钢样,在真空碳管炉中于1 600℃保温120 min进行熔炼试验。对试验后坩埚及IF钢样进行SEM和EDS分析,并检测试验后钢样中总氧含量及夹杂物元素的含量。结果表明:IF钢中O、C、P含量随着镁质中间包涂料中六偏磷酸钠加入量的增加而增多,而Mn、Si、Al、Ti则随着镁质中间包涂料中六偏磷酸钠加入量的增加变化不大。IF钢中的氧化物夹杂以P2O5和MnO为主。

Abstract. Magnesia tundish coatings were prepared using fused magnesia and sodium hexametaphos- phate as starting materials with sodium hexametaphosphate mass percent of 1%,2%,3%, and 5%, re- spectively. The prepared magnesia tundish coatings were cast into crucibles. Then the crucibles added with IF steel were put into a vacuum carbon tube furnace at 1 600 ℃ for 2 h for smelting test. The crucibles and IF steel samples were studied by SEM and EDS. The total oxygen content and inclusion element con- tent of the steel samples were tested. The results show that：with the increase of sodium hexametaphos- phate addition in the magnesia coatings,the contents of O,C,and P in the iF steel increase gradually,and contents of Mn,Si,AI,and Ti in the IF steel change slightly;oxide inclusions in IF steel are mainly P2O5 andMnO.