摘要
铸造焦含固定碳89%,冶金焦含固定碳84%,两者差5%。而冲天炉熔炼铁水渗碳,前者30%,后者12%,相差一倍多。目前的理论认为,渗碳过程是溶解过程,无法解决上述现象。笔者通过研究,认为渗碳开始是溶解过程,渗碳后残灰覆盖在焦炭表面,碳在灰中扩散困难,当灰层把全部焦炭表面覆盖,渗碳过程终止。灰层成为渗碳的关键。铸造焦的灰分中含K_2O多,熔点低,质轻,与焦炭表面结合力弱,容易脱落、漂浮,渗碳容易。而冶金焦的灰中含Fe_2O_3多,熔点高,质重,与焦炭表面结合力强,灰不易剥落,渗碳困难。本文还进行了热力学与动力学分析与计算。
Carbon content of foundry coke (FC) is 89% and that of metallurgical coke (MC) is 84%. The difference is 5%. But, the carburization late of molten iron for FC is 24%, while that for MC is 12%, only a half of FC. This phenemenon can be explained by present theory which holds that the carburization is a dissolution prccess of caibon. But, after a series of experiments, the authors conclude that, in the beginning, the carburization runs as dissolution, then ash forms and covers coke surface. The carburization stops when all the surface has been covered because of difficult diffusion in the ash layer, which becomes limited step for the carburization. The ash of FC contains a let of K_2O and has low melting temperature, light weight and weak affinity to coke. This characteristics make it easy to peel off and float, so that the carbuization becomes easier. MC has opposite properties. Some thermodynamic and kinetic analyses and calculation have been done as well.
出处
《钢铁》
CAS
CSCD
北大核心
1991年第5期1-5,共5页
Iron and Steel
