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研讨有关浇铸小截面铸坯时钢中夹渣与氧化物夹杂问题和减少其数量的可能性。为了消除连铸结晶器中渣的有害影响和降低铸坯的表面和内部氧化物夹杂的数量,必须采用使熔池内的氧达得额定量以满足连铸的要求的脱氧方法。当脱氧不好和(或)在出钢和浇铸期间,钢水温降很大时,由于二次脱氧反应可能出现渣量增大,钢流和大气氧的相互作用同样可能导致生成新渣。特别困难的是在浇铸小截面铸坯时,防护钢流不受大气氧化,采用液化惰性气防护能获得好的结果。氧在钢中以溶解形式以及与氧有亲和力的元素的化合物形式存在。溶解氧含量表示钢水氧化度。由于脱氧的结果,溶解氧结合成稳定的化合物。此外,脱氧产物必须尽快地从钢水中排出。保留在凝固了的钢中氧化物表明钢的纯净度。残氧量取决于所使用的脱氧剂性能和钢水温度。因而脱氧反应在温度降低时可能继续进行。在冶炼高纯净钢的过程中,必须保证钢水在凝固前避免与渣中氧、耐火材料中氧特别是大气氧的互相作用。连铸时,在结晶器中出现大量渣说明为了提高钢的纯度所采取的措施效果不佳。此外,该渣会使漏钢的频率增大,同时会恶化铸坯表面质量。多数的情况下出现这类情况的原因一般认为熔炼和脱氧工艺遭受破坏,二次脱氧反应如同不佳的脱氧和(或)出钢浇钢期间的温降过大,钢水与大气氧的相互作用是产生该渣的原因。钢中央渣和氧化物夹杂是在浇铸小截面铸坯时出现的主要夹杂,因为强脱氧剂,诸如铝,只是在有限范围内才可以采用,而已知的防护钢流免遭大气氧化方法只可能在有限的范围内采用。本文研讨有关浇铸小截面铸坯时钢中央渣和氧化物夹杂的问题及其减少它们数量的方法
Discuss the possibility of inclusions and oxides inclusions in steel and reduce their number when casting small cross-section billet. In order to eliminate the detrimental effects of slag in the continuous casting mold and reduce the amount of oxide inclusions on the surface and the interior of the strand, it is necessary to use a deoxidation method which allows the oxygen in the melt pool to be rated to meet the requirements of continuous casting. When the deoxidation is not good and / or during the tapping and casting, the temperature of the molten steel is very high, the amount of slag may increase due to the secondary deoxidation reaction, and the interaction between the steel flow and the atmospheric oxygen may also lead to the generation of new slag. Particularly difficult is the protection of the steel stream from atmospheric oxidation during the casting of small sections of the slab, with liquefied inert gas protection giving good results. Oxygen exists in the steel as a compound in dissolved form and as an element with oxygen affinity. Dissolved oxygen content refers to the degree of oxidation of molten steel. As a result of the deoxygenation, dissolved oxygen combines into a stable compound. In addition, deoxidation products must be drained from the molten steel as soon as possible. The oxides retained in the solidified steel indicate the purity of the steel. The amount of residual oxygen depends on the deoxidizer used and the temperature of the molten steel. Therefore, the deoxygenation reaction may continue when the temperature decreases. In the process of smelting high-purity steel, it is necessary to ensure that the molten steel before solidification avoids the interaction with the oxygen in the slag and the oxygen in the refractory, especially the atmospheric oxygen. In continuous casting, large amounts of slag appeared in the crystallizer indicating that the measures taken to increase the purity of the steel did not work well. In addition, the slag will increase the frequency of the steel breakout and deteriorate the surface quality of the slab. In most cases, the reasons for such situations are generally believed that the smelting and deoxidation process is destroyed, the second deoxygenation reaction is as bad as the deoxidation and / or the temperature drop during steel pouring is too large, the interaction between molten steel and atmospheric oxygen Is the cause of the slag. Steel slag and oxide inclusions are the major inclusions in the casting of small cross-sections because strong deoxidizing agents, such as aluminum, are only used to a limited extent and the known method of protecting the steel from atmospheric oxidation is only possible Used within a limited range. This paper discusses the problem of inclusions of steel central slag and oxides and the method of reducing their number when casting small sections of slabs