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碳素钢连铸坯中的凝固组织及其非金属夹杂物的分布取决于一系列的冶金因素。随着钢水温度的降低,等轴晶组织的体积增大。在等轴晶带与柱状晶带的界面附近,或在两个方向相反的柱状晶带相连接的区段,大型硫化物和氧化物夹杂的数量很大。在弧型连铸机上浇铸的铸坯具有不对称的组织和不对称分布的大型夹杂物。而大型夹杂物是在凝固过程的后期阶段形成的,并且与连铸机的类型关系不大。为了研究夹杂物的成分及其尺寸分布状况,制定了新的试验研究方法。在研究氧化物和硫化物夹杂物的形成中心和长大时,这种方法可得出特别引人注目的结果。瑞典冶金研究院曾经进行了有关连铸方坯、大钢坯和板坯中非金属夹杂分布及成分的情报收集工作。对所有的钢浇铸后的状态进行了研究,而对某些碳素钢还对其轧制后的状态进行了研究。这项工作的目的,首先是研究在立式连铸机和弧型连铸机中央杂物上浮对铸坯截面硫化物和氧化物夹杂分布的影响,也是研究碳素钢和奥氏体不锈钢中央杂物尺寸及成分的分布状况。研究工作是以斯堪得纳维亚冶金工厂所获得的资料为基础的。下面提供的是这项研究工作第一个阶段所获得的一些结果。夹杂物的分布取决于诸如凝固速度(其本身与结晶器的尺寸有关)及连铸机的类型等因素。连铸机的类型有好几种,但是本文只研究其中的两种:即立式连铸机和弧型连铸机。与立式连铸机浇铸的钢坯相反,弧型连铸机浇铸的钢坯其非金属夹杂物的分布不对称。有关资料证明,在弧型连铸机上会混有更大的非金属夹杂物。
The distribution of solidified structures and their non-metallic inclusions in a carbon steel billet depends on a number of metallurgical factors. As the temperature of molten steel decreases, the volume of equiaxed grains increases. In the vicinity of the interface between the equiaxed zone and the columnar zone or in the zone where the two oppositely oriented columnar zones are connected, large amounts of sulfide and oxide inclusions are present. Cast slabs cast on an arc-type caster have asymmetric and asymmetric distribution of large inclusions. Large inclusions are formed during the later stages of the solidification process and have little to do with the type of continuous casting machine. In order to study the composition of inclusions and their size distribution, new experimental methods have been developed. This method yields particularly striking results when studying the formation centers and growing up of oxide and sulfide inclusions. The Swedish Institute of Metallurgy has conducted information gathering on the distribution and composition of non-metallic inclusions in continuous casting billets, blooms and slabs. All steel castings after the state has been studied, but also some of the carbon steel is also the state after rolling. The purpose of this work is to study the influence of the floating of the sundries in the vertical continuous casting machine and the arc continuous casting machine on the distribution of inclusions of sulphides and oxides in the billet. It is also to study the carbon steel and austenitic stainless steel central Debris size and composition of the distribution. The research is based on the information obtained from the Scandinavian metallurgical plant. Below are some of the results obtained during the first phase of this research. The distribution of inclusions depends on factors such as the rate of solidification (itself related to the size of the crystallizer) and the type of caster. There are several types of caster, but only two of them are studied in this article: vertical caster and arc caster. In contrast to billets cast by vertical caster, the distribution of non-metallic inclusions in the billet cast by the arc-type caster is not symmetrical. The data prove that larger non-metallic inclusions will be mixed in the arc-type caster.