Abstract

The results of an end-to-end quality evaluation of continuous cast SS400 steel slabs, followed by its hot-rolled thick-sheet products in ship-delivered batches, are presented. The evaluation of the frequency distribution of defects for each of the continuous casting machines (CCMs) revealed the following: even during control fire cleaning, the surface quality of slabs from CCM No. 1 was slightly lower (1.1–2.0%) than from CCM No. 2; the finished sheets from slabs casted at CCM No. 1 have a better quality than from slabs casted at CCM No. 2. At the same time, on both machines, the quality of slabs from strand No. 2 is better than from strand No. 1. The unstable internal quality of the sheet with a thickness of 30–45 mm was due to restrictions imposed on the maximum thickness of the sheet which was 25.0 mm. During microstructural analysis of the causes of cracks and segregation nature, it was found that the presence of non-metallic inclusions in the sheet structure serves, in fact, as a source of crack development. Analysis using energy-dispersive x-ray spectroscopy (EDX) showed that nonmetallic inclusions in the dominant mass are manganese sulfides.

中文翻译：

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船运批量连续铸坯和热轧薄板产品的端到端质量评估

摘要

介绍了对SS400连铸坯进行端到端质量评估的结果，然后介绍了船运批量生产的热轧厚板产品。对每台连续铸造机（CCM）的缺陷频率分布进行评估后发现：即使在控制火清理期间，CCM No. 1的板坯表面质量也比CCM No. 1的板坯表面质量略低（1.1–2.0％） 2号 用1号CCM浇铸的板坯的成品质量要比2号CCM浇铸的板坯的质量更好。同时，在两台机器上，2号钢坯的板坯质量都比2号钢坯的板坯质量好。 1.厚度为30-45毫米的板材的内部质量不稳定是由于对板材的最大厚度25.0毫米施加了限制。在对裂纹原因和偏析性质进行微观结构分析时，发现板材结构中非金属夹杂物的存在实际上是裂纹发展的根源。使用能量色散X射线光谱法（EDX）进行的分析表明，主要成分中的非金属夹杂物是硫化锰。