中厚板厚度中心处裂纹分析与控制

针对探伤合格率低的问题,对探伤不合钢板进行解剖分析,认为引起探伤不合的原因是钢板厚度中心处存在聚集分布的微裂纹。通过对微裂纹产生主要因素的调查和针对性的对比试验,发现微裂纹的产生除与铸坯偏析、MnS夹杂、道次压下率等有关外,钢中的H含量是一个至关重要的影响因素。通过采取降低钢中H含量的措施,实现了钢中H含量的大幅度降低,探伤合格率由原来的95%提高到98%以上。

Analysis and Controlling of the Cracks in the Thickness Center of Medium Plate

Aiming at the problem of low detection qualification rate, the disqualification plate in flaw detection was analyzed. The cause is the existence of micro crack aggregated distribution in the plate thickness center. Through the investigation of main factors on the micro crack and the contrast test, the results showed that the micro cracks is not only concerned with billet segregation, MnS inclusion, pass reduction rate, but hydrogen content in steel is one of the most important factors. By taking measures to reduce the content of hydrogen in steel, the H content in steel is greatly reduced, the flaw detection qualified rate is increased from 95%to 98%.