CAJ | 학술논문

钩状裂纹缺陷是导致中碳J55钢超声波探伤不合格的主要原因. 针对中碳J55钢HFW焊接过程中出现的不同钩状裂纹缺陷进行了分析, 并提出了改进措施. 研究结果表明, 造成中碳J55钢HFW焊接钩状裂纹的主要原因为钢中的大颗粒夹杂物以及板厚1/4位置严重偏析, 且现有的夹杂物及带状组织检验标准难以对J55钢的质量进行有效管控. 通过减少单中包连浇炉次、增加铸坯头尾切废量以及改用直弧形连铸机等措施, 钩状裂纹缺陷率可大幅降低.
구상렬문결함시도치중탄J55강초성파탐상불합격적주요원인. 침대중탄J55강HFW한접과정중출현적불동구상렬문결함진행료분석, 병제출료개진조시. 연구결과표명, 조성중탄J55강HFW한접구상렬문적주요원인위강중적대과립협잡물이급판후1/4위치엄중편석, 차현유적협잡물급대상조직검험표준난이대J55강적질량진행유효관공. 통과감소단중포련요로차、 증가주배두미절폐량이급개용직호형련주궤등조시, 구상렬문결함솔가대폭강저.
Hook crack is the fundamental reason for the rejection of ultrasonic detection. Different kinds of hook crack defects, which happened during HFW welding of medium-carbon J55 steel, were analyzed, and effective measures were given. The results showed that large inclusions and severe segregation at 1/4 thickness are mine reasons for hook crack defects, and the existing inclusion and banded structure test standards were proved ineffective. By reducing the number of casting furnace, increasing the cutting length of slab head and tail and using straight arc slab casting machine, hook crack defects could be greatly reduced.