L290M低温韧性不合格的原因分析与改进

Cause Analysis and Improvement of Low Temperature Toughness Incompatibility of L290M

利用扫描电镜和能谱分析等检测手段分析L290M冲击纤维断面率偏低的原因,结果表明,w(S)过高(0.004%),在组织中产生Mn S夹杂物,导致带钢韧性恶化。通过将w(S)控制在0.002%以下,可改善材料塑性,结果显示,-10℃时L290M冲击功纤维断面率趋于稳定,均达到90%以上,性能合格率达到100%。

The reasons for the low cross-sectional area of L290M impact fibers were analyzed using scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS).The results showed that high w(S)(0.004%)resulted in the formation of MnS inclusions in the microstructure,leading to a deterioration in the toughness of the strip steel.By controlling w(S)below 0.002%,material shaping can be improved.The results show that at-10℃,the cross-sectional area of L290M impact energy fibers tends to stabilize,reaching over 90%,and the performance qualification rate reaches 100%.