采用TMCP工艺对高强度船体结构钢EH50的研究与开发

Study and Development of High Strength Structural Steel Applied to Ship EH50 by TMCP Technology

采用TMCP工艺,在实验室对含硼钢和不含硼钢的显微组织和力学性能的变化规律进行了研究。实验结果表明:采用相同的冷却条件,含硼钢的强度明显高于不含硼钢,但伸长率和冲击功低于不含硼钢,且冲击功很不稳定;对于高强度船体结构钢EH50,采用含硼钢,强度和伸长率能达到船级社要求,但冲击功容易出现不合,不含硼钢的强度和韧性能很好地匹配,相对含硼钢具有较低的韧脆性转变温度,建议大生产条件下,采用不含硼钢生产高强度船体结构钢EH50。

By adopting TMCP technique, the microstructure and mechanical properties of boron-added steel and boron-free steel were studied. Experimental result shows that the strength of boron-added steel is noticeably higher than that of boron-free steel, while the elongation and impact energy are lower, and the impact energy is unstable when they are at the same cooling conditions. For high-strength ship structural steel EH50, the strength and elongation can meet the demand of Shipping Bureau with boron-added steel, but the impact energy is unsuitable. On the other hand, the strength and toughness of boron-free steel can well match; boron-free steel has lower ductile-brittle transition temperature. It is suggested that in mass production boron-free steel should be used to produce highstrength ship structural steel EH50.