高级别船板钢质量控制的研究

Study on quality control of high grade hull structure steel

为了满足E级船板钢铸坯质量的要求，湘钢采用铁水预处理和钢包精炼技术进行脱氧、脱硫，以及喂钙线到钢包内进行夹杂物变性的方法，改善钢水纯净度，以提高船板钢的韧性。研究发现E级船板钢中，ω（S）低于0．005％，ω（Al）控制在0．03％～0．04％范围，钙铝比控制在0．1左右，可以满足夹杂物变性要求。生产结果表明：低硫、低氧含量控制和钙处理工艺保证了钢水洁净度，提高了湘钢E级船板钢的铸坯质量，解决了其韧性不足的问题。

In order to satisfy the requirements of E-grade hull plate for high quality slab a series of technical measures such as deep desulphurization by hot metal pretreatment, deoxidation and desulphurization by ladle refining and modification of inclusions by feeding Ca-clad wire into the ladle furnace have been taken to improve the cleanliness of the hot metal and raise toughness of the high grade hull plate. It＇s found out in the experiments that the toughness of the E-grade steel can be raised prominently providing that ω（S） is controlled within the limit of less than 0. 005% and the modification of inclusions can be accomplished so long as ω（Al） is defined in the range of 0.03% to 0.04% and ratio of m（Ca）/m（Al） is controlled in about 0. 1. Production results show that by way of control of sulphur and oxygen contents in a very low level and adoption of Ca treatment process the cleanliness of the hot metal and the quality of the E-grade hull plate can be ensured as the strength and toughness of the steel are raised.