【作者】 卓晓军； 杨成威； 王万军； 王新华； 崔京玉； 常开地； 王坤；

【Author】 Zhuo Xiaojun~1 Yang Chengwei~1 Wang Wanjun~1 Wang Xinhua~1 Cui Jingyu~2 Chang Kaidi~2 Wang Kun~2 1.School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing,100083; 2.Technical Research Institute,Shougang Group,Beijing,100041

【机构】 冶金与生态工程学院北京科技大学； 首钢技术研究院首钢集团；

【摘要】 对采用“顶底复吹转炉炼钢-LF 精炼-VD 真空处理-喂硫线增硫”工艺路线,生产汽车用非调质钢铸坯的全过程,特别是对非金属央杂物进行了系统的研究。试验证明采用本研究制定工艺路线,非调质钢[P]含量控制在0．012%以下,T[O]含量控制到0．001%左右。LF 精炼过程钢水[N]含量呈略微增加。而钢水 T[O]含量降低较快, T[O]由0．04%降低至0．002%。钢中夹杂物以纯 MnS 夹杂物为主,有少量的氧化物-MnS 复合夹杂物。经过 VD 真空处理,钢水 T[O]含量由 LF 精炼结束时的0．002%降低至0．0011%,[N]则由 LF 结束时的0．008%降低至0．0048 %。氩气软吹后,钢液的 T[O]增加了0．0002%。经真空处理后以及喂线后,钢水试样中除硫化物之外,已很难发现氧化物类夹杂。浇铸过程中间包钢水试样中非金属夹杂物,绝大多数夹杂物为钢水凝固末期生成的硫化物和氮化物,很难观察到氧化物类夹杂物。连铸坯中观察到的非金属夹杂物绝大部分是纯 MnS 夹杂物,尺寸较大呈浅色不规则形状。铸坯中能观察到一些氧化物夹杂,这些氧化物和 MnS 组成复合的夹杂物,呈深色在 MnS 夹杂物的中心, 其尺寸较小约为2μm,此类夹杂物是由于保护浇铸不善而产生的。此外还能观察到尺寸较小的 TiN-VN 类夹杂物, 为凝固末端生成。更多还原

【Abstract】 The manufacture process and non-metallic inclusions of microalloyed forging steel for Automobile was investigated systematically.Phosphorus content and total content could be control below 0.012% and around 0.001% respectively with this technics.During ladle furnace(LF)refining process,nitrogen content increased a little bit,while total oxygen content decreased rapidly from 0.04% to 0.002%.MnS inclusions were dominant with few oxide inclusions in steel.During vacuum degasser(VD)treatment,total oxygen content deceased from 0.002% to 0.0011%,while nitrogen content decreased from 0.008% to 0.0048% too.After soft blowing,total oxygen content increased 0.0002%.After VD vacuum treatment,no oxide inclusion could find except MnS inclusion.During the casting,there was no oxide to be found. Only MnS and carbide inclusions were found which were expected to be formed at the end of solidification.Most inclusions were pure MnS with irregular shape and large size in the slab.But a few complex inclusion(oxide with MnS)could be found with around 2μm,where oxide was located at the center wrapped by MnS.These oxide in complex inclusion formed because of unperfected protecting casting.Although small TiN-VN inclusions could be found which formed at end of solidification.更多还原