基于非铝脱氧工艺的高品质轴承钢关键冶金技术研究  

Key metallurgical technology for high-quality bearing steel production based on the nonaluminum deoxidation process

作　　者：王仲亮 包燕平 顾超 肖微 刘宇 黄永生 WANG Zhong-liang;BAO Yan-ping;GU Chao;XIAO Wei;LIU Yu;HUANG Yong-sheng(State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing,Beijing 100083,China;The Third Steel Plant,Zenith Steel Group Co.,Ltd.,Changzhou 213011,China)

机构地区：[1]北京科技大学钢铁冶金新技术国家重点实验室,北京100083 [2]中天钢铁集团有限公司第三炼钢厂,常州213011

出　　处：《工程科学学报》2022年第9期1607-1619,共13页Chinese Journal of Engineering

基　　金：国家自然科学基金资助项目(52174297)。

摘　　要：我国高品质轴承钢生产技术已取得了长足进步,部分企业的轴承钢质量处于世界先进水平,但质量稳定性与世界领先水平仍存在一定差距.目前,国内外主要采用铝脱氧工艺生产轴承钢,通过铝脱氧和造高碱度渣快速降低钢液中氧含量,高品质轴承钢中全氧质量分数已经可以控制在5×10^(-6)以下,但仍存在大颗粒球状(Ds类)类夹杂物导致疲劳失效的难题,以及超低全氧和钛含量难以稳定控制、小方坯连铸水口堵塞等问题.针对上述问题,本研究提出了非铝脱氧工艺生产轴承钢,即在转炉出钢时加入硅锰合金预脱氧,钢包精炼炉(LF)向渣面加入硅质脱氧剂扩散脱氧,真空循环脱气精炼(RH)真空深脱氧,保证钢液全氧质量分数在8×10^(-6)左右.在保证钢液低铝低钛的同时,利用低碱度渣改变夹杂物类型,控制夹杂物塑性化,从而有效地解决钢液流动性问题.利用超声疲劳试验机对两种工艺轴承钢疲劳寿命进行测定,阐明了不同类型夹杂物对疲劳性能的影响,剖析了不同工艺轴承钢的疲劳断裂机理,研究了引起疲劳裂纹的夹杂物临界尺寸.Bearing steel is subjected to complex alternating stress conditions for a long time which requires excellent service properties such as high hardness,high wear resistance,high elastic limit,and high contact fatigue strength.Therefore,during bearing steel production,it is necessary to strictly control the process and improve the purity of steel to ensure high precision,long service life,and high reliability of bearings.China has made considerable progress in the production technology of high-quality bearing steel,and some enterprises can produce world-class bearing steel.However,the stability of bearing steel still requires improvement.Currently,the aluminum deoxidation process is mainly used to produce bearing steel at home and abroad.Through aluminum deoxidation and the production of high-alkalinity slag,the oxygen content in liquid steel can be rapidly reduced.The total oxygen mass fraction in highquality bearing steel can be controlled below 5×10^(-6).However,fatigue failure caused by occasional Ds-type inclusions still occurs.Concurrently,other problems such as blockage of small billet continuous casting nozzle and difficulty in stable control of ultralow total oxygen and titanium content also occur.To circumvent the aforementioned problems,this study proposed a nonaluminum deoxidation process by adding silicon–manganese alloy for pre-deoxidation during converter tapping,adding silicon deoxidizer to the ladle furnace(LF)slag surface for diffusion deoxidation,and Ruhrstahl-Heraeus(RH)vacuum deep deoxidation to ensure that the total oxygen mass fraction of the molten steel was approximately 8×10^(-6),to produce bearing steel.While ensuring the low aluminum and low titanium contents of liquid steel,low-alkalinity slag is used to change the type of inclusions and control the plasticity of inclusions to effectively solve the problem of liquid steel fluidity.The fatigue life of bearing steels by two kinds of processes was evaluated using the ultrasonic fatigue testing machine,the effects of different types of i

关 键 词：轴承钢 硅锰脱氧 真空深脱氧 夹杂物 超声疲劳 

分 类 号：TF762[冶金工程—钢铁冶金]