碳钢/不锈钢液固浇铸复合界面特性研究  

Interfacial characteristics of combined carbon steel and stainless steel based on casting process

作　　者：张开斌 李根 董延楠 郑震 杨岩 张家泉[1] ZHANG Kaibin;LI Gen;DONG Yannan;ZHENG Zhen;YANG Yan;ZHANG Jiaquan(School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China;Lichen Technology Co.,Ltd.,Qingdao 266431,Shandong,China)

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083 [2]青岛力晨新材料科技有限公司,山东青岛266431

出　　处：《钢铁研究学报》2023年第3期293-302,共10页Journal of Iron and Steel Research

摘　　要：界面特性对于碳钢/不锈钢双金属复合材料的质量控制至关重要。基于碳钢/不锈钢液-固复合新材料与工艺开发需要,对Q235/304液-固浇铸复合工艺进行了凝固模拟分析,并利用浇铸实验与剪切实验研究了液-固复合界面的组织与成分变化行为及其对后续轧材力学性能的影响。研究表明,不锈钢基板结合面凹槽化预处理有助于提高整体浇铸复合效果;实现有效冶金复合的温度与界面重要条件则为较高的碳钢过热钢液与不锈钢基板预热温度。其中,液-固复合工艺实现2钢种界面冶金复合的主要特征是:基板界面侧产生有一定厚度的重熔层;复合界面具有一定厚度的合金元素扩散层。据此,获得的液-固复合界面热轧态剪切强度达400 MPa以上,远高于国标210 MPa的门槛值,有望更好地提高这类双金属复合材料的服役性能。The interfacial characteristics of combined carbon steel and stainless steel play a vital role to the final quality of the bimetal materials. For the development of a kind of new composite based on casting practice, a 3-D solidification simulation was carried out to analyze the casting process of Q235 carbon steel upon 304 steel substrate. Besides, interfacial metallography was observed together with interfacial chemistry analyzed by optical microscope and scanning electron microscope of casting and shear process. Also, the interfacial shear stress of combined casting Q235/304 was measured. The results show that pretreatment of substrate positively affect interfacial quality of combined casting materials. It shows that a higher superheat for carbon steel and the base stainless steel with elevated temperature are the most important factors for an effective combination of the double metals by casting, while the grooved pretreatment to the base steel is essential for much improved interface quality. The characteristics of the metallurgical combined interface can be concluded as that there exists a remelting zone at the interface, which shows a finer solidification microstructure, and there appears an alloy elements diffusion layer at the interface as well. The existence of the interface with metallurgical combination shows that the shear stress exceeds 400 MPa, much higher than 210 MPa as given in GB 6396-2008, which should be beneficial to the final process properties and/or service properties of the bimetal composite.

关 键 词：碳钢/不锈钢 液-固复合 凝固模拟 界面形貌 微观组织 

分 类 号：TF77[冶金工程—钢铁冶金]