【作者】 刘鹏举；

【导师】 田守信； 赵斌元；

【作者基本信息】 上海交通大学 ， 材料学， 2009， 硕士

【摘要】 双辊薄带连铸工艺以其低能耗、短流程、高速度、低成本的特点顺应了当今钢铁行业发展的趋势,受到世界钢铁企业的广泛关注。钢铁界的专家一致认为双辊薄带连铸技术的工业化应用将会给钢铁生产带来革命性的变革,对钢铁材料生产具有划时代意义。目前,该技术的开发过程中出现产品质量差和工艺不稳定现象,这极大地制约了该技术的产业化。侧封材料就是导致这种现象出现的影响因素之一。为此,本文在宝钢研究院和上海交大材料学院支持下针对新型侧封材料的成分和制备工艺进行了实验研究和理论研究。本文使用2031.3000.010压力测试系统和FV-700型维氏硬度计对材料进行了力学性能测试;使用LFA427激光导热仪、在STA449C/6/GJupiter热分析仪和Dil402e/7/FSO热膨胀测定仪测定了材料的热学性能;在箱式电阻炉和热震炉中测试材料的热稳定性和抗氧化性;用SEM,XRD等手段得到材料物相成分和微观结构。通过对试验结果分析得到以下结论:ZBS系列材料中,BN的含量增加时材料的致密度降低,力学性能变差而热稳定性提高。在BN含量为40%时材料的综合性能达到最佳。ZBS系列材料的力学性能,抗氧化性均随着原料中Si的加入量呈先升高后后降低的趋势。在材料原料中的Si含量为3wt%时材料的总体性能最好。分析认为这是由于加入适量的Si反应后得到SiC对材料起增强作用还可以在材料氧化过程中在材料表面形成氧化膜有效的减缓了材料的氧化。同时Si的加入使得材料的致密度下降,显气孔率升高,使其力学性能和抗氧化性均变差。在Si含量在7wt%到11wt%时这种负作用最明显。ZBT系列材料在烧结过程中有Ti(C、N)生成。材料的微观组织呈疏松的花样叠片状。材料原料中Ti含量增加后材料的致密度降低而力学性能变差。ZBT材料的抗氧化性差在15000C氧化一小时即完全变形。相对于ZBT,ZBC系列材料ZBS系列材料的综合性能最好。ZBS系列材料中ZBS3的热膨胀系数和导热系数可以分别达到3.7×10-60C-1和5.3W/(m*K),两项指标均优于国外热压烧结工艺制备的侧封材料。更多还原

【Abstract】 Twin-roll continuous strip casting process has received many attentions from the steel producers all of the world for its low energy consumption、short procedure、high speed and low production cost which conformed to the developing trend.The experts of steel industry have all recognized that the commercial application of the twin-roll continuous strip casting process will lead to a revolution to steelmaking and become a landmark event for this field. However, the poor quality of casting strip and process stability happened in the research hindered its industrial application. The side dam materials become one of the main defect. Accordingly, this paper dealed with the experimental and theoretical investigations on composition design and production process of new side dam materials with the support of SJTU and BAOSTEEL.The mechanical properties of the side dam material is tested by 2031.3000.010 stress test system and FV-700Vicker’s hardness tester;the thermal properties are tested by LFA427 Laser conductometer、STA449C/6/GJupiter thermal analyzer and Dil402e/7/FSO RPY;The thermal stability and inoxidizability are tested in chamber electric oven and thermal shock oven.; the phases and microstructures are tested by XRD and SEM.In ZBS materials , increasing the content of BN will decrease the density ,worsen the mechanical properties and improve the thermal stability that the optimum combination properties are abtained when the BN content is 40% .The ZBS Materials exhibit a trend that with the increase of BNwt% ,the mechanical property and inoxidizability increase first then decrease ,which showing the best combination property on the point of 3wt%BN. The analyses indicate that adding a proper amount of Si to the raw materials can get SiC in sintering process, which can strengthen the matrix and form compact oxide film on the surface after oxidation reaction. The film hinders the oxidation of the ZBS material effectively. However, the Si will decease the density of ZBS and increase the apparent porosity,which result a poor mechanical property and inoxidizability. The Ill effects are most significant when the Siwt% is between 7% and 11%.T(iC、N)is attained in sintering process of ZBT. The microstructure displays a shape of porous petals. With the increasing of Ti in raw material,the density and mechanical property decrease sharply. The inoxidizability of ZBT is so poor that the material lose its shape after oxidation for 1h at 15000C.Compared with ZBC and ZBT ,the ZBS materials have the best combination properties.The thermal expansion coefficient and thermal conductivity of ZBS3 reach 3.7×10-6 0C-1and 5.3W/(m*K)respectively which is superior to those of other side dam materials produced by hot press process in other countries.更多还原