In this paper, titanium compounds samples were obtained by dissecting the blast furnace for which protected the hearth by adding titanium ores for a long time, and the formation process of the titanium protective layer in the blast furnace was deduced. It was found that Ti(C, N) precipitated in the molten iron initially, and then grew up in the slag by grain boundary migration between grains. Finally, Ti(C, N) grains consolidated with slag and iron to form a protective layer. Furthermore, the 3D morphology of the precipitated phase of Ti(C, N) was also observed by the acid attack method, found that the Ti(C, N) grains mainly in the form of the layered structure and stepped rectangular structure. Besides, the internal of the Ti(C, N) grains was not dense packing. The above results can provide an in-depth understanding of furnace protection with titanium ores.

本文通过长时间加入钛矿石对高炉床进行了解剖，得到了钛化合物样品，推导了高炉中钛保护层的形成过程。发现Ti（C，N）最初在铁水中沉淀，然后通过晶粒间的晶界迁移在炉渣中长大。最后，Ti（C，N）晶粒与炉渣和铁固结形成保护层。此外，还通过酸侵蚀法观察到了Ti（C，N）析出相的3D形态，发现Ti（C，N）晶粒主要为层状结构和阶梯状矩形结构。此外，Ti（C，N）晶粒的内部不致密堆积。