1. Qian Shun Technology Center, Beijing Shougang Co., Ltd., Qian'an 064404, Hebei, China; 2. Research Institute of Technology, Shougang Group Co., Ltd., Beijing 100043, China
Abstract：Samples of the titanium rich protective layer were obtained by dissection of a BF hearth with long-term titanium addition for the furnace protection, and the formation process of titanium rich protective layer in the blast furnace was deduced. It was found that Ti(C,N) grains were precipitated from the molten iron initially and then grew up in the slag due to grain boundary migration between grains. Finally, Ti(C,N) grains with slag and iron were consolidated to form a protective layer. Furthermore, the 3D morphology of precipitated phase for Ti(C,N) was also observed by the acid attack method. It was found that the surface of Ti(C,N) grains was relatively flat and had a large number of annular layered structures. Besides, a small amount of Ti(C,N) grains were stacked with the cube form and had the loose internal structure.
2021, Vol. 31 
