SiC coatings were prepared on the surface of C/C composites by pack cementation and chemical vapor deposition.The structure characteristics of SiC coatings respectively prepared by two methods and the oxidation behavior of C/C composites in static air at 1 200 ℃ were analyzed by X-ray diffraction (XRD),scanning electron microscopy (SEM) and thermal oxidation experiments.The results show that the PC-SiC coating is composed of irregular polygonal particles with high binding strength to the matrix,but the carbon fiber of the matrix will be corroded by Si to different degrees during the reaction.With the increase of Al2O3 additive content,the SiC particles in the coating will be refined,resulting in higher density and antioxidant properties.The CVD-SiC coating is composed of spherical SiC particles with poor crystablline,and the coating has high density.Since the coating is prepared by deposition,there is a clear interface between the coating and the C/C matrix,and the binding strength is poor,and the coating is easy to peel during oxidation.As the deposition time increases,the thickness of the coating increases,and the antioxidant performance increases,but it is weaker than the antioxidant capacity of the PC-SiC coating.

The permanent volume changes of the siliceous fireclay mortar before,during and after drying are studied by experiments.The siliceous fireclay mortar joint accounts for 4% of overall height of coke oven masonry,and the great influence of the volume change on whole oven  proper structure must be paid attention to.With the development of large-scale coke ovens,looking for optimal formulas for siliceous fireclay mortar will be the research direction,which will reduce the uncertainty of volume expansion in the future.

Inclined dust zone is the most easily damaged part in CDQ chamber.The life of the refractories in this part can not reach the design working life,which results in shut down for overhaul and has become an important factor that hinders the development of CDQ chamber.Using high-grade new type refractory silicon carbide products can significantly prolong the life of refractories in vulnerable parts.Through analysis,it is known that although the cost of the new material is higher than the ordinary refractories,the service life of the new material is significantly extended,and during the whole life cycle of the refractories,the overall cost can be reduced.

Rotary slag resistance method is adopted for testing the erosion resistance of dense zircon brick against alkali-free glass solution.The  bricks used in kiln are analyzed.The thickness of samples did not change  obviously before and after the test,and the penetration depth was only 3 mm.

Mullite-silicon carbide wet shotcreting castables were prepared by mullite,silicon carbide,corundum fines,alumina powder,CAC,silica powder and so on.The effects of different silica powder additions on rheology and physical performance of shotcreting castables were investigated.The results show that when the silica powder addition is more than 4%,the wet shotcreting castables are pseudoplastic fluid with smaller yield value and apparent viscosity,and have better rheology to be transported.With silica powder increasing,the castables have compact structure and higher cold modulus of rupture.Besides,the castable with 4% silica powder acquires the highest HMOR,which is not favored by more silica powder addition.

In this paper,we began a study of the substitution of brown corundum dust collection powder to the Al2O3≥85% special grade bauxite in refractory.Firstly,the chemical analysis,the grain size analysis,XRD,SEM and EDS of Z1,Z2 and 85 bauxite were comprehensively compared.Then experiments were done to replace of bauxite with dust Z1 and Z2 in the LMG (alumina-magnesia castable).The results confirmed that there are no big differences in the major chemical composition,main phase,particle size distribution between brown corundum dust collection powder and the Al2O3≥85% special grade bauxite.However,morphology of particles and impurity component have some changes.Also,there is no more difference in physical performance at room temperature between the LMG with brown corundum dust and that with the Al2O3≥85% bauxite.Moreover,the above two samples have the similar properties in thermal shock resistance and resistance to slag corrosion.

Standard products drawing library can be created by using the tool palettes function of the Auto CAD.It can reduce the repetitive work in design for refractory materials,minimize work errors and improve work efficiency.