Abstract:

Two silicon nitride bonded silicon carbide refractories with high silicon nitride content were prepared using high purity silicon carbide and silicon (the silicon addition of samples S1 and S2 is 25 mass% and 35 mass%,respectively) as raw materials,resin as the binder,and firing at 1 400 ℃ for 5 h in a nitrogen atmosphere.For comparison with commercial silicon nitride bonded silicon carbide sample S0 (added with 15 mass% of silicon),the phase composition,the modulus of rupture,the gas permeability,the abrasion resistance and the microstructure of the three samples were studied.The results show that samples S0,S1 and S2 all have excellent modulus of rupture and abrasion resistance.The sharpness of S0 is the strongest,followed by samples S1 and S2.Three samples have the same sequence in terms of the abrasion to the workpiece.Therefore,sample S2 is the most beneficial to the long term service of the workpiece.

Key words: silicon nitride bonded silicon carbide, silicon, abrasion resistance, sharpness

摘要：

以高纯碳化硅、单质硅为原料,树脂为结合剂,在氮气气氛1 400 ℃下保温5 h制备出2种高氮化硅含量的氮化硅结合碳化硅耐火材料(试样S1和试样S2的单质硅添加质量分数分别为25%、35%)。与市售氮化硅结合碳化硅耐火制品S0(单质硅添加质量分数为15%)对比,研究了3种材料的物相组成、抗折强度、透气性、耐磨性、显微结构等。结果表明:3种试样均具有优异的抗折强度及耐磨性,其中试样S0的锋利性最强,试样S1的次之,试样S2的锋利性最弱。就材料的锋利性而言,试样S0对工件的磨损性最大,试样S1次之,试样S2最小。因此,试样S2对工件的长期服役最有利。

关键词: 氮化硅结合碳化硅, 单质硅, 耐磨性, 锋利性