Na_2B_4O_7添加剂对复合钢管陶瓷衬层组织性能的影响

The Effect of Na 2B 4O 7 Additive on the Structure and Properties of Ceramic Layers of Composite Pipes

采用铝热离心法制备了陶瓷内衬钢管，研究了Ｎａ２Ｂ４Ｏ７ 添加剂和过铝量对陶瓷内衬致密度、组织和性能的影响。在自蔓延过程中作为稀释剂存在的Ｎａ２Ｂ４Ｏ７，降低燃烧温度和燃烧速率。添加剂对陶瓷致密化具有双重影响。５％ ～１０ ｗ ｔ％ 添加剂，延长陶瓷层的熔融期，可明显改善陶瓷致密度和内表面光整度。陶瓷层无裂纹和剥皮现象。陶瓷晶粒呈等轴状。随着添加剂量的增加，陶瓷硬度和耐蚀性均稍有下降。陶瓷内衬钢管具有优异的抗热冲击性能。

The ceramic lined pipes have been produced by SHS-centrifugal process.The effects of Na 2B 4O 7 additive and excess AL on density,structure and properties of ceramic layer are investigated.In SHS process Na 2B 4O 7 as diluent,may decrease combustion temperature and combustion rate.The additive has effects on ceramic densification.The density and inner surface smoothness are improved significantly by expanding the cooling time with 5~10wt% Na 2B 4O 7.No crack is oberserved in ceramic layer.The ceramic grains are of axialite and the ceramic hardness is reduced somewhat with increasing quantity of the additive.The corrosion resistance of ceramic against acid with the additive is lower than that without additive.The ceramic lined pipe has high resistance against therma shock.