纳米TiO2对离心自蔓延复合钢管组织性能的影响

摘要

In order to improve the density and mechanical properties of ceramic lined composite steel pipes produced by Centrifugal Self propagating High temperature Synthesis,composite steel pipes are prepared by centrifugal SHS method on the basic of Al Fe2 O3 sys-tem.With the condition of adding 6 % SiO2 and 4 % Na2 B4 O7 ,the effect of different amount of nano TiO2 on the microstructure and the mechanical properties of composite steel pipes are studied.By means of SEM analysis,XRD and mechanical tests,the results show that the ceramic layer consists of main crystal phase ofα Al2 O3 ,with small amount phases of FeAl2 O4 ,Al2 SiO5 and B2 O3 .The surface of ceramic layer is smooth,no obvious crack and with good density.The shearing strength of the ceramic layer and the crushing strength of the compos-ite pipe are 13.5 MPa under 8 % (in mass)nano TiO2 and 525 MPa.The density of ceramic layer is up to 94.2 %.%为了提高离心 SHS复合钢管的致密度及力学性能,针对Al Fe2 O3铝热体系,在铝热剂中添加质量分数6%SiO2、4%Na2 B4 O7,采用离心自蔓延高温合成法制备出陶瓷内衬复合钢管,研究不同质量分数的纳米 TiO2添加剂对复合钢管组织结构及力学性能的影响。XRD分析表明,陶瓷层的主要成分为α Al2 O3,还有少量 Al2 SiO5,B2 O3存在。SEM观察发现陶瓷层表面无裂纹、致密度良好。力学实验结果表明,加入8%(质量分数)纳米TiO2的陶瓷层的压剪强度及复合钢管的压溃强度分别达到13.5 MPa和525 Mpa,测试结果表明致密度可达94.2%。