机构地区: 华南理工大学材料科学与工程学院
出 处: 《材料研究学报》 2011年第4期391-398,共8页
摘 要: 采用超音速火焰喷涂技术在45#钢基体表面制备纳米Ni60-TiB_2复合涂层,研究了纳米和常规微米Ni60-TiB_2复合涂层在静态大气环境下600℃的循环氧化行为。结果表明:纳米Ni60-TiB_2涂层具有晶粒纳米化和微观组织均匀化的特点,其氧化膜由完整连续SiO_2膜构成,在其上均匀地分布着细小的TiO_2颗粒和B_2O_3膜。纳米涂层和微米涂层的循环氧化都为扩散控制机制,但是在纳米涂层表面生成了连续致密的SiO_2膜。晶粒纳米化降低了涂层内应力,提高了膜基结合力,保证了氧化膜的完整性,因此使Ni60-TiB_2复合涂层具有更优的抗氧化性能。 Cycle oxidation resistance of a nanostructured Ni60-TiB2 composite coating sprayed by high velocity oxy-fuel(HVOF) at 600℃in static air was investigated.The conventional Ni60-TiB2 composite coating was also investigated for comparison.The results show that oxide scale on the nanostructured Ni60-TiB2 composite coating consist of complete and continuous SiO2 scale,the fine uniform dispersed TiO2 particles and B2O3 scale spread on the serface of oxide scale.The oxidation process of the nanostructured and conventional Ni60-TiB2 composite coatings are controlled by a diffusion mechanism, and the nanostructured Ni60—TiB2 composite coating exhibits better cycle oxidation resistance than that of the conventional composite coating.The reasons can be attributed to the formation of the intact SiO2 protective layer,and the enhanced adhesion between oxide film and nanocrystalline coating.
领 域: [一般工业技术]