The plasma sprayed gradated coating with the bottom layer of NiCrAl and the top layer of(ZrO2+Y2O3) was prepared by the plasma spraying technique. The phase structure and morphology of the gradated coating were analyz...The plasma sprayed gradated coating with the bottom layer of NiCrAl and the top layer of(ZrO2+Y2O3) was prepared by the plasma spraying technique. The phase structure and morphology of the gradated coating were analyzed by means of X-ray diffractometry(XRD) and scanning electron microscopy(SEM). The high temperature oxidation resistance of the plasma sprayed samples at 800 ℃ was investigated. The oxidation kinetics curve was obtained. The results show that the thickness of gradated coating is about 410 μm. The plasma sprayed gradated coating on stainless steel surface can improve the high temperature oxidation resistance of stainless steel. The oxidation rate of stainless steel is less than that of plasma sprayed gradated coating. The oxidation film of plasma sprayed sample is very dense and is not easily exfoliated. The dense oxidation film prevents the stainless steel from more oxidation.展开更多
基金Project(20061D0500500151) supported by Beijing Excellent Talent Nurture and Sponsor programProject supported by Academic Human Resources Development in Institutions of Higher Learning under the Jurisdiction of Beijing Municipality
文摘The plasma sprayed gradated coating with the bottom layer of NiCrAl and the top layer of(ZrO2+Y2O3) was prepared by the plasma spraying technique. The phase structure and morphology of the gradated coating were analyzed by means of X-ray diffractometry(XRD) and scanning electron microscopy(SEM). The high temperature oxidation resistance of the plasma sprayed samples at 800 ℃ was investigated. The oxidation kinetics curve was obtained. The results show that the thickness of gradated coating is about 410 μm. The plasma sprayed gradated coating on stainless steel surface can improve the high temperature oxidation resistance of stainless steel. The oxidation rate of stainless steel is less than that of plasma sprayed gradated coating. The oxidation film of plasma sprayed sample is very dense and is not easily exfoliated. The dense oxidation film prevents the stainless steel from more oxidation.
文摘采用溶胶-凝胶法,以异丙醇铝为前驱体制备Al2O3溶胶,浸渍提拉后800℃下真空烧结,在316L奥氏体不锈钢表面制备出无裂纹的Al2O3涂层,研究涂层层数对316L奥氏体不锈钢高温抗氧化性能的影响.通过XRD和DSC对干凝胶粉末进行分析,并使用SEM研究Al2O3涂层表面形貌特征.涂层的高温抗氧化性能则使用氧化称重法来表征,对比有涂层试样和空白试样在高温氧化环境中的增重比.结果表明:制备出的涂层Al2O3颗粒均匀细小,有效阻止了氧化的进程,提拉3次制备的涂层的抗高温氧化效果最佳,在800℃使用的情况下至少延缓氧化时间165 h.
