The addition of Ni element into steel to prolong the service life of coated steel was investigated in marine atmospheric environment by laboratory simulated accelerated experiment.The scanning electron microscope and ...The addition of Ni element into steel to prolong the service life of coated steel was investigated in marine atmospheric environment by laboratory simulated accelerated experiment.The scanning electron microscope and electron probe microanalysis combined with electrochemical impedance spectroscopy were used to characterize coated steel properties and examined the anti-corrosion performance.The results showed that 3 wt.%Ni-advanced steel(3Ni steel)substrate obviously delayed the failure time of coating compared to carbon steel,therefore prolonging the service life of coating on the steel.X-ray diffraction patterns for the corrosion products under the scratched coating on 3Ni steel exhibited that FeNi_(2)O_(4) and Fe_(2)O_(3) occurred in the corrosion product of 3Ni steel.It was also found that Ni element enriched in the product layer through analyzing the appearance and composition of corrosion products by electron probe micro-analysis.Chloride ions were blocked out of product by the enrichment of Ni element in rust layer.展开更多
The conventional Al2O3-13 wt. % TiO2 composite ceramic coatings are fabricated by plasma spraying on the surface of extrusion wheel. The microstrueture, morphology and phase compositions of the substrate and coat- ing...The conventional Al2O3-13 wt. % TiO2 composite ceramic coatings are fabricated by plasma spraying on the surface of extrusion wheel. The microstrueture, morphology and phase compositions of the substrate and coat- ing are investigated by using X-ray diffractometry (XRD) , scanning electron microsopy (SEM) and energy dis- persive spectroscopy (EDS). Moreover, the microhardness of the substrate and the coating are investigated using Vickers mierohardness tester, the friction and wear behaviors of the substrate and the coating are investigated by using a block-on-ring tribometer under dry sliding conditions with the load of 245 N. The results show that both γ-Al2O3 and α-Al2O3 phases are observed in the as-sprayed coatings, the mian phase is γ-Al2O3. There are white particulates Al2O3 on its surface. The Al2O3-13 wt. % TiO2 coating possesses higher mierohardness which is about 1018HV and 1.6 times that of the substrate. The wear performance of coating is better than that of the substrate. In a practical application, the life of the extrusion wheel which is plasma sprayed Al2O3-13 wt. % TiO2 coating on the surface is 1.2 times that of the conventional extrusion wheel, and the life is about 330 h.展开更多
基金National Key Research and Development Program of China(2016YFC0401205).
文摘The addition of Ni element into steel to prolong the service life of coated steel was investigated in marine atmospheric environment by laboratory simulated accelerated experiment.The scanning electron microscope and electron probe microanalysis combined with electrochemical impedance spectroscopy were used to characterize coated steel properties and examined the anti-corrosion performance.The results showed that 3 wt.%Ni-advanced steel(3Ni steel)substrate obviously delayed the failure time of coating compared to carbon steel,therefore prolonging the service life of coating on the steel.X-ray diffraction patterns for the corrosion products under the scratched coating on 3Ni steel exhibited that FeNi_(2)O_(4) and Fe_(2)O_(3) occurred in the corrosion product of 3Ni steel.It was also found that Ni element enriched in the product layer through analyzing the appearance and composition of corrosion products by electron probe micro-analysis.Chloride ions were blocked out of product by the enrichment of Ni element in rust layer.
文摘The conventional Al2O3-13 wt. % TiO2 composite ceramic coatings are fabricated by plasma spraying on the surface of extrusion wheel. The microstrueture, morphology and phase compositions of the substrate and coat- ing are investigated by using X-ray diffractometry (XRD) , scanning electron microsopy (SEM) and energy dis- persive spectroscopy (EDS). Moreover, the microhardness of the substrate and the coating are investigated using Vickers mierohardness tester, the friction and wear behaviors of the substrate and the coating are investigated by using a block-on-ring tribometer under dry sliding conditions with the load of 245 N. The results show that both γ-Al2O3 and α-Al2O3 phases are observed in the as-sprayed coatings, the mian phase is γ-Al2O3. There are white particulates Al2O3 on its surface. The Al2O3-13 wt. % TiO2 coating possesses higher mierohardness which is about 1018HV and 1.6 times that of the substrate. The wear performance of coating is better than that of the substrate. In a practical application, the life of the extrusion wheel which is plasma sprayed Al2O3-13 wt. % TiO2 coating on the surface is 1.2 times that of the conventional extrusion wheel, and the life is about 330 h.