Fe-Cr-Ti-C composite powder was synthesized by precursor carbonization-composition process using the mixture of ferrotitanium, chromium, iron powder and precursor sucrose as raw material. And then the Fe-Cr-Ti-C coati...Fe-Cr-Ti-C composite powder was synthesized by precursor carbonization-composition process using the mixture of ferrotitanium, chromium, iron powder and precursor sucrose as raw material. And then the Fe-Cr-Ti-C coating was prepared by reactive plasma cladding method. Microstructure of the samples was observed by scanning electron microscope （SEM）, the phases were determined by X-ray diffraction （XRD）, and the wear resistance was evaluated under dry sliding wear test conditions at room temperature. Results indicate that the composite coating consists of primary austenite and dendritic eutectic austenite, chrysanthemum-shaped eutectic （Cr, Fe ） 7 C3 and TiC carbide. TiC presents the gradient distribution and different shapes in the coating, corresponding to equiaxial structure both in fusion zone and central zone, while it presents dendritic structure on the surface, respectively. The wear mass loss is insensitive to load for the coating while it increases rapidly for Q235 steel base metal in this test. The wear mass loss ofQ235 steel is 14 times as that of the composite coating under applied load of 40 kg.展开更多
A new type oxidation resistance in situ Cr7 C3/γ-Fe ceramic composite coating was fabricated on hardened and tempered grade C steel by reactive plasma clad with Fe-Cr-C alloy powders. The oxidation resistance of the...A new type oxidation resistance in situ Cr7 C3/γ-Fe ceramic composite coating was fabricated on hardened and tempered grade C steel by reactive plasma clad with Fe-Cr-C alloy powders. The oxidation resistance of the ceramic composite coating was investigated under the test condition of 900 ℃ and 50 hours. The results indicate that the coating has a rapidly solidified microstructure consisting of blocky primary Cr7 C3 and the inter-blocky Cr7 C3/γ-Fe eutectics and is metallurgically bonded to the hardened and tempered grade C steel substrate. The high temperature oxidation resistance of the coating is up to 1.9 times higher than that of grade C steel. The oxidation kinetics curve of the coating is conforming to the parabolic-rate law equation. The excellent oxidation resistance of the coating is mainly attributed to the continuous oxide films which consist of Cr203 and Fe203. The continuous oxide films can prevent the inner part of the coating from being further oxidized.展开更多
基金Supported by Natural Science Foundation of Shandong Province （No. ZR2011EMM017 ）.
文摘Fe-Cr-Ti-C composite powder was synthesized by precursor carbonization-composition process using the mixture of ferrotitanium, chromium, iron powder and precursor sucrose as raw material. And then the Fe-Cr-Ti-C coating was prepared by reactive plasma cladding method. Microstructure of the samples was observed by scanning electron microscope （SEM）, the phases were determined by X-ray diffraction （XRD）, and the wear resistance was evaluated under dry sliding wear test conditions at room temperature. Results indicate that the composite coating consists of primary austenite and dendritic eutectic austenite, chrysanthemum-shaped eutectic （Cr, Fe ） 7 C3 and TiC carbide. TiC presents the gradient distribution and different shapes in the coating, corresponding to equiaxial structure both in fusion zone and central zone, while it presents dendritic structure on the surface, respectively. The wear mass loss is insensitive to load for the coating while it increases rapidly for Q235 steel base metal in this test. The wear mass loss ofQ235 steel is 14 times as that of the composite coating under applied load of 40 kg.
文摘A new type oxidation resistance in situ Cr7 C3/γ-Fe ceramic composite coating was fabricated on hardened and tempered grade C steel by reactive plasma clad with Fe-Cr-C alloy powders. The oxidation resistance of the ceramic composite coating was investigated under the test condition of 900 ℃ and 50 hours. The results indicate that the coating has a rapidly solidified microstructure consisting of blocky primary Cr7 C3 and the inter-blocky Cr7 C3/γ-Fe eutectics and is metallurgically bonded to the hardened and tempered grade C steel substrate. The high temperature oxidation resistance of the coating is up to 1.9 times higher than that of grade C steel. The oxidation kinetics curve of the coating is conforming to the parabolic-rate law equation. The excellent oxidation resistance of the coating is mainly attributed to the continuous oxide films which consist of Cr203 and Fe203. The continuous oxide films can prevent the inner part of the coating from being further oxidized.
