Acicular ferrite microstructure was achieved for an ultralow carbon pipeline steel through the improved thermome chanical control process (TMCP), which was based on the transformation process of deformed austenite of ...Acicular ferrite microstructure was achieved for an ultralow carbon pipeline steel through the improved thermome chanical control process (TMCP), which was based on the transformation process of deformed austenite of steel. Compared with commercial pipeline steels, the experimental ultralow carbon pipeline steel possessed the satisfied strength and toughness behaviors under the current improved TMCP, although it contained only approximately 0.025% C, vvhich should mainly be attributed to the microstructural characteristics of acicular ferrite.展开更多
The microstructure and properties of high carbonic-chromium cast steel subjected to different hot deformation ratios were studied.The experimental results show that the microstructure and properties of high carbonic-c...The microstructure and properties of high carbonic-chromium cast steel subjected to different hot deformation ratios were studied.The experimental results show that the microstructure and properties of high carbonic-chromium cast steel are obviously improved after hot deformation,and the best mechanical properties of the cast steel can be obtained under hot deformation ratio of 40 %-50 %,which leads to the morphology change of eutectic carbide and the precipitation of granular carbides.展开更多
Metallurgically bonded ceramic coatings were prepared on a steel surface with a combined method of arc spraying and micro-arc oxidation for the first time. Coatings were investigated by X-ray diffraction (XRD) and sca...Metallurgically bonded ceramic coatings were prepared on a steel surface with a combined method of arc spraying and micro-arc oxidation for the first time. Coatings were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Point and line distribution of elements of the ceramic coatings were determined using energy dispersive spectroscopy (EDS). Coatings abrasive wear resistance, corrosion resistance and hot impact property were assessed respectively. The property test results show that metallurgically bonded ceramic coatings were formed on aluminum coatings and the ceramic coatings is mainly composed of a-Al2O3, y-A!2O3^ #-Al2O3 and a little amorphous. The coatings possess excellent abrasive wear, corrosion and hot shock resistance, which can in part be attributed to the gradual distribution of different phases from surface to the substrate.展开更多
Direct reaction synthesis (DRS), based on the principle of self-propagating high-temperature synthesis (SHS), is a new method for preparing participate metal matrix composites. TiCP/AI-4.5Cu-0.8Mg composites were fabr...Direct reaction synthesis (DRS), based on the principle of self-propagating high-temperature synthesis (SHS), is a new method for preparing participate metal matrix composites. TiCP/AI-4.5Cu-0.8Mg composites were fabricated by DRS. Participate composites were fabricated with Ti carbide (TiC) particles, generally less than 1.0μm. The reacted, thermal extruded samples exhibit a homogeneous distribution of fine TiC particles in AI-4.5Cu-0.8Mg matrix. Mechanical property evaluation of the composites has revealed a very high tensile strength relative to the matrix alloy. Fractographic analysis indicates ductile failure.展开更多
基金The present work was financially supported by a China National‘973’Project No.G1998061511the Natural Science Fund of Hebei Province No.501205.
文摘Acicular ferrite microstructure was achieved for an ultralow carbon pipeline steel through the improved thermome chanical control process (TMCP), which was based on the transformation process of deformed austenite of steel. Compared with commercial pipeline steels, the experimental ultralow carbon pipeline steel possessed the satisfied strength and toughness behaviors under the current improved TMCP, although it contained only approximately 0.025% C, vvhich should mainly be attributed to the microstructural characteristics of acicular ferrite.
基金Item Sponsored by Guiding Program of Science and Technology Research of Hebei Province of China(94122123)
文摘The microstructure and properties of high carbonic-chromium cast steel subjected to different hot deformation ratios were studied.The experimental results show that the microstructure and properties of high carbonic-chromium cast steel are obviously improved after hot deformation,and the best mechanical properties of the cast steel can be obtained under hot deformation ratio of 40 %-50 %,which leads to the morphology change of eutectic carbide and the precipitation of granular carbides.
文摘Metallurgically bonded ceramic coatings were prepared on a steel surface with a combined method of arc spraying and micro-arc oxidation for the first time. Coatings were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Point and line distribution of elements of the ceramic coatings were determined using energy dispersive spectroscopy (EDS). Coatings abrasive wear resistance, corrosion resistance and hot impact property were assessed respectively. The property test results show that metallurgically bonded ceramic coatings were formed on aluminum coatings and the ceramic coatings is mainly composed of a-Al2O3, y-A!2O3^ #-Al2O3 and a little amorphous. The coatings possess excellent abrasive wear, corrosion and hot shock resistance, which can in part be attributed to the gradual distribution of different phases from surface to the substrate.
文摘Direct reaction synthesis (DRS), based on the principle of self-propagating high-temperature synthesis (SHS), is a new method for preparing participate metal matrix composites. TiCP/AI-4.5Cu-0.8Mg composites were fabricated by DRS. Participate composites were fabricated with Ti carbide (TiC) particles, generally less than 1.0μm. The reacted, thermal extruded samples exhibit a homogeneous distribution of fine TiC particles in AI-4.5Cu-0.8Mg matrix. Mechanical property evaluation of the composites has revealed a very high tensile strength relative to the matrix alloy. Fractographic analysis indicates ductile failure.
