The fabrication of the high speed steel matrix composites reinforced by WC particles utilizing the ultrasonicgas atomization and spray-deposition was studied. The change of microstware and mechanical Properties of the...The fabrication of the high speed steel matrix composites reinforced by WC particles utilizing the ultrasonicgas atomization and spray-deposition was studied. The change of microstware and mechanical Properties of thecomposites added WC Particles were investigated and analyzed as well. As some results, the WC particles exhibit tWomorphologies (spherical and angular) with different content of WC particles; and with the increase of content of WCparticles, the hardness of the composites increases, yet the bending strength appears a trend of decreasing.展开更多
A high speed steel composite roll billet was fabricated, which is regular in shape, smooth in surface, slight in trace, compact in internal structure, free of slag inclusion, shrinkage cavity, cracks and other flaws, ...A high speed steel composite roll billet was fabricated, which is regular in shape, smooth in surface, slight in trace, compact in internal structure, free of slag inclusion, shrinkage cavity, cracks and other flaws, and good in macro quality of junction surface using a vertical continuous casting machine. The interface zone microstructure of bimetallic in billet of high speed steel composite roll was analyzed by metallurgical microscope(OM), X-ray diffractmeter(XRD), scanning electron microscopy(SEM) and energy-dispersive X-ray analysis(EDS). The results indicate that the microstructure of roll billet is composed of chilled solidified layer, dendrite zone, interfacial zone of bimetal and core material zone. The microstructure of outer shell material is composed of martensite + bainite + residual austenite + some small labyrinth-shape, small-short lath-shape, or dollop-shape eutectic carbides. The microstructure of core material is slice-shape pearlite and a little ferrite along boundary of cells. The interface region microstructure of bimetallic composite roll consists of diffusion region, chilled solidified layer and columnar grain region.展开更多
The process of spray forming utilized to fabricate WC particle-reinforced high speed steel composites has been studied. In addition, microstructures and mechanical properties of M2 high speed steel and its composites ...The process of spray forming utilized to fabricate WC particle-reinforced high speed steel composites has been studied. In addition, microstructures and mechanical properties of M2 high speed steel and its composites made by spray forming have been analyzed. The results show that the primary carbides of high speed steel are of two types: MC and MbC. With the increase in flight distance, the morphology of the primary carbides varies from fine fish-bone-like to islandlike and both bending strength and hardness increase. With the increase in volume fraction of WC reinforcement particles,hardness of the composites increases considerably, but bending strength, however, appears to be a decreasing tendency.展开更多
The process of manufacturing high speed steel matrix composites reinforced by WC particles was studied. The changes in microstructures and mechanical properties of composites with WC particles were also investigated. ...The process of manufacturing high speed steel matrix composites reinforced by WC particles was studied. The changes in microstructures and mechanical properties of composites with WC particles were also investigated. The results show that increasing the deposition height can significantly enhance the bending strength and hardness of the alloy, and that the fishbone like carbide ledeburite structure gradually diminishes as the WC particles content increases. It was discovered that the hardness of the composites increases due to the increase of pointlike carbide ledeburite, accompanying the breaking of the fishbone like and the net like carbides. However, the bending strength deteriorates due to excessive WC particles increasing the brittle interfacial phase.展开更多
文摘The fabrication of the high speed steel matrix composites reinforced by WC particles utilizing the ultrasonicgas atomization and spray-deposition was studied. The change of microstware and mechanical Properties of thecomposites added WC Particles were investigated and analyzed as well. As some results, the WC particles exhibit tWomorphologies (spherical and angular) with different content of WC particles; and with the increase of content of WCparticles, the hardness of the composites increases, yet the bending strength appears a trend of decreasing.
基金Project(200809123) supported by the National Natural Science Foundation of China
文摘A high speed steel composite roll billet was fabricated, which is regular in shape, smooth in surface, slight in trace, compact in internal structure, free of slag inclusion, shrinkage cavity, cracks and other flaws, and good in macro quality of junction surface using a vertical continuous casting machine. The interface zone microstructure of bimetallic in billet of high speed steel composite roll was analyzed by metallurgical microscope(OM), X-ray diffractmeter(XRD), scanning electron microscopy(SEM) and energy-dispersive X-ray analysis(EDS). The results indicate that the microstructure of roll billet is composed of chilled solidified layer, dendrite zone, interfacial zone of bimetal and core material zone. The microstructure of outer shell material is composed of martensite + bainite + residual austenite + some small labyrinth-shape, small-short lath-shape, or dollop-shape eutectic carbides. The microstructure of core material is slice-shape pearlite and a little ferrite along boundary of cells. The interface region microstructure of bimetallic composite roll consists of diffusion region, chilled solidified layer and columnar grain region.
文摘The process of spray forming utilized to fabricate WC particle-reinforced high speed steel composites has been studied. In addition, microstructures and mechanical properties of M2 high speed steel and its composites made by spray forming have been analyzed. The results show that the primary carbides of high speed steel are of two types: MC and MbC. With the increase in flight distance, the morphology of the primary carbides varies from fine fish-bone-like to islandlike and both bending strength and hardness increase. With the increase in volume fraction of WC reinforcement particles,hardness of the composites increases considerably, but bending strength, however, appears to be a decreasing tendency.
文摘The process of manufacturing high speed steel matrix composites reinforced by WC particles was studied. The changes in microstructures and mechanical properties of composites with WC particles were also investigated. The results show that increasing the deposition height can significantly enhance the bending strength and hardness of the alloy, and that the fishbone like carbide ledeburite structure gradually diminishes as the WC particles content increases. It was discovered that the hardness of the composites increases due to the increase of pointlike carbide ledeburite, accompanying the breaking of the fishbone like and the net like carbides. However, the bending strength deteriorates due to excessive WC particles increasing the brittle interfacial phase.
