A theoretical model has been established for calculating the infiltration pressure of metal melt into the preform of ceramic fibers according to the basic principle of hydromechanics. There are three forces acting on ...A theoretical model has been established for calculating the infiltration pressure of metal melt into the preform of ceramic fibers according to the basic principle of hydromechanics. There are three forces acting on the infiltration process in the model, i.e. viscous friction, capillary force, and gravity. The effects of the volume fraction of fibers (V-f) and infiltrating depth on the infiltration pressure are discussed. the results show that the infiltration pressure increases with tile increase of fiber volume fraction and infiltration depth. There is a linear relationship between infiltration pressure and infiltration depth. The effect of gravity on the infiltration pressure can be ignored.展开更多
Influence of Ti on MC carbide of M2 high speed steel was investigated by experimental observation, thermodynamic calculation and crystallographic calculation. With addition of Ti into M2 steel, large quantities of dis...Influence of Ti on MC carbide of M2 high speed steel was investigated by experimental observation, thermodynamic calculation and crystallographic calculation. With addition of Ti into M2 steel, large quantities of dispersed TiC particles formed in the steel melt at higher temperature than that of the formation of MC carbide. TiC can act as heterogeneous nuclei for the crystallization of MC carbide particles, and therefore promote the formation of blocky MC carbide.展开更多
The effect of boron-on carbide morphology of high Cr ledeburite steel has been studied. The results showed that B had obvious influence on eutectic carbide morphology in solidification structure and carbide granulatio...The effect of boron-on carbide morphology of high Cr ledeburite steel has been studied. The results showed that B had obvious influence on eutectic carbide morphology in solidification structure and carbide granulation at high temperature. The addition of 0.02 similar to 0.05 wt pet B changed carbide morphology in solidification structure from strip eutectic and rosette eutectic into divorced eutectic. B accelerated carbide granulation through increasing unstability and lattice distortion of carbide and element diffusion, Granular carbide could be achieved when heated at 1150 degrees C for 1.5 h.展开更多
文摘A theoretical model has been established for calculating the infiltration pressure of metal melt into the preform of ceramic fibers according to the basic principle of hydromechanics. There are three forces acting on the infiltration process in the model, i.e. viscous friction, capillary force, and gravity. The effects of the volume fraction of fibers (V-f) and infiltrating depth on the infiltration pressure are discussed. the results show that the infiltration pressure increases with tile increase of fiber volume fraction and infiltration depth. There is a linear relationship between infiltration pressure and infiltration depth. The effect of gravity on the infiltration pressure can be ignored.
文摘Influence of Ti on MC carbide of M2 high speed steel was investigated by experimental observation, thermodynamic calculation and crystallographic calculation. With addition of Ti into M2 steel, large quantities of dispersed TiC particles formed in the steel melt at higher temperature than that of the formation of MC carbide. TiC can act as heterogeneous nuclei for the crystallization of MC carbide particles, and therefore promote the formation of blocky MC carbide.
文摘The effect of boron-on carbide morphology of high Cr ledeburite steel has been studied. The results showed that B had obvious influence on eutectic carbide morphology in solidification structure and carbide granulation at high temperature. The addition of 0.02 similar to 0.05 wt pet B changed carbide morphology in solidification structure from strip eutectic and rosette eutectic into divorced eutectic. B accelerated carbide granulation through increasing unstability and lattice distortion of carbide and element diffusion, Granular carbide could be achieved when heated at 1150 degrees C for 1.5 h.
