The behaviors of different inhibitors including their composition, size, distribution, coalescence and coarsening were experimen-tally studied. It was observed that during secondary recrystallization of the tested ste...The behaviors of different inhibitors including their composition, size, distribution, coalescence and coarsening were experimen-tally studied. It was observed that during secondary recrystallization of the tested steel, the key inhibition effect was produced by Cu2S and AlN, but not MnS. With the increase of temperature, the size distributions of AlN and Cu2S were changed to some extent. However, signifi-cant changes in particle size were not observed. The initial temperature of abnormal growth was determined by measuring the evolution of particle sizes and their distribution density during heat treatment. AlN and Cu2S are the dominant inhibitors and both are necessary, which is verified by calculating the Zener factor.展开更多
A typical Ti（C, N）-based cermet and another cermet with grain growth inhibitor Cr3C2 were studied using scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, energy dispersive X-ray analys...A typical Ti（C, N）-based cermet and another cermet with grain growth inhibitor Cr3C2 were studied using scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, energy dispersive X-ray analysis （EDX）. The two cermets have a “core-rim” structure. The structure is formed by dissolution of small ceramic grains and precipitation of （Ti, Mo, W）（C, N） around the remaining TiC core. Most of chromium element congregated in the rim phase when Cr3C2 was added. During liquid phase sintering Cr3C2 solved in binder phase and congregated around the hard grains, which reduced the solubility of TiC in liquid phase, and consequently restrained the dissolution and reprecipitation, the grains were restrained from growing up during sintering.展开更多
基金supported by the National Natural Science Foundation of China (No.50871015)
文摘The behaviors of different inhibitors including their composition, size, distribution, coalescence and coarsening were experimen-tally studied. It was observed that during secondary recrystallization of the tested steel, the key inhibition effect was produced by Cu2S and AlN, but not MnS. With the increase of temperature, the size distributions of AlN and Cu2S were changed to some extent. However, signifi-cant changes in particle size were not observed. The initial temperature of abnormal growth was determined by measuring the evolution of particle sizes and their distribution density during heat treatment. AlN and Cu2S are the dominant inhibitors and both are necessary, which is verified by calculating the Zener factor.
文摘A typical Ti（C, N）-based cermet and another cermet with grain growth inhibitor Cr3C2 were studied using scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, energy dispersive X-ray analysis （EDX）. The two cermets have a “core-rim” structure. The structure is formed by dissolution of small ceramic grains and precipitation of （Ti, Mo, W）（C, N） around the remaining TiC core. Most of chromium element congregated in the rim phase when Cr3C2 was added. During liquid phase sintering Cr3C2 solved in binder phase and congregated around the hard grains, which reduced the solubility of TiC in liquid phase, and consequently restrained the dissolution and reprecipitation, the grains were restrained from growing up during sintering.
