Thermal stability of nanostructured NiCrC coating prepared by HVAF spraying of cryomilled powders
来源期刊：Rare Metals2008年第4期
论文作者：CUI Hua a, TAO Kai b, ZHOU Xianglin b, and ZHANG Jishan b a School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing , China b State Key laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing , China
文章页码：418 - 424
摘 要：Thermal stability of nanostructured NiCrC coating prepared by high velocity air-fuel （HVAF） spraying of cryomilled feedstock powders was investigated. Transmission electron microscopy （TEM）, differential scanning calorimetry （DSC）, and X-ray diffraction （XRD） were utilized for characteristic analysis. Recrystallization and normal grain growth occur when isothermal treatment is performed at 923 K （0.55 TM） for up to 100 h, and the average grain size increases from initial 41 nm for as-deposited state to around 100 nm for nearly equilibrium state. Iso-chronal treatment at 823 K and 1023 K was also conducted for comparison. Accordingly, for 0.49 to 0.61 T/TM, the time exponent n deduced from D 1/n-D 1/n 0= ktincreases from 0.15 to 0.30. The observed high thermal stability is attributed primarily to a Zener pinning mechanism arising from the fine Cr2O3 dispersions and the solute drag effect as well.
摘要：Thermal stability of nanostructured NiCrC coating prepared by high velocity air-fuel （HVAF） spraying of cryomilled feedstock powders was investigated. Transmission electron microscopy （TEM）, differential scanning calorimetry （DSC）, and X-ray diffraction （XRD） were utilized for characteristic analysis. Recrystallization and normal grain growth occur when isothermal treatment is performed at 923 K （0.55 TM） for up to 100 h, and the average grain size increases from initial 41 nm for as-deposited state to around 100 nm for nearly equilibrium state. Iso-chronal treatment at 823 K and 1023 K was also conducted for comparison. Accordingly, for 0.49 to 0.61 T/TM, the time exponent n deduced from D 1/n-D 1/n 0= ktincreases from 0.15 to 0.30. The observed high thermal stability is attributed primarily to a Zener pinning mechanism arising from the fine Cr2O3 dispersions and the solute drag effect as well.
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