Cr-Si-Ni-N电阻薄膜的晶化与氧化特性

在PN2／PAr2分压比分别为0％，2．5％，5％，10％的溅射气氧化中制备了不同氮含量的Cr-Si-Ni-N薄膜，并研究了薄膜在热处理过程中的晶化，氧化行为以及电性能变化。结果表明，非晶Cr-Si-Ni-N薄膜在加热过程中，将析出晶化相CrSi2，随薄膜中氮含量增加，晶化相的形核与长大减缓，然而，薄膜的抗氧化能力得到提高。与低氮含量Cr-Si-Ni-N薄膜相比，高氮含量Cr-Si-Ni-N薄膜的电阻值在热处理过程中变化较小，欲获得较小电阻温度系数（TCR）需要更高的退火温度。     

Oxidation behavior of multiphase Mo5SiB2 （T2）-based alloys at high temperatures

Two MosSiB2 （T2）-based alloys with nominal compositions of Mo-12.5Si-25B and Mo-14Si-28B （molar fraction, %） were prepared in an arc-melting furnace, and their oxidation kinetics from 1 000 to 1 300 ℃ were studied. The microstructures of the alloys were characterized by X-ray diffractometry（XRD） and scanning electron microscopy（SEM） with energy dispersive spectroscopy （EDS）. The oxide scales of both alloys oxidized at 1 200 ℃ for l0 min, 2 h and 100 h were investigated by surface XRD and cross-sectional SEM-EDS. The results show that the matrix of both alloys consists of T2. The dispersions of Mo-12.5Si-25B alloy are Mo and Mo3Si, and the dispersions of Mo-14Si-28B alloy are MosSi3 （T1） and MoB. The cyclic oxidation kinetics data exhibit initial rapid mass loss followed by slow mass loss. The mass loss of Mo-12.5Si-25B alloy is much faster than that of Mo-14Si-28B alloy at 1 200 and 1 300 ~C. For l0 min exposure, both alloys form irregular and porous thin scale. For 2 h exposure, Mo-12.5Si-25B alloy forms irregular thin scale and the scale contains large cracks, and Mo-14Si-28B alloy forms sound and continuous scale. For 100 h exposure, Mo-12.5Si-25B and Mo-14Si-28B alloys form sound and continuous scale about 50-75 μm and 40-45 μm in thickness, respectively. The better oxidation resistance of Mo-14Si-28B alloy is due to a sound and continuous B-SiO2 layer formation in the early stage of oxidation.     

退火处理对ITO和ITO:Zr薄膜性能的影响

利用磁控溅射在室温条件下沉积ITO薄膜和ITO：Zr薄膜,对比研究在空气中退火处理对ITO和ITO：Zr薄膜性能的影响。结果表明,Zr的掺杂促进了（400）晶面的取向,随着退火温度的升高,薄膜表面颗粒增大,表面粗糙度有所降低。室温下Zr的掺杂显著改善了薄膜的光电性能,随着退火温度的升高,ITO和ITO：Zr薄膜的方阻都表现为先降后升的趋势,ITO：Zr薄膜在较低的退火温度下可见光透过率就可达到80%以上,直接跃迁模型确定的光学禁带宽度Eg呈现了先升后降的变化。ITO：Zr薄膜比ITO薄膜显示了更高的效益指数,揭示了ITO：Zr薄膜具有更好的光电性能。     

T122钢在服役前后的组织演变和性能评价北大核心CSCD

采用SEM、TEM及高温蠕变测试等实验方法,研究了某电厂锅炉四级过热器出口用T122管材服役前和在585~610℃服役56000 h后的组织和力学性能。结果表明:经过长时间高温服役后,T122管材的板条马氏体组织索氏体化严重,析出相聚集、长大明显,力学性能也出现较大程度下降,高温蠕变曲线及Larson-Miller参数预示服役后的管材寿命急剧缩短;考虑到T122管材服役过程中组织劣化严重,剩余服役寿命的预测并不能完全依赖于有限时间内的高温蠕变试验。