焦洪震
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高文莉
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章建荣
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都有为
材料研究学报
将Fe—M(M=C,SiO2,Al2O3)混合物在Ar中高能球磨56h后测量Mossbauer谱.结果表明,(Fe)2-(SiO2)1仍为Fe和SiO2的机械混合物;(Fe)7-(C)3已完全合金化,生成两种Fe3C;(Fe)2-(Al2O3)1则成为Fe(73%)、尖晶石型的FeAl2O4(22%)、金属Fe的团簇(5%)和Al2O3的混合物.
关键词:
机械合金化
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Mossbauer spectroscopy
M. Siddique
材料科学技术（英文）
Mossbauer spectroscopy has been used to study the morphology of iron oxides formed during the oxidation of superalloys, such as SS-304L (1.4306S), Incoloy-800H, Incoloy-825, UBHA-25L, Sanicro-28 and Inconel-690, at 1200°C exposed in air and steam environments for 400 h. The basic aim was to identify and compare the iron oxides qualitatively and quantitatively, formed during the oxidation of these alloys in two environments. The behaviour of alloy UBHA-25L in high temperature oxidation in both environments indicates that it has good oxidation resistance especially in steam, whereas Sanicro-28 has excellent corrosion resistance in steam environment. In air oxidation of Inconel-690 no iron oxide, with established MÄossbauer parameters, was detected.
关键词:
Superalloys
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Ying Zhang Jun Lin Dijiang Wen
材料科学技术（英文）
Ferrite compound Co0:6Zn0:4NixFe2-xO4 was synthesized by solid state reaction. The structure and performance of Co0:6Zn0:4NixFe2-xO4 compounds were studied by MÄossbauer spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and infrared radiant tester. MÄossbauer spectroscopy and XPS analysis show the valence states and distribution of cations in Co0:6Zn0:4NixFe2-xO4. Zn2+ has invariably shown preference for the tetrahedral sites, and Ni2+ has the preference for the octahedral sites. The occupancy of Fe3+ linearly increases on the tetrahedral sites, and sharply decreases on the octahedral sites with increasing x, owing to its gradual replacement by Ni2+ on the octahedral sites. It indicates that due to the occupation of octahedral sites by the majority of Ni2+, Fe3+ decreasingly migrated from the octahedral sites to the tetrahedral sites and substituted Co3+ sites, which made the number of Co3+ in the tetrahedral sites decreasing. According to the measurement results of XRD and the infrared radiant tester analysis, the lattice parameter and infrared radiance have shown a nonlinear variation, exhibiting the infrared average radiance of 0.92 in the 8-14 μm waveband, and the results demonstrate that these Co-Zn-Ni spinel ferrites have potential for application in a wide range of infrared heating and drying materials.
关键词:
Infrared radiance
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