Y.C. Ma
材料科学技术（英文）
A study was conducted to examine the isothermal oxidation behavior of a new Ni-Cr-W-Al alloy in air at 1250°C with different time. Oxidation kinetics was determined from weight-change measurements. The microstructure and composition of the oxide scale were investigated by means of scanning electron microcopy and X-ray diffraction. The results showed that the oxide scales of the alloy were a compact and continuous outer Cr2O3 and NiCr2O4 layer and an inner Al2O3 layer that was in dendrite shape. Oxides scales with good adherence were formed on the surface of the alloy, which made the alloy perform excellent high-temperature oxidation resistance.
关键词:
Oxidation kinetics
,
null
,
null
Y.C. Ma
材料科学技术（英文）
A study was conducted to examine the isothermal oxidation behavior of a new Ni-Cr-W-Al alloy in air at 1250°C with different time. Oxidation kinetics was determined from weight-change measurements. The microstructure and composition of the oxide scale were investigated by means of scanning electron microcopy and X-ray diffraction. The results showed that the oxide scales of the alloy were a compact and continuous outer Cr2O3 and NiCr2O4 layer and an inner Al2O3 layer that was in dendrite shape. Oxides scales with good adherence were formed on the surface of the alloy, which made the alloy perform excellent high-temperature oxidation resistance.
关键词:
Oxidation kinetics
,
null
,
null
郭红丽
,
孙庚辰
,
石干
,
杜军卫
耐火材料
doi:10.3969/j.issn.1001-1935.2004.06.006
以电熔镁砂、电熔白刚玉和烧结尖晶石等为原料,研究了尖晶石的加入量(0,5%,10%,15%,20%,30%)和加入形式(≤0.044 mm的细粉或<2mm的颗粒)对不烧MgO-MA-C及Al2O3-MA-C质耐火材料抗氧化性的影响.结果表明:MgO(Al2O3)-MA-C质耐火材料的抗氧化性开始随着尖晶石细粉的加入逐渐变强,尖晶石细粉的加入量为5%～10%时抗氧化性最好,当尖晶石细粉的加入量再继续增加时,抗氧化性变差;固定尖晶石加入量为10%,尖晶石以细粉形式加入时,试样的抗氧化性最好,逐渐加大尖晶石的粒度,试样的抗氧化性变差;MgO-MA-C质耐火材料的抗氧化性比Al2O3-MA-C质耐火材料的抗氧化性好.
关键词:
尖晶石,不烧MgO(Al2O3)-MA-C耐火材料,抗氧化性
薛军柱
耐火材料
doi:10.3969/j.issn.1001-1935.2011.02.008
以高纯电熔镁砂、镁铝尖晶石微粉和纳米炭素为主要原料,分别加入总量为4%(质量分数)的硅粉、铝粉和硅粉-铝粉复合粉为防氧化剂,加入清洁的自来水混练均匀后,在500 t 摩擦压砖机上成型为碳质量分数小于1%的超低碳MgO-MA-C 标型砖试样.在对比各试样(包括普通MgO-C砖试样)的抗氧化性能、高温抗折强度、体积稳定性和抗渣性的基础上,对配方和生产工艺进行了优化,研制出了性能较好的超低碳(碳质量分数小于1%)MgO-MA-C砖.所研制砖在武钢200 t转炉钢包渣线区使用,平均使用次数达75次.
关键词:
钢包
,
渣线
,
超低碳
,
方镁石-尖晶石-碳砖
,
纳米碳
李友胜
,
张唐文
,
李楠
耐火材料
doi:10.3969/j.issn.1001-1935.2007.03.007
以电熔白刚玉、镁铝尖晶石、SiC细粉、活性α-Al2O3微粉、球状沥青、Si粉、ρ-Al2O3、氧化硅微粉和铝酸钙水泥为原料制备了Al2O3-MA-SiC-C质浇注料.振动浇注成型后采用静态坩埚法测定了浇注料抗渣侵蚀性,利用X射线衍射、电子探针仪和能谱等手段分析了1500 ℃埋炭处理3 h后试样的物相、显微结构和微区成分,以研究结合剂种类(ρ-Al2O3+氧化硅微粉和铝酸钙水泥+氧化硅微粉)、尖晶石和SiC的加入量对浇注料抗渣性能的影响.结果表明:采用ρ-Al2O3+氧化硅微粉结合的浇注料的抗渣性能明显高于采用铝酸钙水泥+氧化硅微粉结合的,这主要与其在高温下形成的物相有关;随着镁铝尖晶石加入量的增多,浇注料的抗渣性能总体上呈升高趋势;随着SiC加入量的增多,浇注料的抗渣性能显著提高,当SiC加入量(质量分数,下同)为25%时,浇注料的抗渣性能最好;加入过多的镁铝尖晶石和SiC对浇注料的抗渣性能不利,这主要同高温下材料中MgO-Al2O3-SiO2系低熔物的形成有关.
关键词:
出铁沟
,
浇注料
,
结合剂
,
镁铝尖晶石
,
SiC
,
抗渣性
Physics Letters A
The magnetic properties of the mixed ferro-ferrimagnetic compounds with (A(a)B(b)C(c))(y)D, in which A, B, C and D are four different magnetic ions and form four different sublattices, are studied by using the Ising model. And the Ising model was dealt with standard mean-field approximation. The regions of concentration in which two compensation points or one compensation point exit are given in c-a, b-c and a-b planes. The phase diagrams of the transition temperature T-c and compensation temperature T-comp are obtained. The temperature dependences of the magnetization are also investigated. Some of the result can be used to explain the experimental work of the molecule-based ferro-ferrimagnet ((NiaMnbFecII)-Mn-II-Fe-II)(1.5) [Cr-III (CN)6] - zH(2)O. (C) 2003 Elsevier B.V. All rights reserved.
关键词:
mixed ferro-ferrimagnet;Ising model;four sublattices;phase diagram;transition temperature;compensation temperature;magnetic-properties;prussian blue;alloy
Corrosion Science
The oxidation of pure Co and two Co-Y alloys containing 2 at.% and 5 at.% Y has been studied at 600-800 degrees C in air. The oxidation of pure cobalt at all temperatures followed the parabolic rate law. The oxidation of the two alloys approximately followed the parabolic rate law at 800 degrees C, but was closer to cubic behavior at 600 and 700 degrees C except Co-5Y at 600 degrees C, which deviated from the cubic and parabolic rate law. The corrosion of both alloys at the three temperatures produced an external scale containing Co oxides (Co3O4, CoO) and Y2O3 and an internal oxidation region where Co17Y2 was converted into Co and Y2O3. The distribution of Y2O3 closely followed that of the intermetallic compound (Co17Y2) in the original alloy. The corrosion mechanism of the alloys is examined. (C) 1999 Elsevier Science Ltd. All rights reserved.
关键词:
Co;Y;oxidation;high-temperature oxidation;possible scaling modes;internal oxidation;oxidant pressures;h-2-h2s mixtures;sulfidation;oxygen
Oxidation of Metals
The oxidation of Fe- Y alloys containing 2 and 5 at.% Y and pure iron has been studied at 600-800 degrees C in air. The oxidation of pure iron follows the parabolic rate law at all temperatures. The oxidation of Fe-Y alloys at 600 degrees C approximately follows the parabolic rate law, but not at 700 and 800 degrees C, where the oxidation goes through several stages with quite different rates. The oxide scales on Fe-2Y and Fe-5 Y at 700 and 800 degrees C are composed of external pure Fe oxides containing Fe2O3, Fe3O4, and FeO, with FeO being the main oxide and an inner mixture of FeO and YFeO3. The scales on Fe-2Y and Fe-5Y at 600 degrees C consist of Fe2O3, Fe3O4, and Y2O3, with a minor amount of FeO. Significant internal oxidation in both Fe-Y alloys occurred at all temperatures. The Y-containing oxides follow the distribution of the original intermetallic compound phase in the alloys. The effects of Y on the oxidation of pure Fe are discussed.
关键词:
pure Fe;Fe-Y alloys;oxidation;high-temperature oxidation;possible scaling modes;2-phase;binary-alloys;low-oxygen pressures;oxidant pressures
李鹏
,
胡耀波
,
熊惟皓
,
林真
硬质合金
doi:10.3969/j.issn.1003-7292.2000.02.001
研究了稀土元素Y对Ti(C,N)基金属陶瓷微观组织和性能的影响.Y在Ti(C,N)基金属陶瓷中可以起到净化粘结相/硬质相界面的作用,并使其包覆层的厚度略有增加,从而使硬质相颗粒得到细化.当Y含量为0.8wt%时细化效果最明显,此时Ti(C,N)基金属陶瓷的抗弯强度和硬度值最大.
关键词:
稀土元素
,
Y
,
金属陶瓷
,
组织与性能
Journal of Applied Physics
The magnetic properties of R2Co14B1-xCx (x=0, 0.5 and R=Y, Sm) compounds have been studied by measuring the temperature dependence of the easy- and hard-magnetization curves on magnetically aligned samples between 1.5 and 300 K for Y2Co14(B,C) and at 4.2 K for Sm2Co14(B,C). The magnetic anisotropy of Y2Co14B increases due to the substitution of C for B, whereas the saturation magnetization decreases. Between 1.5 and 300 K, the anisotropy field of Y2Co14B0.5C0.5 increases about 2 T and the Co moment decreases about 0.05mu(B). The anisotropy field Of Sm2Co14B also increases upon C substitution and the saturation magnetization decreases slightly. The ac susceptibilities of both SM2Co14B and Sm2Co14B0.5C0.5 exhibit anomalies that may arise from a spin reorientation within the basal plane.
关键词:
nd2fe14b;exchange;nd2co14b;r2fe14b;field
