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101.
与球墨铸铁比较,在石墨化钢中,由于含碳量较低,因而低强度和低塑性的石墨含量较少,这就有可能采用热塑性变形和随后热处理的方法来获得较好的强度和塑性的组合。本文对石墨化钢和球墨铸铁不同热处理后性能进行了对照分析。 相似文献
102.
Relationship Between Coal Powder and Its Combustibility 总被引:1,自引:1,他引:0
Coal‘s volatile component ,ash and fixed carbon content have different function in different stages of a combustion process,but the traditional coal classification can precisely show its combustion property.In this experiment coal‘s evaluation indeves(ignition index Di),(burn off index Df) were used to qualitatively show the ignition property and combustion ending property of coal samples.Meanwhile,considering actual heating circumstances in calciner(in cement plants),this thesis established the relationship among the ignition index,burn off index and coal‘s industrial analysis value,which makes it possible for the user to predict the quality of coal before using it and is very valuable in practice. 相似文献
104.
105.
REN Ping GUAN Jianguo ZHANG Junxi 《武汉理工大学学报(材料科学英文版)》2007,22(1):168-170
Hollow spheres of hexagonal ferrite BaCozFelrO27 were fabricated through a spray pyrolysis technique using co-precipitation ferrite powder precursor as materials, followed by calcinations in an air atmosphere. The phase composition, micro-morphology, and static magnetic property of the particles were measured by XRD, SEM, and VSM. The results indicate that the method for preparation of ferrite hollow microspheres (FHM) results in a broad particles size distribution. The density of FHM decreased from 5.31 g/ cm^3 to 2.31 g/cm^3. When the heating rate was 5℃/min, and temperature was 1 200℃ for 4 hours, pure W-type ferrites were formed. With the heat treatment temperature and time increasing, the crystal structure becomes perfect, the saturation magnetization is increased and the coercive force is decreased. 相似文献
106.
钼粉还原过程对其性质的影响 总被引:1,自引:0,他引:1
钼粉的形态取决于生原料是MoOⅡNH4)Mo2O7以及还原过程所使用的还原剂,这是由于钼粉不同和产品的烧结密度、再结晶温度、强度及被损的极性有差异的结果。 相似文献
107.
108.
MoSx coatings were prepared by bipolar-pulse DC unbalanced magnetron-sputtering system with the variation of coating thickness at different Ar pressures.The composition and surface morphology were determined by using energy dispersive X-ray and scanning electron microscopy;the structural characterization was analyzed by X-ray diffraction.The friction and wear properties were investigated by fretting tests in air with less than 10% and 50% relative humidity.At 0.40 Pa pressure,(002) basal plane orientation was formed throughout the coatings.At 0.88 Pa and 1.60 Pa pressures,(002) basal plane orientation was only noticed in the first stage of coating growth(around 0.20 μm in thickness), and then edge orientations with their basal planes perpendicular to the surface would be evolved in the coatings.Humidity has a minor influence on the coatings that have(002) basal plane orientation,whereas the tribological properties of MoSx coatings with edge orientations are greatly affected by humidity.The mechanisms of coating growth and friction and wear processes are discussed. 相似文献
109.
Untextured bulk polycrystals usually possess macroscopically isotropic elastic properties whereas for most thin films transvers isotropy is expected,owing to the limited dimenionlity .The usually applied models for the calculation of elstic constants of polycrystals from single crystal elastic contants(so-called grain interaction models)erroneously predict macroscopic isotropy for an(untextured) thin film.This paper presents a summary of recent work where it has been demonstrated for the first time by X-ray diffraction analysis of stresses in thin films that elastic grain interaction can lead to macroscopically anisotropic behaviour (shown by non-linear sin^2φ plots).A new grain interaction model,predictin the macroscopically anisotropic behaviour of thin films,is proposed. 相似文献
110.
油藏条件下饱和度测井解释 总被引:1,自引:0,他引:1
石油,天然气勘探开发过程中的油气储层划分和油气储量评估主要依赖于油层原始含油饱和度及其它储层参数,评价油层原始含油饱和度主要有岩心直接测定,测井解释、毛管压力计算三种方法。其中计算饱和度最常用方法是电性模型(即Archic公式),岩电实验是其基础(获得胶结指数Ⅲ和饱和度指数等)。为了得到油(气)藏真实的饱和度数据,实验室岩电测量应尽可能在接近油(气)藏条件下进行,这些条件主要包括:温度、压力、毛管压力及流体分布平衡、润湿性等。 相似文献