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21.
《Ceramics International》2016,42(16):18031-18036
Facile and scalable synthesis method of MgO/Carbon Black nano-admixture as an additive for MgO/C refractory bricks has been developed via simple precipitation method. The main idea of the present work lies on the precipitation of magnesium hydroxide in well dispersed/stabilized carbon black nanoparticle suspension resulting in Mg(OH)2/CB nano-admixture preparation. Furthermore, applying such colloidal suspension of CBs prevent the sever agglomeration of Mg-containing precipitate and make simple precipitation method as a reliable synthesis method of nano-structured MgO. Finally, different analytical methods including X-ray diffractometer, Scanning electron microscopy, Cold crushing strength and physical properties measurement have been utilized to study the effect of such nano-admixture on the microstructural and mechanical properties of typical MgO/C refractory bricks.  相似文献   
22.
正The Most Professional Manufacturer of Refractory Electric Screw Press in ChinaZibo Sangde Machinery Equipment Co.,Ltd.is the first Manufacturer of Refractory Electric Screw Press in China,in the year of 2008,our company produced the first set 315T Refractory Electric Program-controlled Screw Press in China,which is no friction discs,simple structure,with PLC controlling the brick forming process,no need special operator.Once upon the Press was on the market,it achieved a strong interests and reputations from many Refractory Factories because of its Highefficient,Energy-saving(can save by 40-50%electricity comparing to the Friction Press),manpower reduction and improving the quality of bricks.  相似文献   
23.
《Ceramics International》2016,42(7):8431-8437
This study aims to investigate the effect of sintering temperatures on the phase formation and physical characteristics of refractory cordierite prepared from rice husk silica, Al2O3, and MgO powders. The samples were subjected to sintering temperatures of 1050–1350 °C, and development of structures was characterized using Fourier Transform Infrared (FTIR) spectroscopy, X-ray diffraction (XRD) coupled with Rietveld analysis, scanning electron microscopy (SEM) and dilatometry. The results obtained indicated the significant role of sintering temperatures on phase transformation of spinel and cristobalite into cordierite, in which at sintering temperatures of 1230–1350 °C the cordierite emerges as a dominant phase, while spinel and cristobalite are practically undetected. Formation of cordierite was followed by decrease in density, porosity, and thermal expansion coefficient, while for hardness and bending strength the opposite was true. Thermal expansion coefficient of the sintered sample at 1350 °C is 3.3×10−6/°C and the XRD analysis demonstrated that the main crystalline phase is cordierite. Based on these characteristics, the samples are considered as insulator, suggesting their potential use in refractory devices.  相似文献   
24.
In the present study, the effects of Nb addition on Charpy impact properties of TiVTa refractory high-entropy alloy with high strength-ductility trade-off were systematically studied by using the instrumented Charpy impact testing machine. The experimental results showed that the impact toughness was remarkably improved by Nb addition in TiVTa to form TiVTaNb alloy. The crack initiation energy and propagation energy of TiVTaNb were 67.3% and 24.9% higher than that of TiVTa, indicating that Nb addition simultaneously reinforced the resistance to crack initiation and propagation. The impact fracture of TiVTaNb exhibited larger bending degree of shear lips, deeper dimples and more secondary cracks which effectively dissipated more impact energy. The deformation mechanism of TiVTa alloy was dominated by dislocation activities. While in TiVTaNb, the deformation mechanism was synergized by dislocation activities and deformation twinning, which were the main contributors for the improved impact properties and the stronger crack resistance of TiVTaNb alloy under impact loading.  相似文献   
25.
A series of Ti_2ZrHf_(0.5)VNb_x( x = 0, 0.25, 0.5, 0.75 and 1.0) refractory high-entropy alloys were prepared to investigate the alloying effect of Nb on the microstructures and mechanical properties.All the alloys displayed a simple BCC structure.The microstructures of the alloys changed from the initial single-phase columnar structure( x = 0) to dendrite microstructure( x 0).At room temperature, all the alloys exhibited high ductility(with the compressive strains of more than 50%).With the increase in Nb content, the yield strength slightly decreased from 1160 to 980 MPa and the hardness dropped from 338 to 310 HV.Moreover, the alloys exhibited low density from 6.47 to 6.84 g/cm~3 and high specific yield strength(SYS) from 143 to 179 kPa m~3/kg.The comprehensive performance of ductility and SYS was superior to most of the reported highentropy alloys.The yield strength of the alloys increased from 405 to 859 MPa and from 85 to 195 MPa with the addition of Nb element at 873 K and 1073 K, respectively.  相似文献   
26.
某含砷高硫难处理金矿固砷固硫提金试验   总被引:4,自引:0,他引:4  
对某地含砷高硫难处理金矿 ,进行了固化焙烧——氰化浸出工艺流程的试验研究 ,获得了硫的固化率达 95 .5 5 % ,砷的固化率为 95 .4 9% ,金的浸出率为 93.18%的较好技术指标。为含砷高硫类型金矿资源的开发利用提供了较新的途径  相似文献   
27.
Molybdenum and a molybdenum alloy were fusion welded to ZrB2-based ceramics to determine if the electrical and thermal properties of the metals and ceramics affected their weldability. Commercial ceramic powders were hot pressed, machined into coupons, and preheated to 1600 °C before joining the ceramics to commercial metals using plasma arc welding. Weldability varied as indicated by the range of porosity observed within the fusion zones. Measured thermal and electrical properties appeared to have little to no effect on the weldability of metal-ceramic welds despite the large range of values measured across each property. Differences in melting temperatures between metal and ceramic coupons did affect weldability by changing the weld penetration depth into ceramic coupons. Future studies on metal-ceramic welds are suggested to investigate the effect that work function, melt viscosity, wetting, or other properties have on weldability.  相似文献   
28.
分析了石灰窑耐火材料脱落原因,采取了重新选择耐材材质、设计砖型、新型隔热材料应用及改进措施等,实现了石灰窑耐火材料使用寿命的延长,使石灰窑筒体煅烧带表面温度降低到350℃以下,最终降低了石灰生产成本。  相似文献   
29.
正The Most Professional Manufacturer of Refractory Electric Screw Press in ChinaZibo Sangde Machinery Equipment Co.,Ltd.is the first Manufacturer of Refractory Electric Screw Press in China,in the year of 2008,our company produced the first set 315T Refractory Electric Program-controlled Screw Press in China,  相似文献   
30.
β-Sialon结合刚玉耐火材料的合成   总被引:3,自引:6,他引:3  
本研究对βSialon结合刚玉的合成反应进行了热力学分析。并通过改进合成工艺,制备出了氮含量为8.0%,气孔率13.4%,体积密度3.04g·cm-3,耐压强度164.8MPa的试样。试样的XRD分析表明,其主晶相为刚玉和βSialon,杂质相含量很少。SEM分析显示,试样的结构致密,刚玉颗粒与基质中的βSialon之间的结合牢固  相似文献   
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