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991.
Daming ChenYingli Liu Yuanxun LiWenguo Zhong Huaiwu Zhang 《Journal of magnetism and magnetic materials》2011,323(22):2837-2840
In this article, the influences of the BaCu(B2O5) (BCB) additive on sintering behavior, structure and magnetic properties of iron deficient M-type barium ferrite Ba(CoTi)xFe11.8−2xO19 (BaM) have been investigated. It is found that the maximum sintered densities of BaM change from 86% to 94% as the BCB content varies from 1 to 4 wt%. Single-phase BaM can be detected by the XRD analysis in the sample with 3 wt% BCB sintered at 900 °C, and the microstructure is hexagonal platelets with few intragranular pores. This is attributed to the formation of the BCB liquid phase. Meanwhile, the experimental results illuminate that the CoTi ions prefer to occupy the 4f2 and 2b sites and the magnetic properties depend on the amount of CoTi-substitution. In addition, the chemical compatibility between BaM and silver paste is also investigated; it can be seen that BaM is co-fired well with the silver paste and no other second phase is observed. Especially, the 3 wt% BCB-added Ba(CoTi)0.9Fe11O19 sintered at 900 °C has good properties with the sintered density of 4.9 g/cm3, saturation magnetization of 49.7 emu/g and coercivity of 656.6 Oe. These results indicate that it is cost effective in the production of Low Temperature Co-fired Ceramics (LTCC) multilayer devices. 相似文献
992.
采用传统的固相反应法和普通的烧结工艺,分别制备了(Ko.48Nao.52)1-χ。(LiSb)χNb1-O3(χ=0.055,0.060,0.065)和χ=0.055,0=0.065按摩尔比1:1复合的无铅压电陶瓷样品(55-65),并对样品的压电、介电等性能进行了测试研究.实验结果表明:55-65不等同于χ=0.060的组分,其压电性能远低于χ=0.060的样品,进一步研究表明,相同烧结温度下,55-65样品的损耗较高,晶粒难以生长,相对较小,较小的晶粒可能在样品形变时产生的应力较大,这可能是55—65 相似文献
993.
Julien Lumeau Alexander Sinitskii Larissa Glebova Leonid B. Glebov Edgar D. Zanotto 《Journal of Non》2009,355(34-36):1760-1768
We describe a new method for the study of both optical and crystallization homogeneity of partially crystallized glasses or glass–ceramics at different spatial scales (from 100 mm to 1 μm). The method relies on the association of different techniques, such as interferometry, optical microscopy and differential scanning calorimetry. The method was tested to probe the optical and crystallization homogeneity of both as-made and UV-exposed, and pre-nucleated samples of a photo-thermo-refractive (PTR) glass. This study demonstrates that pure UV-exposure did not lead to an improvement of the crystallization homogeneity of the glass. However, the benefit of associating UV-exposure and nucleation thermal treatment was clear. These combined treatments permit to homogenize the crystal distribution in PTR glass at millimeter and micron scale. This result is of major commercial interest. 相似文献
994.
Weibin Chen Yuzhen Wang Jian Xu Xinrong Chen Ole B. Jensen Qinyuan Zhang Zhiguo Xia 《Laser \u0026amp; Photonics Reviews》2024,18(2):2300963
Laser-driven phosphor-converted white-laser diodes are supposed to be next-generation high-brightness lighting sources for their unparalleled photoelectric efficiency and light quality, yet a significant obstacle hitherto has resided in the shortage and serious laser-induced luminescence saturation of red emitters. Here, a hot-pressing synthesis route to obtain high-performance red-emitting cordierite (Mg2Al4Si5O18:Eu2+) ceramic is developed, which enables the in situ formation of bulk specimens with high crystallinity (>90%) from the counterpart glass powders. A preeminent saturation threshold of 21 W mm−2 is realized in a red-emitting Mg2Al4Si5O18:Eu2+ ceramic film converter. More importantly, the luminous exitance reaches 209 lm mm−2, which is 5 times that of commercial red phosphor-converted-LED, indicating breakthrough progress in the comprehensive light-emitting performance of red converters. This work innovates the solid-state synthesis of laser bulk converters from glass to meet the demanding requirements of advanced warm white laser lighting. 相似文献
995.
采用固相反应法制备了Nd:YAG透明陶瓷,并通过碳铵沉淀法处理Y_2O_3商业原料,进一步提高了Nd:YAG透明陶瓷的透明度. 结果表明:采用高纯的商业原料,通过固相法制备获得的透明陶瓷,在1 064 nm处光线直线透过率可达到74%左右;通过碳铵共沉淀法改良商业Y_2O_3粉体原料的性能,透明陶瓷的透过率可进一步提升,在1 064 nm处光线直线透过率高达78%. 相似文献
996.
根据工程陶瓷的系统高效深磨试验,研究发现:在高效深磨条件下,磨削氧化锆和氧化铝的材料去除方式不同,分别为塑性成形去除和脆性断裂去除;最大未变形切屑厚度增大至超过临界切深后,其对氧化锆的单颗磨粒法向磨削力的线性增长规律影响很小,而使氧化铝的单颗磨粒法向磨削力的增长趋势逐渐变缓;切向磨削力主要由滑擦和塑性耕犁作用引起的摩擦力组成. 相似文献
997.
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1000.
根据研究模型首先得出压电陶瓷极化特性的理论推测,然后使用DP-5型介电谱仪,测量由压电陶瓷材料制作的蜂鸣器。实验测出压电陶瓷的极化方式与极化率和外场频率有关,随着频率的增加,压电陶瓷的离子位移极化率、电介质分子取向极化的极化率将减小,最终表现为相对介电常数减小。实验结果与理论猜测吻合。 相似文献