Porous Si3N4 were fabricated by carbothermal reduction between carbon black and diatomite. Diatomite is a non-metallic mineral composed of skeletal remains of single-cell water plants (algae). The main ingredient of diatomite is the amorphous active SiO2. The influence of sintering additives on the microstructure and mechanical properties of porous Si3N4 was analyzed. X-ray diffraction (XRD) analysis demonstrated the formation of Si3N4 except for minor of glass phase. Scanning electron microscope (SEM) analysis showed that porous β-Si3N4 occupied fine microstructure and uniform pore structure. The addition of Y2O3 accelerated the densification of porous Si3N4 ceramics. With an increase in the content of Y2O3, the porosity decreased, the flexural strength increased, and the aspect ratio of β-Si3N4 grains became smaller accordingly. The sample with addition of 1wt% Y2O3 showed finer β-Si3N4 grains with higher aspect ratio. Porous Si3N4 ceramics with the porosity of 70.1-79.5% and the flexural strength of 2.3-14.5 MPa were obtained by this technique. This technique would provide an innovatory approach to the synthesis of porous β-Si3N4 at a drastically reduced processing cost.View full textDownload full textKeywordsCeramics, Mechanical properties, Microstructure, Porosity, SinteringRelated var addthis_config = { ui_cobrand: "Taylor & Francis Online", services_compact: "citeulike,netvibes,twitter,technorati,delicious,linkedin,facebook,stumbleupon,digg,google,more", pubid: "ra-4dff56cd6bb1830b" }; Add to shortlist Link Permalink http://dx.doi.org/10.1080/10426910903229396
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机译：通过炭黑与硅藻土之间的碳热还原制备了多孔Si 3 N 4 。硅藻土是一种非金属矿物，由单细胞水生植物（藻类）的骨骼残留物组成。硅藻土的主要成分是非晶态活性SiO 2 。分析了烧结助剂对多孔Si 3 N 4 组织和力学性能的影响。 X射线衍射（XRD）分析表明，除了微量的玻璃相外，还形成了Si 3 N 4 。扫描电镜（SEM）分析表明，多孔β-Si 3 N 4 具有良好的微观结构和均匀的孔结构。 Y 2 O 3 的加入促进了多孔Si 3 N 4 陶瓷的致密化。随着Y 2 O 3 含量的增加，孔隙率降低，抗弯强度增加，β-Si 3 N 4 晶粒相应变小。添加1wt％Y 2 O 3 的样品显示出更细的δ-Si 3 N 4 晶粒长宽比。通过该技术获得了孔隙率为70.1-79.5％，抗弯强度为2.3-14.5 MPa的多孔Si 3 N 4 陶瓷。该技术将以大幅度降低的加工成本为多孔α-Si 3 N 4 的合成提供创新的方法。查看全文下载全文关键字陶瓷，机械性能，微观结构，孔隙度，烧结相关变量var addthis_config = {ui_cobrand：“泰勒和弗朗西斯在线”，servicescompact：“ citeulike，netvibes，twitter，technorati，delicious，linkedin，facebook，stumbleupon，digg，google，更多”，发布：“ ra-4dff56cd6bb1830b”} ;添加到候选列表链接永久链接http://dx.doi.org/10.1080/10426910903229396
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