Jiancun RAO
,
Jiancheng GU
,
Yu ZHOU
,
Feng YE
,
Tingquan LEI
材料科学技术（英）
BAS glass-ceramic powders were prepared by sol-gel processing. SiC platelets reinforced BAS glass-ceramic matrix composites with high density and uniform microstructure could be made using hot-pressing method. The related processing parameters were studied in this work, including effects of additional seed on transformation from H to M of barium aluminosilicate. DTA method was used to determine exact time to press mixture powders during hot-pressing for the purpose of effective densification. Microstructure and mechanical properties of the composites were investigated by mean of SEM, XRD and TEM techniques as well as three points bending test and single edge notched beam measurement. The results showed that the flexural strength and fracture toughness value of the BAS glass-ceramic matrix composites could be effectively improved by the addition of the SiC platelets. But the relative densities of composites were slightly decreased. The main toughening mechanism is crack deflection, platelets' pull-out and bridging. The increased value of flexural strength is contributed to the load transition effect from matrix to SiC platelets.
关键词:
Jiancun RAO
,
Yu ZHOU
,
Douxing LI
材料科学技术（英）
A new type of long periodic structure has been found in ZrO2-Y2O3 ceramics in annealed states. High resolution electron microscopy (HREM), selected area electron diffraction, and computer simulation have been used to reveal the presence of the long periodic structure. The unit cell of the long periodic structure consists of a cubic ZrO2 unit cell and L10- like phase one.
关键词:
Ceramics
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