A route to increase fracture toughness of layered Si3N4/SiC composite using interlocked interfaces

作者：Ye, Feng^*; Liu, Shichao; Hu, Shengqing; Yang, Haixia; Liu, Qiang; Zhang, Biao

来源：Ceramics International, 2015, 41(8): 10331-10335.

DOI：10.1016/j.ceramint.2015.04.102

• Mechanical property
• Multi layer composite
• Interlocked interface
• Aqueous tape casting

Multilayer Si3N4/SiC composite with interwoven interfaces was designed and prepared via the aqueous tape casting and gas pressure sintering process. This composite had relatively uniform layer thickness, high strength (similar to 564 MPa), toughness (similar to 16.8 MPa m(1/2)) and work-of-fracture (similar to 4411 J/m(2)). The first-level toughening mechanism started from the fracture surface of the multilayer composite. Obvious crack deflection was found in the Si3N4 and SiC layers. At the same time, the pullout and fractured rodlike beta-Si3N4 grains were detected along the interfaces of the composite. The growth of the rodlike beta-Si3N4 grains (the grain size > 50 mu m) along the interfaces was determined by the vapor phase transport mechanism. Both rich SiO2 on the surfaces of the SiC/Si3N4 particles and high porosity of the SiC layers were contributed to the growth of beta-Si3N4 grains.

• 出版日期2015-9
• 单位哈尔滨工业大学; 中南大学