Fabrication of multilaminated Si_3N_4–Si_3N_4/TiN composites and its anisotropic fracture behavior
Fabrication of multilaminated Si_3N_4–Si_3N_4/TiN composites and its anisotropic fracture behavior
复制标题
多层Si_3N_4–Si_3N_4/TiN复合材料的制备及其各向异性断裂行为
DOI：
10.1557/jmr.1997.0310
复制
发表时间：
1997
影响因子：
2.7
通讯作者：
H. Lu
中科院分区：
文献类型：
--
作者：
Jow;Yen Lun Chang;H. Lu
以Si_3N_4和TiN/Si_3N_4交替层合复合材料为模型材料，研究了Si_3N_4复合材料的裂纹行为和力学性能。结果表明，层合复合材料的强度和韧性均高于单片氮化硅。破坏剖面受破坏前储存的应变能和各层应力梯度的影响。由于周期性应力分布，裂纹从一层向另一层依次偏离。强度和韧性较好的试样裂纹扩展路径较长，裂纹偏差幅度较大。通过压痕裂纹长度的测量，证实了层合复合材料的周期性应力分布。结果还表明，Si_3N_4层中存在拉应力，TiN/Si_3N_4层中存在压应力，且应力方向与自由试样界面方向垂直。
Laminated composites containing alternate layers of Si_3N_4 and TiN/Si_3N_4 materials were used as model material for investigating the crack behaviors and mechanical properties. Results indicated that both strength and toughness in laminated composites were higher than that of monolithic silicon nitride. The failure profiles were affected by the stored strain energy prior to failure and the stress gradient in each layer. Cracks deviated successively from one layer to the other due to periodic stress distribution. Samples with better strength and toughness also had a longer crack propagation path and higher amplitude of crack deviation. The periodic stress distribution in laminated composites was confirmed by the measurements of indentation crack length. Results also suggested a tensile stress in the Si_3N_4 layer and compressive stress in the TiN/Si_3N_4 layer, in directions normal to the free sample interface.