利用压痕强度法测定了SiC/BN 层状陶瓷的阻力曲线行为，并与SiC单相陶瓷做对比。结果表明：2种材料均呈现出上升阻力曲线行为，其中，SiC/ BN 层状陶瓷显示出更为优越的抗裂纹扩展能力，其阻力曲线上升较陡，上升幅度较大；SiC单相陶瓷的阻力曲线上升较缓且上升幅度较小。分析认为，这与其不同的增韧机制有关。原位增韧是SiC单相材料韧性提高的主要原因，而裂纹遇到弱界面时发生偏转、分叉、脱层等是层状陶瓷材料抗裂纹扩展能力提高的主要原因。

Ground-state structures, stabilization energies, HOMO-LUMO energy gaps, and vibrational frequencies ofGelSimCn ternary microclusters (s5l1m1n<6) have been investigated using the configuration interactionwith all single and double substitutions method, and ionization potentials and vertical detachment energies oftrimers and tetramers predicted utilizing the outer valence Green-function frozen-core procedure. GelSimCn isfound to follow structural patterns similar to corresponding Sil1mCn binary clusters and most ternary speciespossess singlet ground states except GeSiC4, which prefers a triplet one. Trimers, tetramers, and GeSi2C2 areplanar, and the C-rich GeSiC3 and GeSiC4 are linear, while all the other Si-rich or Si- and Ge-rich clusters withs>5 atoms prefer three-dimensional structures. Formation of strong CvC bonds! predominates the relativestabilities of different isomers for clusters with limited numbers of C atoms, while SivC bonds play animportant role for silicon-rich species or systems with close C and Si atomic ratios. Planar and linear semiconductorclusters possess delocalized multicenter-two-electron pbonds aromatic! and follow the (4n12)electron counting rule. Frequency analyses indicate that most vibrational modes of small ternary clusters arecarbon dominated in terms of amplitudes, while Si atoms vibrate in medium sizes and Ge atoms vibrate veryweakly.