Thermal shock resistance of hot-pressed SiCw/Si3N4(w=whisker) composites was investigated by thermal shock resistance parameters and water quenching test. The results showed that the thermal shock resistance to fracture initiation and crack-stable repropagation deteriorated with increasing SiCw content in spite of the improvement of fracture toughness, K1C. This could be attributed to the great decrease of strength, σand the considerable increase of Young’s modulus, E, and thermal expansion coefficient, α,resulting from the addition of SiC whiskers. The curves of the residual strength, σ,after water quenching versus thermal shock temperature difference, △T, e.g. σ1-△T, showed good relationships with the calculated thermal stress fracture resistance parameter, R, and thermal stress crack stability parameter, Rst. The crack propagation of SiC whisker reinforced Si3N4 occurred primarily in a quasi-static manner, and it could be mainly attributable to SiC whiskers’ pulling-out and bridging toughening effects.

Nanocrystalline powder with particle size 50 nm and thin film with thickness 2 μm of SrBi2Ta2O9 (SBT) were successfully prepared by the sol–gel method, using strontium acetate semihydrate [Sr(CH3COO)2.1/2H2O] and bismth subnitrate [BiO(NO3)], and tantalum ethoxide [Ta(OCH2CH3)5] as source materials, glacial acetic and ethylene glycol as solvents. The XRD and TEM results indicated that SBT layer-perovskite phase powder obtained has to be single phase, Pt layer had a (100) predominate orientation, and the (115), (200) of SBT thin film formed after being annealed at 800 ℃ for 1 min. The typical hysteresis loop of SBT thin film on Pt/Ti/SiO2/Si was obtained, and the measured Pr and Ps values of the SBT thin film were 5.5 and 8.8 μC/cm2, respectively.

In situ TiB whiskers have a hexagonal shape in the transverse section and grow along the [010]TiB direction. The crystallographic planes of the TiB whiskers in the transverse section are always (100), (101) and (101). The stacking faults in TiB are typically with a stacking fault plane of (100)TiB. The locations of boron atoms and the lattice mismatch energy between TiB and Ti matrix play key roles in the formation of stacking faults.

The in situ TiB particle reinforced titanium metal matrix composites were prepared using MA followed by park plasma sintering (SPS) with a heating rate of 50℃/min. The in situ TiB were synthesized by chemical reaction between TiB2 and Ti during the SPS process. The microstructure of the composites sintered at 800, 1000 and 1200℃ were investigated. TiB whiskers are needle-shape and uniformly dispersed in the titanium matrix. The interface between the in situ TiB needles and the titanium matrix is singular and faceted. The composite sintered at 1000℃ has a maximum value of relative density of 99.6%, and good mechanical properties with a flexural strength of 1007 MPa, Young’s modulus of 146 GPa and fracture toughness of 8.64 MPa·m1/2, respectively. The fractographs of all composites exhibit a predominantly brittle cleavage fracture mechanism. The elastic modulus of synthesized TiB was estimated.