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Hysteroscopic treatment of septate uterus with Nd:YAG laser is effective. The cervix may not be excessively dilated, the intraoperative bleeding can be thoroughly controlled, and the procedure under local anesthesia is relatively safe.

For network architecture design, stress concentration sensitivity caused by particle shape may change, which is rarely studied. Here, the particle shape dependent stress concentration and its effect on the deformation, fracture and mechanical properties were investigated. Three particle shapes including hexahedron, twenty-six face polyhedron and sphere were utilized to generate different stress distribution states in the matrix. A numerical composite model showing network architecture (like grain boundary) was applied. A strong correlation between particle shape, stress concentration factor (RSiC) and mechanical properties of network composite was built. The particle shape affected the load-bearing capability due to the stress concentration state generated at particle edges. Near the yield point, hexahedron particle wall parallel to the load direction (PaW) was more effective in carrying loads (~1000 MPa) than that of twenty-six face polyhedron (750-1000 MPa) and sphere (600-1000 MPa) particles. In network composites reinforced by different shape particles, the main crack always initiated in perpendicular network walls (PeW), but propagated along different paths: in Al matrix for hexahedron particle, along macro-interface of SiC/Al–Al for twenty-six face polyhedron particle and in PeW for sphere particle. Such crack propagation manners contributed to the different elongations of network composites by various particle shapes: sphere > twenty-six face polyhedron > hexahedron particles. Selection of round particle and adjustment of local volume fraction improved elongation with a sacrifice of modulus and strength.

A microstructure-based comprehensive finite element model, which incorporated the deformation/fracture of the matrix alloy, fracture of the particle and decohesion of interface, was built to predict the effects of particle size and shape on the plastic deformation and fracture behaviors in particle-reinforced metal matrix composites. The effect of particle size on the yield strength and work hardening rate of the matrix alloy was demonstrated. When the particle diameter is <10 µm, the fracture of the matrix alloy near the interface dominates the failure mechanism of the composite, whereas changed to particle fracture with particle diameter >10 µm. A cohesive zone model was also included in order to predict interfacial failure behavior. It was noted that SiC/Al interface exhibits a high interfacial bonding strength and the interfacial decohesion was caused by crack propagation from the particle to the interface. The simulation results are in good agreement with the experiment tensile test results in the SiCp/6061Al composite.

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