Sue Ren

Structure formation process, heat-insulation property and cyclic compression–resilience performance of mullite fibres/whiskers frameworks

Mullite fibres/whiskers frameworks (MF/MW frameworks) were prepared by mixed-slurry-filtration and heat-treating. Hierarchical fibres/whiskers structure formed in the frameworks through fluorine-catalyzed gas-phase reaction. Topaz rods as a transient product first formed in the frameworks, and then gradually transformed into mullite whiskers. Intersected mullite whiskers served as lap-jointing points of the fibres. The volume density, apparent porosity and thermal conductivity of the samples heat-treated at 1100–1500 °C were 0.402–0.541 g cm−3, 81.2–85% and 0.1191–0.1647 W m−1 k−1, respectively. Cyclic compression–resilience performance (maximum stress = 0.4 MPa) of the samples was tested at room temperature. The compression ratio, permanent deformation ratio and resilience ratio of the samples in the first circle compression–resilience test were 2.031–3.833%, 0.125–0.042% and 93.85–98.28%, respectively. The excellent thermal/mechanical properties indicated that the MF/MW frameworks were suitable for being applied as high temperature heat-insulation/sealing materials.

Effects of Diluent on Mechanical Properties of Hollow Glass Microsphere Reinforced Epoxy Resin Composite

In order to improve the mechanical properties of hollow glass microspheres (HGMs) reinforced epoxy resin composite, diluent was added in the system of epoxy resin. The results revealed that more HGMs can be filled in the epoxy resin when appropriate amount diluent was added in the system, thus composite with relative low bulk density 0.70g/cm3 and high compressive strength 71.85MPa was obtained. It was due to that the diluent reduce the viscosity of the epoxy resin, which ensures uniform wetting of the fillers and enables more HGMs to be filled in resin. Besides, addition of diluent improved the adhesive strength between the epoxy resin and HGMs, making the composite having a relative high specific strength and can be used in weight sensitive filed.