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In this paper, to improve the hot deformability and corrosion resistance, a nanoamorphous B2O3 layer was designed and fabricated between B4C particles and an Al matrix successfully. The B4C@B2O3/Al composites were prepared by a hot-pressed sintering method. By contrast, the B4C/Al composites were synthesized using the same preparation method. The results show that the existence of an amorphous layer can effectively inhibit the formation of Al3BC, AlB12, and other reaction products at the interface, compared with B4C/Al composites. At the same time, the existence of an amorphous B2O3 layer can reduce the maximum deformation resistance of the composites under the compression conditions of 500 °C and 0.001 s–1, to about 76% lower than that of the B4C/Al composites, and improve the hot deformability significantly. Furthermore, the corrosion current density of B4C@B2O3/Al composites is 82.5% lower than that of the B4C/Al composites. The good corrosion resistance makes B4C@B2O3/Al composites a potential neutron shielding material.

In this paper, the Cf/pure Al composite and the Cf/Al–Fe–Mg–Si composite were prepared by pressure infiltration method, and the microstructure and high temperature mechanical properties of these two kinds of composites were studied. The main interface phase of the Cf/pure Al composite is Al4C3, while in the Cf/Al–Fe–Mg–Si composite, a new type of Fe-rich phase containing Al, Fe, Mn, Cr, Si and other elements with a body-centered cubic structure calibrated by TEM diffraction pattens is discovered, whose lattice constant is 1.39 nm. Results of high temperature bending tests and researches of microstructure demonstrated that, the bending strength of the Cf/Al–Fe–Mg–Si composite decreased first at room temperature to 200 °C, due to re-dissolution of nano-precipitates. Afterwards, the bending strength increased under the combined action of the stress relaxation mechanism, the crack deflection mechanism and the high temperature strengthening mechanism of the Fe-rich phase at a temperature range in 200 °C–400 °C, and reached about 880 MPa at 400 °C, which demonstrated better high temperature mechanical properties than that of the Cf/pure Al composite. The results indicated that the formation of high-temperature stable precipitates through TM alloying can effectively increase the ultimate service temperature of Cf/Al composites. The work in this paper is of great significance in the design and preparation of Cf/Al composites with excellent high-temperature properties.

This method is based on the principle of interference of lights. According to the moire cycle, the best folding angle is 0°. When overlapping angles up to 5°/10°, the maximum moire cycle is less than the graphic resolution of human eyes. The graphic/text will be deformed and not easy to be recognized. Experimentally, it selects 45 degrees screen for actual graphic with the resolution of 175~200lpi and black stripes. The width of stripe is equal to the stripe spacing about 0.0635mm. In actual graphic, text and background are both screened in the same way but opposite distribution. The graphic message is hidden in high resolution. Through camera, actual graphic is rectangular with corners for track and correction of location. If the gray feature matches threshold, identification chart as well as virtual graphic will be produced with the same screen. At a certain angle, actual graphic and virtual graphic superpose moire interference catching sight of graphic message from background, since they arise opposite interferences and enlarge division. At results, three examples of text, graphics, and text-graphics can be well recognized by virtual lamination. This method provides a new method for information encryption and retrieval.