金属熔体、陶瓷增强相在超声作用下的润湿与复合

Metal matrix composites (MMCs) reinforced by micro- or submicro-sized ceramic particles without chemical reactions along the particles/matrix interfaces can be produced efficiently using high-intensity ultrasonic vibrations. MMCs thus obtained possesse good mechanical properties. The relation between volume fraction and size of the reinforced particles and the MMCs' properties (E, σb, Hv and δ) and the relation between apparent viscosity of the melt and reinforcement sizes were obtained. By SEM in-situ observation of fracture process during tensile testing and the analysis of the internal stress field in the composite, it was found that the increase of ultimate strength results from a combined effect of strain and stress hardening of the matrix. By combining exothermic dispersion method with ultrasonic dispersion techniques, the composites reinforced by nano-sized ceramic particles could be produced, which possess both high strength and good ductility.

将超声波引入座滴法界面张力测量系统，实时、定量测量金属熔体－陶瓷增强相界面润湿性随超声能量与作用时间的变化规律。系统、深入地研究超声参量对界面的微观结构、成分和性能的影响。上述研究可从本质上揭示超声改善金属熔体－陶瓷润湿性的机制，填补有关理论空白，并为高性能金属基复合材料的制备提供重要的理论与实验依据。