Hot-injection techniques are currently the state-ofthe-art method for the synthesis of high-quality colloidal nanocrystals (NCs) but have typically been limited to small batch reactors. The nature of this method leads to local fluctuations in temperature and concentration where inhomogeneity due to mixing makes precise control of reaction conditions very challenging at a large scale. Therefore, development of methods to produce high-quality colloidal NCs with highthroughput is necessary for many technological applications. Herein, we report a high-quality and high-throughput NC synthesis method via a continuous microwave-assisted flow reactor where separation of nucleation and growth is demonstrated. A significant issue of microwave heating in a single-phase continuous flow microwave reactor is the deposition of in situ generated NCs on the inner wall of the reactor in the microwave zone. This deposited material leads to significantly enhanced microwave absorption and rapid heating and can result in sparking in the reactor. A gas−liquid segmented flow is used to avoid this problem and also results in improved residence time distributions. The use of this system allows for finely tuned parameters to achieve a high level of control over the reaction by separating the nucleation and growth stages.
The present study compares the effect of SiC reinforcement on densification and properties of supersolidus liquid phase sintered 6711Al-SiC composites. The prealloyed 6711 powders were mixed with SiC ranging from 5 to 20 vol.%, compacted at 400 MPa and sintered at 630ºC under vacuum. It was shown that better densification, yield strength, wear and corrosion resistance were achieved up to 10 vol.% due to uniform distribution of SiC particles throughout matrix. Beyond 10 vol.%, SiC resulted in clustering and had detrimental effect on densification and mechanical properties. Age hardening of 6711-10SiC composites led to improvement in mechanical properties
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