The effects of nano-diamond seeds on the performance of diamond-like carbon (DLC) films were investigated. In this study, the high uniform DLC films were deposited on substrates seeded with nano-diamond by using a magnetron sputtering system. Then, the effects of nano-diamond seeds on DLC films were determined. Raman spectroscopy revealed a decrease of sp3 fraction due to the introduction of nano-diamond seeds. Atomic force microscope (AFM) observed all samples have an average root mean square (RMS) roughness of 1.8 nm. Scanning electron microscopy (SEM) displayed that a large number of small size conical hillock geometrical anomalies can be caused by nano-diamond seeds. Indentation tests revealed that nano-diamond seeds can enhance the hardness of DLC films, whose hardness range is from 28.3 GPa to 32.1 GPa in this work.
Effect of Cr element on microstructure of Al-3.2Mg alloys was investigated using optical microscopy, scanning electron microscopy (SEM) and EDS. Moreover, the tensile and hardness test were carried out. The results show that a minor additive of Cr can refine effectively the secondary dendrite arm spacing and decrease the number of coarse interdendritic structures. In the whole series of the alloys, the secondary dendrite arm spacing of Al–3.2Mg-0.1Cr alloy was the smallest, and the spacing presented an increasing trend with the Cr content. With high levels of Cr, the intermetallic compounds are formed by Cr with Al, Mg and Fe, the shape of the second phase particles were transformed from bulky bone shape to fine bone shape and long striped. The strength and the hardness of Al–3.2Mg alloys were greatly improved when the additions of Cr were 0.05% and 0.1%, but the ductility of the alloys remained at a low level by adding 0.05%Cr. Therefore, combining with the comprehensive properties and the microstructure, the best addition of Cr in the alloy was 0.10% in the whole series.
Formation mechanism of TiC in Al matrix at a rather low melting temperature using in situ technology was studied. And effect of the melting temperature on the microstructure of in-situ TiC/Al composite was investigated. The results indicate that, the resultants of TiC and Al3Ti were found out in the matrix; however, no evidence showed that Al4C3, a resultant phase existed probably in TiC/Al composite in accordance with the relative reference, was found out. Compared to the sample of T750, more TiC and less Al3Ti existed in the sample of T850, and morphography of Al3Ti changed from block to bar with the increasing melting temperature. The melting temperature affected extremely the reaction speed and the resultants.
This study demonstrates the enhancement effect of spark discharge on laser-induced breakdown spectroscopy detection of Fe particles in transformer oil. To obtain better discharge enhancement effect and improve the quantitative...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.