Synergetic Effect of Potassium Oxysalts on Combustion and Ignition of Al/CuO Composites

In this study, we studied the synergetic effect of potassium oxysalts on combustion and ignition of nano aluminum (Al) and nano copper oxide (CuO) composites. Potassium periodate (KIO4) and potassium perchlorate (KClO4) are good oxidizers with high oxygen content and strong oxidizability. Different contents of KIO4 and KClO4 were added to nano Al/CuO and the composites were assembled by sonication. When the peak pressure of nano Al/CuO was increased ~5–13 times, the pressurization rate was improved by ~1–3 orders of magnitude, the ignition delay time was shortened by ~0.08 ms–0.52 ms and the reaction completeness was adjustable when 30–70% KIO4 and KClO4 were added into the composites. The reaction of Al/KIO4 and Al/KClO4 at a lower temperature was helpful to ignite the ternary composite. Meanwhile, CuO significantly reduced the peak temperature of oxygen released from the decomposition of KIO4 and KClO4. The synergetic effect of binary oxidizers made the combustion performance of the ternary composites better than that of the binary composites. The present work indicates that KIO4 and KClO4 are promising additives for nano Al/CuO to tune and promote the combustion performance. The ternary composites have potential application in energy devices and combustion apparatus.

A Study on the Rust Removal and Retard on the Surface of the Wear Water Screw-Thread Steel Using Flame Hot Melting

Screw-thread steel, which is produced using the quenching process through wear water controlled rolling system, would prone to generate red rust on its surface. For this reason a combustion apparatus with a smoke backflow area containing partly unburnt combustible fuel is designed to study the rusted 20MnSi wear water screw-thread steel under high temperature flame hot melting. With SEM/EDS and XRD analysis we could affirm that the main composition of the red rust is Fe2O3It assumes loose, porous branches and leaves, therefore makes the absorption of water and gas easier and intensified the sprawling of corrosion. While the steel surface after hot melting treatment form a tight passivation layer made of Fe3O4and FeO, which would isolate outer circumstance thereby protects the metal body. In the article we analyzed two main reasons that cause the red rust and point out contents that requires further studies. Compared with using chemical addition agent, this high temperature flame hot melting reaction technique is beneficial to the environment while of lower cost.