Papers by Author: Chen Guang Bai

Abstract: The absorption of microwave energy has very close relationship with the structure and property of material. For the preparation of V-Al alloy with using microwave-assisted self-propagating, it is essential to choose the proper materials with suitable properties and quantities. The temperature-rise can be obtained by the interaction between microwave field and materials, and then the aluminothermic reaction can be controlled in the microwave field. In this paper, the temperature-rise behaviors of Al2O3, CaO, V2O5 and the slag after reaction under microwave field were investigated. The results showed that either the microwave power or the molecular structure of materials had significant effects on the heating rate. The relationship between temperature-rise behavior of different materials and the material structures were discussed through studying the difference of molecular structures, which led to the conclusion that the more structure defects in the crystal, the faster the heating rate was.

Abstract: Hydrogen storage in solid hydrides is the most attractive method of on-board hydrogen storage in fuel cell for cars. Mg metal exhibits a high-storage capacity by weight and has been considered a group of potentially attractive candidates for solid-state hydrogen storage. In this study, mechanochemical synthesis of nanocrystalline Mg-based hydrogen storage composites from various starting materials in specialized hydrogen ball mills has been achieved. The reactive synthesis process and the hydrogen desorption behaviors of the composite hydrides were investigated by X-ray diffraction (XRD), thermogravimetric and differential scanning calorimetry (TG-DSC). The results show that nano-sized MgH2 and Mg(AlH4)2 could be directly synthesized by pure Mg and pretreated Al powder, as well as Mg-Li-Al alloy powder. Alloying element Li could remarkably promote the synthesis of magnesium alanate, the product composite hydrides releasing 6.2wt% H2 through multi-step decompositions, of which the starting endothermic peaks are as low as 65°C.

Abstract: During the continuous casting process, physical properties of slab for continuous casting at high temperature have an important effect on the slab quality in different part and the curve establishment of external target temperature for slab. It has significance to simulate and investigate the physical behaviors of slab at high temperature during the continuous casting process. Investigation existent in this field is scarce around the world. Continuous casting process is a complicated cooling process in unsteady state that sometimes the external temperature of slab will rise. In allusion to temperature rise and temperature drop, the paper simulated and investigated the physical properties of slab AH36 at high temperature under conditions of different temperatures and different temperature variation velocities, such as thermal expansion property, differential thermal analysis curve (DSC), isobaric thermal capacity (CP) and so on. Results of the investigation have provided a scientific data base for a further study on continuous casting technology and quality control for steel AH36.