The experiments of preparation of Al Si alloys by electrothermal process were carried out respectively in 20 kW, 100 kW and 1 800 kW DC arc furnaces. The mechanism of furnace bottom rise was studied. It was found that...The experiments of preparation of Al Si alloys by electrothermal process were carried out respectively in 20 kW, 100 kW and 1 800 kW DC arc furnaces. The mechanism of furnace bottom rise was studied. It was found that the bottom rise can be divided into three types, including the low bottom temperature, abnormal reducing reaction and carbide deposition. The furnace bottom rise is related to the carbon ratio of the briquet, the heating speed of the briquet and the parameters and operation of furnace.展开更多
Composites are most promising materials of recent interest. Metal matrix composites (MMCs) possess significantly improved properties compared to unreinforced alloys. There has been an increasing interest in composites...Composites are most promising materials of recent interest. Metal matrix composites (MMCs) possess significantly improved properties compared to unreinforced alloys. There has been an increasing interest in composites containing low density and low cost reinforcements. In view of the generation of large quantities of solid waste by products like fly ash and slags, the present expensive manner in which it is discarded, new methods for treating and using these solid wastes are required. Hence, composites with fly ash and granulated blast furnace (GBF) slag as reinforcements are likely to overcome the cost barrier for wide spread applications in automotive and small engine applications. In the present investigation, AA 2024 alloy-5 wt% fly ash and GBF slag composites separately were made by stir casting route. Phase identification and structural characterization were carried out on fly ash and GBF slag by X-ray diffraction studies. Scanning electron microscopy with energy dispersive X-ray spectroscopy EDS was used for microstructure analysis. The hardness and compression tests were carried out on all these alloy and composites. The SEM studies reveal that there was a uniform distribution of fly ash and GBF slag particles in the matrix phase and also very good bonding existed between the matrix and reinforcement. Improved hardness and mechanical properties were observed for both the composites compared to alloy;this increase is higher for Al-fly ash composite than Al-GBF slag composite.展开更多
文摘The experiments of preparation of Al Si alloys by electrothermal process were carried out respectively in 20 kW, 100 kW and 1 800 kW DC arc furnaces. The mechanism of furnace bottom rise was studied. It was found that the bottom rise can be divided into three types, including the low bottom temperature, abnormal reducing reaction and carbide deposition. The furnace bottom rise is related to the carbon ratio of the briquet, the heating speed of the briquet and the parameters and operation of furnace.
文摘Composites are most promising materials of recent interest. Metal matrix composites (MMCs) possess significantly improved properties compared to unreinforced alloys. There has been an increasing interest in composites containing low density and low cost reinforcements. In view of the generation of large quantities of solid waste by products like fly ash and slags, the present expensive manner in which it is discarded, new methods for treating and using these solid wastes are required. Hence, composites with fly ash and granulated blast furnace (GBF) slag as reinforcements are likely to overcome the cost barrier for wide spread applications in automotive and small engine applications. In the present investigation, AA 2024 alloy-5 wt% fly ash and GBF slag composites separately were made by stir casting route. Phase identification and structural characterization were carried out on fly ash and GBF slag by X-ray diffraction studies. Scanning electron microscopy with energy dispersive X-ray spectroscopy EDS was used for microstructure analysis. The hardness and compression tests were carried out on all these alloy and composites. The SEM studies reveal that there was a uniform distribution of fly ash and GBF slag particles in the matrix phase and also very good bonding existed between the matrix and reinforcement. Improved hardness and mechanical properties were observed for both the composites compared to alloy;this increase is higher for Al-fly ash composite than Al-GBF slag composite.
