Abstract In the present work, microwave energy was used for casting Al 7039 alloy at 2.45 GHz in the ambient cavity environment. Effects of input power and insulation of the mould assembly during irradiation on charge melting and mould preheating were studied. Five different casts were produced at 1000 W, 1200 W, 1400 W, 1400 W with an insulated pouring basin and 1400 W with insulated mould assembly. Melting time of the charge was the least while using 1400 W with insulated mould assembly, whereas preheating of the mould was observed minimum during casting at 1400 W inside an insulated pouring basin. Cast microstructures revealed that less preheating of the mould resulted in finer grains and intermetallics, which improve tensile properties of the cast. Fractographic analyses showed the presence of coarse intermetallics in the casts produced with insulated mould assembly, which resulted in significant reduction of tensile properties.

中文翻译：

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微波功率和绝缘对2.45 GHz铸造Al 7039合金显微组织和拉伸性能的影响

摘要 在目前的工作中，微波能量用于在 2.45 GHz 的周围腔环境中铸造 Al 7039 合金。研究了辐照过程中模具组件的输入功率和绝缘对炉料熔化和模具预热的影响。生产了五种不同的铸件，功率为 1000 W、1200 W、1400 W、1400 W，带有绝缘浇注盆，1400 W 带有绝缘模具组件。使用 1400 W 和绝缘模具组件时，装料的熔化时间最短，而在绝缘浇注盆内以 1400 W 铸造期间，观察到模具预热最短。铸件微观结构表明，模具预热较少会产生更细的晶粒和金属间化合物，从而提高铸件的拉伸性能。