Abstract Dielectric properties of Huimin siderite ore were investigated by using the self-made high-temperature cavity perturbation method from room temperature to approximately 1000 °C at 2.45 GHz. The dielectric properties of the siderite ore remain constant from room temperature to 400 °C, then there is a rapid increase in both the dielectric loss factor and loss tangent from 400 °C to 600 °C, due to the decomposition during microwave roasting of siderite. Dielectric loss factor of siderite plays a leading role in the microwave heating process. Siderite has a maximum penetration depth at 400 °C and then gradually decreases with increasing temperature. According to dielectric properties of siderite, the maximum microwave absorption is achievable at the appropriate penetration depth. The temperature of siderite can be increased to 1000 °C in 10 min, showing that microwave heating is fast and saving time compared to conventional heating methods. The heating rate reaches a maximum at about 7 min, and decreases with microwave heating time, in accordance with the dielectric properties of the siderite.

中文翻译：

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惠民菱铁矿介电特性及微波加热特性

摘要 采用自制高温腔微扰法研究了惠民菱铁矿在室温至约1000 °C、2.45 GHz频率范围内的介电特性。由于菱铁矿在微波焙烧过程中发生分解，菱铁矿的介电性能从室温到 400 °C 保持不变，然后从 400 °C 到 600 °C 介电损耗因子和损耗角正切均迅速增加. 菱铁矿的介电损耗因子在微波加热过程中起主导作用。菱铁矿在 400 °C 时具有最大穿透深度，然后随着温度的升高逐渐减小。根据菱铁矿的介电特性，在适当的穿透深度下可以实现最大的微波吸收。菱铁矿的温度可在 10 分钟内升至 1000°C，表明与传统加热方法相比，微波加热速度快且节省时间。根据菱铁矿的介电特性，加热速率在约 7 分钟时达到最大值，并随着微波加热时间的延长而降低。