A sintered lunar regolith is expected to be used to construct buildings, roads, and landing pads for spacecrafts on the Moon. Here, we demonstrate that focused microwave heating is effective for the rapid solidification of the lunar regolith simulant to obtain regolith gravel without any microwave susceptor. The conventional multimode microwave oven cannot heat lunar regolith simulants and requires microwave susceptors such as silicon carbide (SiC) and thermal insulators because of its low dielectric loss. We achieved rapid microwave heating of a lunar regolith simulant without using a susceptor or thermal insulator by forming an intense microwave electric field using a cavity resonator and a semiconductor microwave oscillator. Focused microwaves at 2.45 GHz produced the gravel-shaped and solidified lunar regolith at 300 °C lower temperature than a conventional electrical furnace, where more than 1050 °C temperature was required to sinter the lunar regolith simulant. In addition, we produced larger gravel of the lunar regolith simulant using 915 MHz. The intense electric field generated by the single-mode resonator promoted the solidification of the lunar regolith simulant without any additional substances. This process enables the local production of structured lunar regoliths on the Moon without the transport of any materials from the Earth.

中文翻译：

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通过超快速微波烧结在月球上自给自足地生产月球风化层砾石

烧结的月球风化层预计将用于建造建筑物、道路和月球航天器的着陆场。在这里，我们证明聚焦微波加热对于月球风化层模拟物的快速凝固是有效的，无需任何微波感受器即可获得风化层砾石。传统的多模式微波炉无法加热月球风化层模拟物，并且由于介电损耗低，因此需要碳化硅（SiC）等微波感受器和绝热体。我们通过使用空腔谐振器和半导体微波振荡器形成强微波电场，在不使用基座或绝热体的情况下实现了对月球风化层模拟物的快速微波加热。 2.45 GHz 的聚焦微波在比传统电炉低 300 °C 的温度下产生了砾石状固化的月球风化层，而传统电炉需要超过 1050 °C 的温度来烧结月球风化层模拟物。此外，我们还使用 915 MHz 生产了较大的月球风化层模拟物砾石。单模谐振器产生的强电场促进了月球风化层模拟物的凝固，无需任何额外物质。这一过程使得能够在月球上本地生产结构化的月球风化层，而无需从地球运输任何材料。