Laser melting of extraplanetary rocks under lunar conditions

拟议项目的总体目标是确定重力减小和真空对行星外岩石粉末激光熔化的影响，作为空间资源利用（ISRU）在其他天体上建设基础设施的基础。重点是利用月球风化层，因为月球目前是国际航天飞行的主要目标，目前没有在月球条件下进行激光熔化的充分科学依据。激光粉末床融合（LPBF）的风化层有潜力大幅降低成本和运输需求的未来空间任务。爱因斯坦电梯的研究仪器为研究月球重力下的激光熔化风化层提供了必要的基础设施。在每天4秒（8小时）的失重状态下，最多可以进行100次实验，这在国际上是独一无二的。月球表面的大气状况可以用真空来充分近似。该项目将生产模拟风化层，并对其化学和矿物组成进行分析。粒子性质及其与热输入过程的相互作用将通过实验和模拟进行研究。因此，应确定在考虑到热耗散和重力减少的情况下，月球条件如何影响月球岩石的熔化行为。此外，还将研究风化层组成的自然变化对融化行为的影响。因此，该项目将使用实验方法和模拟来显示与地面条件相比，在重力和真空减少的情况下可以产生哪些材料特性。导出的模型将允许对熔体产品的性能进行预测。

The overall objective of the proposed project is to determine the influence of reduced gravity and vacuum on laser melting of extraplanetary rock powder as a basis for building infrastructure by In-Space Resource Utilization (ISRU) on other celestial bodies. The focus is on the use of lunar regolith, since the moon is currently a major target of international spaceflight and there is currently no adequate scientific basis for laser melting under lunar conditions.Laser Powder Bed Fusion (LPBF) of regolith has the potential to drastically reduce the costs and transport requirements of future space missions. The research instrument of the Einstein Elevator provides the necessary infrastructure to study laser melting of regolith under lunar gravity. Up to 100 experiments can be performed at 4 seconds of weightlessness per day (8 hours), which makes this research device unique in the international arena. The atmospheric conditions on the moon's surface can be sufficiently approximated by a vacuum.For the project, regolith simulants will be produced and their chemical and mineralogical composition will be analyzed. The particle properties and their interaction with the process in terms of thermal input will be investigated experimentally and simulatively. Thus, it shall be determined how lunar conditions influence the melting behaviour of lunar rocks under consideration of the reduced heat dissipation and gravitation. In addition, the influence of natural variations in the composition of the regolith on the melting behaviour will be investigated. The project will thus use experimental methods and simulation to show which material properties can be produced under reduced gravity and vacuum compared to terrestrial conditions. A derived model will allow the prediction of the properties of the melt products.