引力波探测计划为观测宇宙提供了全新而有效的途径， 有助于揭示宇宙的基本运作规律。 本文探究了Au-Pt 合金作为空间引力波探测的关键组件———“检验质量”的生产工艺，弥补了 Au-Pt 合金铸造凝固过程多尺度相关研究成果的匮乏。 宏观有限元计算结果表明，在充型初期合金熔体形成强烈对流，后逐渐趋于平稳在模具内形成环流。在凝固过程中铸件的四周和底部区域呈现出较大的温度梯度，而铸件的中心区域温度梯度小，出现了明显的温度分层现象。 凝固由底部和四周开始向中心区域推进。 在凝固初期，在铸件表面出现一层细晶，凝固向铸件内部推进过程中形成柱状晶区，最终在中心区域形成等轴晶。 探究了不同铸造工艺对铸件质量的影响。 研究发现，随着浇注温度的升高，气隙与压力逐渐减小，缩松现象得到改善。 但当温度提高到一定程度时，其改善效果会变得不明显。 浇注速度的变化直接影响合金熔体的动能与动量，低速时对流不显著产生温度分层现象和晶粒异常粗化现象，而适当提高速度则使组织变得更加均匀致密。 此外，模具的换热系数决定了铸件的凝固时间、组织形貌及晶粒数目。

The gravitational wave detection program provides a new and effective way of observing the universe, which helps to reveal the basic operating laws of the universe. The production process of a Au-Pt alloy, a key component (“test mass”)for space-based gravitational wave detection, was explored, thus compensating for the lack of research results related to the multiscale solidification process of Au-Pt alloy castings. Macroscopic finite element calculations reveal that the alloy melt experiences strong convection at the beginning of filling and then gradually tends to stabilize, resulting in annular flow in the mold. During the solidification process, the temperature gradient around and at the bottom of the casting is large, whereas the temperature gradient in the center of the casting is small, resulting in an obvious temperature stratification phenomenon. The solidification starts from the bottom and the surrounding area to the center area. In the early stage of solidification, a layer of fine crystals appears on the surface of the casting. During the process of the solidification of the casting advancing inward, the columnar crystal area is formed, and finally, equiaxial crystals are formed in the center of the region. The influence of different casting processes on the quality of castings was explored. With increasing pouring temperature, the air gap and pressure gradually decrease, and the shrinkage phenomenon is improved. However, when the temperature is increased to a certain degree, the improvement effect becomes less obvious. The change in pouring speed directly affects the kinetic energy and momentum of the alloy melt. The flow is not obvious when a low speed produces a temperature stratification phenomenon and a grain coarsening phenomenon, whereas an appropriate increase in speed makes the organization more uniform and denser. In addition, the heat transfer coefficient of the mold affects the solidification time, microstructure morphology and number of grains in the sample.