Advanced solidification studies on transparent alloy systems: A new european solidification insert for Material Science Glovebox on board the International Space Station

International audienceInvestigations on solidifying transparent model alloys have served frequently to gain knowledge on physical phenomena occurring during solidification of metallic alloys. However, quantitative results were only possible to obtain in thin samples where convection can successfully be suppressed. Quantitative studies on three dimensional phenomena not being affected by natural convection are thus only possible under microgravity conditions. Therefore, the European Space Agency (ESA) is planning to launch a new insert for the Material Science Glovebox (MSG) on board of the International Space Station (ISS) for studies on solidification phenomena in thick samples. Four different classes of transparent model alloys will be used to address the following scientific topics: (i) Columnar to Equiaxed Transition in Solidification Processing, (ii)Novel Peritectic Structures and In-Situ Composites; (iii) Solidification alongan Eutectic Path in Binary Alloys; and (iv) Solidification along an Eutectic Path in Ternary Alloys. Here, we give details on the scientific objectives and the operational features ESA's new solidification device will offer

Advanced solidification studies on transparent alloy systems: A new european solidification insert for Material Science Glovebox on board the International Space Station

International audienceInvestigations on solidifying transparent model alloys have served frequently to gain knowledge on physical phenomena occurring during solidification of metallic alloys. However, quantitative results were obtainable in thin samples where convection can successfully be suppressed. Quantitative studies on three-dimensional phenomena not being affected by natural convection are thus only possible under microgravity conditions. Therefore, the European Space Agency (ESA) is planning to launch a new insert for the material science glovebox on board of the International Space Station for studies on solidification phenomena in thick samples. Four different classes of transparent model alloys will be used to address the following scientific topics: (I) columnar to equiaxed transition in solidification processing, (II) novel peritectic structures and in situ composites; (III) solidification along an eutectic path in binary alloys; and (IV) solidification along an eutectic path in ternary alloys. In this article, we give details on the scientific objectives and the operational features ESA's new solidification device will offer

Microgravity studies of solidification patterns in model transparent alloys onboard the International Space Station

We review recent in situ solidification experiments using nonfaceted model transparent alloys in science-in-microgravity facilities onboard the International Space Station (ISS), namely the Transparent Alloys (TA) apparatus and the Directional Solidification Insert of the DEvice for the study of Critical Liquids and Crystallization (DECLIC-DSI). These directional-solidification devices use innovative optical videomicroscopy imaging techniques to observe the spatiotemporal dynamics of solidification patterns in real time in large samples. In contrast to laboratory conditions on ground, microgravity guarantees the absence or a reduction of convective motion in the liquid, thus ensuring a purely diffusion-controlled growth of the crystalline solid(s). This makes it possible to perform a direct theoretical analysis of the formation process of solidification microstructures with comparisons to quantitative numerical simulations. Important questions that concern multiphase growth patterns in eutectic and peritectic alloys on the one hand and single-phased, cellular and dendritic structures on the other hand have been addressed, and unprecedented results have been obtained. Complex self-organizing phenomena during steady-state and transient coupled growth in eutectics and peritectics, interfacial-anisotropy effects in cellular arrays, and promising insights into the columnar-to-equiaxed transition are highlighted