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Due to its negligible solubility, it is difficult to obtain a W-30Cu composite with a homogenous microstructure. However, with a selected W skeleton, a homogeneous phase distribution was achieved for a W-30Cu composite in the present study. By detailed characterization of the mechanical performance and microstructure of the W-30Cu composite, as well as the stress distribution state under a loading condition, the effects of microstructure homogeneity on the mechanical properties and failure mechanisms are identified. The mechanisms by which the ductility and strength depend on microstructure homogeneity contain the effects on plastic deformation and stress coordination of the Cu phase network. The dominant factors for the high ductility and strength of W-30Cu composites are proposed.

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In the present study the supersonic flow over rigid parachute models is studied by numerically solving the three-dimensional compressible Navier-Stokes equations at a free stream Mach number of 2. The parachute system employed here consists of a capsule and a canopy. Two models are considered: model A and model B. The former is the same model as the experiment, where the canopy is connected with the capsule by a rod, and the whole system is supported by another rod, while the latter does not have these rods. The objective of the present study is to examine the flow field produced by these models, and analyze the effects of aerodynamic interaction such as shock/shock and wake/shock interactions on it. The numerical results show good agreement with the experimental data in the case of model A. In addition, it is found that the difference of flow features between models A and B is rather small. The unsteady flow pulsation phenomenon observed in this study can be demonstrated using three processes; the bow shock formed ahead of the capsule periodically inflates and laterally expands, which is caused by upstream propagation and lateral expansion of the complicated wake/rear shock and fore shock/rear shock interaction systems.

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The inflatable reentry vehicle provides a new technical way in aerospace entry, descent, and landing. The structural failure of inflatable reentry vehicle experiment caused by thermal aeroelastic effect is serious, which needs to be further studied. A traditional numerical method about flexible vehicles separates the aeroheating and aeroelastic problems, resulting in poor matching with the actual test. In this paper, a thermal-fluid-solid coupling model considering inflation gas effect was established, which associates the aeroheating and aeroelastic modules and adopts the LES to improve the depicting ability of hypersonic flow. The model was used to solve the thermal aeroelastic characteristics under extreme aeroheating load. From aeroheating results, the large-scale vortex on windward generated by the interaction of the shock layer and boundary layer has great influence on aeroheating due to the heat dissipation, and the skin deformation also increases the surface friction and local heating near depressions. From aeroelastic analysis, the flexible structure performs violent forced vibration induced by the unsteady large-scale vortex on windward, and the aeroheating effect will significantly increase the thermal stress and natural vibration properties. The thermal-fluid-solid coupling method for the flexible structure proposed in this paper provides a reasonable reference for engineering.

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