As an ideal layout scheme for launch vehicle, bearing co-bulkhead tank can improve the slenderness ratio of launch vehicle, reduce structure weight and increase structure efficiency. In this paper, a novel cryogenic tank co-bulkhead was fabricated by vacuum assisted resin transfer molding (VARTM) process. Consisting of LD10 alloy and polymethacrylimide (PMI) foam-sandwich, the new cryogenic tank co-bulkhead was designed with variable-thickness, hemi-ellipsoid structure, thermal insulation and bearing function. Fundamental temperature distribution, thermal stress and low-temperature load sensitivity of the foam-sandwich co-bulkhead were also assessed by finite element analysis and environment tests in simulated service environment. The results showed that the analog values highly agreed with the test results, and thermal insulation and bearing function of the foam-sandwich co-bulkhead could satisfy the design requirement, which proved the reliability of bonding quality and feasibility of the bonding technique.

To improve the preparation technology and mechanical properties of carbon/carbon composites, a kind of Zirconium dioxide modified Carbon/carbon (C/C–ZrO2) composites were prepared by Sol-Gel Process combined with isothermal chemical vapor infiltration (ICVI) method. This method could shorten preparation cycle greatly to reduce the cost. The microstructures and mechanical properties of the C/C–ZrO2 composites were investigated. The results indicate that the ZrO2 modified phase is uniformly distributed in the carbon matrix, the bending strength and modulus of C/C–ZrO2 composites are much higher than unmodified C/C composites due to its particle toughening and fiber toughening.