Part Of The Nuclear Material System Correlation Study

As the energy crisis for traditional fossil fuel further expands, nuclear energy is regarded as one of the important new energy which will solve this crisis, due to its efficiency, security and clean. Among the large number of nuclear fuels, the new LEU U-Mo/Al dispersion fuel has caught the close attention of the international RERTR project because of its excellent performance. However, the nuclear reactor can not work stably without the protection of nuclear structure materials. Many research indicates that the Zr-based alloys have the priority.Following the international research focus, combining the literature experimental data, phase relations of part of nuclear material systems U-Mo-Al, Zr-Ni-Al ternary systems have been studied via CALPHAD approach as well as experimental investigation. Reasonable isothermal sections have been obtained. Content is as follows:1. After investigating the phase diagram and thermodynamic data in previous literatures, U-Mo binary system has been optimized by CALPHAD approach, using PARROT module in Thermo-Calc software. Liquid and terminal solutions are modeled as substitutional solution, the intermetallic compound MoU2 is treated as stoichemistric phase and (j)LMo,UΦ=Aj+BJT+CJTlnT+DjT2+EJT-1 is adopted for the parameters of BCC_A2 phase. A good agreement has been reached between experimental data and present calculation.2. Integrating the thermodynamic parameters of U-Mo, Al-Mo and U-Al(with minor modification) binary systems, U-Mo-Al ternary system has been extrapolated and optimized. Three isothermal sections and one liquidus projection have been calculated and the interfacial reaction result in U-Mo/Al diffusion couple has been reasonably expressed according to the present work.3. The 1123K isothermal section of Zr-Ni-Al ternary system has been experimentally determined via alloy quenching method and material analysis detection means, eg. SEM, EDS, XRD etc. The phase relations including 15 three-phase region and 5 tie lines of two-phase region.