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For the sake of enhance the sinter ability and electrical conductivity of BaZr0.1Ce0.7Y0.2O3‐δ (BZCY) electrolytes, a modified aqueous gel‐casting method was applied to synthesize high sintering active and high conductive BZCY nano‐powders. The new approach makes it easy to obtain pure perovskite. The highly sintering active purity‐phase of BZCY nano‐powder (particle size of 50∼100 nm) was obtained by calcining at 1100°C for 2 h. Nano‐powders effectively reduce the sintering densification temperature and successfully prepare BZCY electrolyte with relative density > 96 % at 1450°C, and promote grain growth with an average grain size of 2.36 μm. Benefiting from this, improved electrical conductivities (e.g., 12.4×10−3 S cm−1 at 700°C, in wet air) are obtained. The NiO‐BZCY/BZCY/LSCF‐BZCY anode‐supporting single cell shows a peak power density of 0.75 W cm−2 at 700°C while taking ambient air as oxidants and wet H2 (∼3 vol.% H2O) as fuels. [ABSTRACT FROM AUTHOR]

Aluminum alloy is widely used in automobile parts because of its light weight and good process performance. In view of the complex structure of aluminum alloy automobile rear upper control arms, multiple forming processes and the difficulty in quality control, in this paper, we propose a rolling-forging composite process to produce a rear upper control arm. Based on the reasonable volume distribution of the blank by cross-wedge rolling, multi-step forging was carried out. Finite element simulation of thermomechanically coupled multi-step forming was carried out using DEFORM software. Based on a comparison of the traditional process and the proposed rolling-forging composite forming process, we concluded that the rolling-forging composite process can greatly reduce the material cost and the forming force, resulting in superior product performance. The coarse-grain structure of products at different process temperatures was analyzed by a crystal-phase experiment. The results show that the process temperature of the multi-step process, as well as the heat treatment temperature and time have an important influence on the coarse-grain structure of the product. The optimal preheating temperatures for preforging and final forging dies were determined to be 335 °C and 350 °C, respectively; a preheating temperature of 530 °C and a solution time of 45 min resulted in the least coarse-grain surface structure. The research results provide a theoretical basis for improving the multi-step forming quality of automobile rear upper control arms. [ABSTRACT FROM AUTHOR]