31Si12，采用退火工藝以減少亞穩(wěn)相的含量，并利用電化學阻抗譜和電位動力學極化技術分析了材料在25 ℃、7%（質量分數(shù)）H2SO4溶液中的耐腐蝕性，并進行了等效電路分析。結果表明，退火處理（1050 ℃、4 h）改善了亞穩(wěn)相Ni31Si12的含量和分布，退火后Ni-Si共晶的鈍化性能和耐腐蝕性提升。亞穩(wěn)相的含量越少，耐腐蝕性能越強。;The modified Bridgman directional solidification technique was used to prepare the Ni-Si eutectic composites at solidification rate of 25 μm/s. However, the formation of metastable phase Ni31Si12 was inevitably during solidification process. Annealing treatment was conducted to reduce the number of metastable phases. Electrochemical impedance spectroscopy and potentiodynamic polarization techniques were used to analyze the corrosion resistance of Ni-Si eutectic composites in the 7wt% H2SO4 solution at 25 °C. The equivalent circuit was analyzed. Results show that the passivation performance and corrosion resistance behavior of Ni-Si eutectic composites are improved after annealing at 1050 °C for 4 h, which is mainly attributed to improvement of content and distribution of metastable phase Ni31Si12. The less the content of metastable phase, the stronger the corrosion resistance."/>