亚稳相对定向凝固Ni-Si共晶腐蚀行为的影响  

Effect of Metastable Phase on Corrosion Behavior of Directionally Solidified Ni-Si Eutectic Composites

作　　者：崔春娟[1,4] 刘薇 邓力[1] 王松苑 苏海军 芦禹[3] Cui Chunjuan;Liu Wei;Deng Li;Wang Songyuan;Su Haijun;Lu Yu(School of Metallurgical Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,China;State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi'an 710072,China;School of Metallurgy and Materials,University of Birmingham,Edgbaston B152TT,UK;Shaanxi Engineering Research Center of Metallurgical,Xi'an 710055,China)

机构地区：[1]西安建筑科技大学冶金工程学院,陕西西安710055 [2]西北工业大学凝固技术国家重点实验室,陕西西安710072 [3]伯明翰大学冶金与材料学院,英国埃德巴斯顿B152TT [4]陕西省冶金工程技术研究中心,陕西西安710055

出　　处：《稀有金属材料与工程》2021年第9期3110-3115,共6页Rare Metal Materials and Engineering

基　　金：National Natural Science Foundation of China (51201121);Science and Technology Foundation for Selected Overseas Chinese Scholars of Shaanxi Province (2015);Key Industry Innovation Chain (Group) Project of Shaanxi Province (2019ZDLGY 04-04)

摘　　要：采用改进的Bridgman定向凝固技术制备了凝固速率为25μm/s的Ni-Si共晶复合材料。由于在凝固过程中不可避免地会产生亚稳相Ni31Si12,采用退火工艺以减少亚稳相的含量,并利用电化学阻抗谱和电位动力学极化技术分析了材料在25℃、7%(质量分数)H_(2)SO_(4)溶液中的耐腐蚀性,并进行了等效电路分析。结果表明,退火处理(1050℃、4 h)改善了亚稳相Ni_(31)Si_(12)的含量和分布,退火后Ni-Si共晶的钝化性能和耐腐蚀性提升。亚稳相的含量越少,耐腐蚀性能越强。The modified Bridgman directional solidification technique was used to prepare the Ni-Si eutectic composites at solidification rate of 25μm/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%H_(2)SO_(4) solution at 25℃.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℃ for 4 h,which is mainly attributed to improvement of content and distribution of metastable phase Ni_(31)Si_(12).The less the content of metastable phase,the stronger the corrosion resistance.

关 键 词：Bridgman定向凝固 Ni-Si共晶复合材料 亚稳相 腐蚀行为 电化学 

分 类 号：TB33[一般工业技术—材料科学与工程]