激光熔化沉积γ/Mo_2Ni_3Si金属硅化物合金的腐蚀行为  

Corrosion Behavior of Laser Melting-Deposited γ/Mo_2Ni_3Si Metal Silicide Alloy

作　　者：徐亚伟[1] 王华明[1] 

机构地区：[1]北京航空航天大学激光材料加工与制造技术实验室,北京100083

出　　处：《稀有金属材料与工程》2007年第4期660-664,共5页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(50331010);航空基础科学基金(05H51009)

摘　　要：采用极化曲线,塔菲尔图(TafelPlot),交流阻抗(EIS)及浸泡腐蚀技术,研究了激光熔化沉积γ/Mo2Ni3Si合金在不同酸,碱,盐介质中的腐蚀行为。结果表明,该合金在1mol/LNaOH溶液中,由于形成了稳定的钝化膜,耐蚀性优异;在1mol/LH2SO4溶液中,合金只能形成不稳定的钝化膜;而在含Cl-的中性或酸性介质中,合金没有钝化趋势,且由浸泡腐蚀试验表明,在1mol/LHCl溶液中,由于Cl-导致相界腐蚀,合金耐蚀性较差。The corrosion behavior of Laser melting-deposited γ/Mo2Ni3Si alloy consisting of Mo2Ni3Si primary dendrites and Mo2Ni3Si/γ eutectic matrix in different mediums were investigated by polarization curve, Tafel Plot, EIS and immersion corrosion. Results showed that the alloy has excellent corrosion resistance in NaOH solution of 1 mol/L owing to the formation of stable passivation film. Unstable passivation film was formed in H2SO4 solution of 1 mol/L. No passivation occurred in neutral or acid solutions containing Cl^- The alloy exhibited very poor corrosion resistance during the immersion test in HCI solution of 1 mol/L due to the preverential phase-boundary corrosion by Cl^-.

关 键 词：金属硅化物 腐蚀 极化曲线 交流阻抗(EIS) 浸泡腐蚀 

分 类 号：TG135.6[一般工业技术—材料科学与工程] TG172.63[金属学及工艺—合金]