新型层状化合物Ti_2AlC在酸性溶液中的腐蚀行为  

Corrosion Behavior of Layered Ternary Carbide Ti_2AlC in Acidic Solution

作　　者：王敬平[1] 梅炳初[1] 周卫兵[1] 王苹[1] 杨淑霞[1] 

机构地区：[1]武汉理工大学材料复合新技术国家重点实验室,武汉430070

出　　处：《无机材料学报》2009年第2期402-406,共5页Journal of Inorganic Materials

基　　金：国家自然科学基金(20771088);教育部博士点基金(20050497002)

摘　　要：热压烧结得到高纯致密的Ti2AlC块体.将Ti2AlC在浓的和稀的HNO3、HCl及H2SO4溶液中浸泡,得到试样的腐蚀速率及腐蚀类型.电化学方法测量试样在三种稀溶液中的腐蚀电位和腐蚀电流及动电位极化曲线.浸泡腐蚀实验发现,Ti2AlC在酸中的腐蚀类型由点腐蚀发展到晶间腐蚀最后为剥蚀,腐蚀速率随着浸泡时间的延长而不断增大.其中在浓HNO3中腐蚀速率最大,稀HCl的腐蚀速率最小.除H2SO4外,Ti2AlC在浓酸溶液中的腐蚀率均大于其稀溶液.电化学实验表明,在稀HNO3中自腐蚀电流最小,自腐蚀电位最大.稀H2SO4自腐蚀电流最大.在三种稀溶液中均出现钝化,其中稀H2SO4维钝区间最宽.High-purity, fully dense Ti2AlC samples were synthesized by hot pressing process. Their corrosion rate and corrosion type after immersed in concentrated and dilute HNO3, HCl and H2SO4 were obtained. The corrosion potential, corrosion current and potentiodynamic polarization curves were measured by electrochemical methods. Corrosion process is pitting at first, then intergranular corrosion, while exfoliation at last. The corrosion rate increases with time. The corrosion rate reaches the biggest in concentrated HNO3 while reaches the slowest in dilute HCl. The corrosion rate in the concentrated solution is faster than that in dilute solution, except in H2SO4. Electrochemical test shows the corrosion current reaches the biggest in the dilute H2SO4 and reaches the smallest in dilute HNO3. Ti2AlC shows passive behavior in all acid solution, and the passivation interval is the widest in dilute H2SO4.

关 键 词：TI2ALC 点腐蚀 晶间腐蚀 剥蚀 极化曲线 

分 类 号：TF125[冶金工程—粉末冶金] TB304[冶金工程—冶金物理化学]