TiB_(2)含量对TiB_(2(p))/ZL205复合材料组织和耐蚀性的影响  

Microstructure and Corrosion Resistance of TiB_(2(p))/ZL205 Composites with Different TiB Contents

作　　者：张瑞英[1,2] 李金轩 杨森 闫晗[1] 刘欢 赵鸽 Zhang Ruiying;Li Jinxuan;Yang Sen;Yan Han;Liu Huan;Zhao Ge(School of materials and Engineering,Inner Mongolia University of Technology,Hohhot 010051,China;Inner Mongolia Key Laboratory of Light Metal Materials,Hohhot 010051,China)

机构地区：[1]内蒙古工业大学材料科学与工程学院,内蒙古呼和浩特010051 [2]内蒙古轻合金重点实验室,内蒙古呼和浩特010051

出　　处：《稀有金属》2021年第2期194-202,共9页Chinese Journal of Rare Metals

基　　金：内蒙古自然科学基金项目(2017MS(LH)0509);内蒙古自治区高等学校科学技术研究基金项目(NJZY16086)资助。

摘　　要：以混合盐法制备不同TiB_(2)颗粒含量的TiB_(2)(p)/ZL205复合材料(其中TiB_(2)颗粒含量为2%,4%,6%,质量分数),通过热分析、扫描电镜(SEM)、电位极化测量和电化学阻抗谱测量等方法研究TiB_(2)含量对复合材料组织和耐蚀性的影响。结果表明:随着TiB_(2)颗粒含量的增多,复合材料凝固速度变慢,θ相析出量减少且析出温度由547.71℃降低到531.87℃。在铸态下,随着TiB_(2)颗粒含量增加,团聚物的数量和尺寸变大,晶间腐蚀和点蚀数量增加,自腐蚀电流密度(icorr)值提高,对电化学阻抗谱进行拟合,发现钝化膜电阻(Rf)以及电荷转移电阻(Rct)之和(Rf+Rct)逐渐减小,复合材料耐蚀性逐渐降低;经T6热处理后,复合材料中析出相的数量明显减少,且分布变得更加弥散,且随着TiB_(2)颗粒含量的增加,大尺寸颗粒团聚物内部变得更加弥散,复合材料耐蚀性逐渐降低。相比于相同颗粒含量铸态下的试样,T6热处理后晶间腐蚀和点蚀的数量相对减少,icorr值提高但幅度较小,(Rf+Rct)值明显提高,说明经T6热处理后复合材料耐蚀性有所提高。Particle-reinforced aluminum-based composite materials were gradually used in various major fields due to their high specific strength,high specific stiffness,low thermal expansion coefficient,and good thermal stability.While particle reinforcement improved the mechanical properties of aluminum alloys,people often ignored the impact of particles and their segregation on the corrosion resistance of aluminum alloys.Thermal analysis combined with scanning electron microscopy(SEM)and electrochemical measurements were used to investigate the effect of TiB_(2)particle content on the solidification process of TiB_(2(p))/ZL205 composites and the corrosion resistance of composites in the as-cast and T6 states.The TiB_(2(p))/ZL205 composite material with different TiB_(2)particle contents prepared by mixed salt method(TiB_(2)content of 2%,4%,6%,mass fraction).Remelting was performed in a resistance furnace at 750℃.for 1.5 h.The temperature acquisition deviced DAQ-Central was used to record the temperature change data of the composite material during the solidification process,the recording frequency was to collect 100 temperature data points per second,and then used Origin8.5 to fit the collected temperature data.The influence of TiB_(2)particle content on the solidification process of composite materials was studied.Taking half of the samples for T6 heat treatment,and put the as-cast and T6 samples into 3.5%NaCl aqueous solution to soak for 60 d.The morphology of the structure was observed by SEM,and the Zahner-IM6 e electrochemical workstation was used to perform potential polarization measurement,the sweep voltage range was-150~150 mV,the sweep rate was 1 mV·s^(-1).The electrochemical impedance spectroscopy measurement was carried out at the same time,the sweep frequency range was 100 kHz~100 MHz,swept from high frequency to low frequency,the signal amplitude was 10 mV,and Origin8.5 was used to fit the experimental data.The thermal analysis curve showed that the solidification speed of the composite material became s

关 键 词：TiB_(2)/ZL205复合材料 TiB_(2)颗粒 耐蚀性 极化曲线 

分 类 号：TG174.22[金属学及工艺—金属表面处理]