Electrodeposition of Metal into Pores of Ceramic Materials and Their Mechanical and Electrical Properties.

本文报道了一种在室温下通过电沉积方法将金属离子注入陶瓷材料的孔隙中制备金属/陶瓷复合材料的工艺。新工艺的特点概括如下：（1）金属/陶瓷复合材料的最终微观结构取决于陶瓷材料的初始孔结构，（2）溶解在水溶液或非水溶液中的金属离子在低温下电化学沉淀在陶瓷材料的孔中，导致不控制加工气氛和不限制金属熔点的可能性，（3）在金属/陶瓷的界面处没有反应或几乎没有反应，（5）一旦电化学反应开始，沉积的金属本身就充当跟随电极，表明金属在陶瓷材料的开放空间中的连续电化学沉积。基于AB 关于我们 在此基础上，用多孔氧化铝压块和镍溶液进行了基础实验，在硝酸镍/尿素/乙二醇/硫酸铵的水溶液中，用直流、脉冲和锥形电流（110- 300 mA），通过Ni^<2+>离子的电化学反应，将镍渗透到理论密度为37-62%的多孔氧化铝压块中。沉积的Ni的重量与t<0.22-0.64>（t：沉积时间）成比例。镍的沉积速率是较高的直流电流比脉冲或锥形电流，并为一个较高的孔隙率氧化铝压块。脉冲或锥形电流的使用似乎抑制了Ni的枝晶生长，这在多孔氧化铝中用直流电观察到。复合材料的维氏硬度从17.5GPa的镍/氧化铝区域（样品外部）增加到21.5GPa的内部氧化铝基体中，具有93-94%的理论密度，表明形成了功能梯度复合材料。复合材料的位移与应力呈非线性关系，表明脆性陶瓷的力学性能得到了改善。复合材料的电性能正在研究中。少

We report a processing for preparation of metal/ceramic composites by electrical deposition of metal ions into pores of ceramic material at room temperature. The feature of the new processing is to be summarized as follows ; (1) The final microstructure of metal/ceramic composite depends upon a starting pore structure of ceramic material, (2) The metal ions dissolved in an aqueous or a nonaqueous solution are electrochemically precipitated in the pores of ceramic material at a low temprature, leading to possibilities of no control of processing atmosphere and no restriction of a melting point of metal, (3) No or little reaction at the interfaces of metal/ceramics, (4) the fraction of metal in the composite is controlled by the electric charge passed during the processing, (5) Once the electrochemical reaction starts, the deposited metal itself acts as a following electrode, indicating continuous electrochemical deposition of metal in the open spaces of ceramic material. Based on the ab … More ove concept, a basic experiment was performed with porous alumina compacts and a nickel solution.Nickel was infiltrated into porous alumina compacts of 37-62% of theoretical density by electrochemical reaction of Ni^<2+> ions with direct, pulsed and conical current of 110-300mA in an aqueous solution of nickel nitrate/urea/ethylene glycol/ammonium sulfate. The weight of Ni deposited was in proportion to t^<0.22-0.64> (t : deposition time). The deposition rate of Ni was higher for direct current than for pulsed or conical current, and for a higher-porosity alumina compact. Use of pulsed or conical current seemed to suppress the dendritic growth of Ni which was observed in a porous alumina with direct current. The Vickers hardness of composites with 93-94% of theoretical density increased from 17.5GPa in the nickel/alumina region (outside of sample) to 21.5GPa in the inside alumina matrix, indicating formation of a functionally gradient composite. The composite showed a non- linear relation between displacement and stress, indicating the improvement of mechanical properties associated with brittle ceramics. The electrical properties of composite is under investigation. Less