ELECTROLYTIC PRODUCTION OF Fe-Ni ALLOY FILM FOR TENSION/TORQUE SENSOR UTILZING MAGNETOSTRICTION EFFECT

为了研制磁致伸缩张力/扭矩传感器，采用电解法制备了Fe-Ni合金薄膜。研究结果如下：（1）在硫酸盐、氨基磺酸盐和氯化物镀液中电沉积Fe-Ni合金，获得了所需成分的合金膜。合金的电沉积行为属于反常类型，即低贵金属Fe优先于Ni被电还原。(2)测定了合金镀液和单一金属镀液中Fe和Ni的偏极化曲线。这种异常共沉积是由于Fe的存在抑制了Ni的沉积而加速了Fe的沉积。(3)解释这种异常共沉积现象的最合理的假说是与水溶液性质有关的氢氧化物抑制机制。然后将溶剂从水变为甲醇。Fe-Ni合金在甲醇溶液中的电沉积行为也表现出反常的类型。因此，氢氧化物抑制机理不一定适用于Fe-Ni系。(4)为了改善合金的表面形貌，在电解液中加入硼酸，在较宽的电解条件下获得了光亮膜。(5)用振动样品磁强计研究了电沉积Fe-Ni合金的磁性能。Ni含量为80%（质量分数）的合金膜矫顽力小于5 Oe，具有实用价值。

Fe-Ni alloy films were produced electrolytically for the development of tension/torque sensor utilizing magnetostriction effect. The results obtained are as follows ;(1) Fe-Ni alloys were electrodeposited from sulfate, sulfamate and chloride baths to obtain the alloy film with a desired composition. The electrodeposition behavior of the alloys were found to be classified into the anomalous type in which less noble Fe were electroreduced in preference to Ni.(2) The partial polarization curves of Fe and Ni were measured in the alloy planting and the single metal plating baths. The anomalous codeposition was caused by the suppression of Ni deposition in the presence of Fe but by the acceleration of Fe deposition.(3) The most plausible hypothesis explaining for the anomalous codeposition is called hydroxide suppression mechanism involved with properties of aqueous solution. Then the solvent was changed from water to methanol. The electrodeposition behavior of Fe-Ni alloys from methanol baths also showed the anomalous type. Then, the hydroxide suppression mechanism is not necessarily applicable to Fe-Ni system.(4) In order to improve the surface appearance of the alloy, boric acid was added to baths and lustrous films was obtained over a wide range of electrolysis conditions.(5) The magnetic properties of the electrodeposited Fe-Ni alloys were investigated using VSM. The alloy films with 80 mass % Ni showed lower coercive force than 5 Oe and were available in practical use.