Rapid Evaluation for Aging of Aluminum Alloys by Chronoamperometry

近年来，由于汽车、飞机等车辆经常在高速行驶的情况下使用，人们对提高强度重量比的材料进行了研究。因此对铝合金也提出了高强度的要求。它的强度是由于老化而实现的。然后我在三年前开始了这项关于铝合金老化的电化学评价的研究。本研究采用循环伏安法、计时安法和计时电位法作为电化学技术。在1995年至1997年这三年中，取得了以下五点成果：采用循环伏安法、时电流法和时电位法对航空用铝锌镁合金的时效进行了研究。对汽车活塞用多组分铝合金、Al-Si-Cu-Ni-Mg合金的时效进行了电化学研究。探讨了时间电位测定法和时间电流测定法的可能性。将前一种方法应用于Al-Mg合金的时效测定。各种电化学技术，如计时电流法也被应用于sus316钢的敏化以及SUS304钢的敏化。各种电化学技术也被应用于沥青和聚丙烯腈纤维碳碳复合材料的石墨化。这些结果表明，计时安培法、计时电势法和循环伏安法等电化学技术可用于评价各种金属材料在加热诱导下的转变。

Recently, materials for automobiles, aircraft etc. are investigated for the improvement of strength to weight ratio, since the vehicles are often used in the situation of high speed. Therefore, the high strength is also required for aluminum alloys. Its strength is realized due to aging. Then I started this study where electrochemical evaluation for aging of aluminum alloys three years ago. In this study, cyclic voltammetry, chronoamperometry and chronopotentiometry were utilized as electrochemical technique for the purpose. In these three years between 1995 and 1997, the following five points were obtained :1. The aging of Al-Zn-Mg alloys utilized for aircraft was investigated, using cyclic voltammetry, chronoamperometry and chronopotetiometry.2. The aging of Multicomponent aluminum alloys, Al-Si-Cu-Ni-Mg alloys utilized for automobile pistons was investigated electrochemically.3. The possibility of chronopotentiometry as well as that of chronoamperometry was investigated. The former technique was applied to the mesaurement of aging for Al-Mg alloys.4. Various ekectrochemical techniques like chronoamperometry were also applied to the sensitization of SUS 316 steels as well as that of SUS304 steels.5. Various electrochemical techniques were also applied to the graphitization of carbon-carbon composites based on Pitch and PAN fibers.All of these results indicate that various electrochemical techniques like chronoamperometry, chronopotentiometry and cyclic voltammetry can be applied to evaluate for the transformation of various metallic materials induced by heating.