Study on Anodizing at Constant Current for Sealing Treatment of Nano-diamond Powder

Abstract

································································································································································································································Abstract In this study, an aluminum oxide layer for sealing treatment of nano-diamond powder was synthesized by anodizing under constant current. The produced pore size and oxide thickness were investigated using scanning electron microscopy. The pore size increased as the treatment time increased, current density increased, sulfuric acid concentration decreased, which is different from the results under constant voltage, due to a dissolution of the oxide layers. The oxide layer thickness by the anodizing increased as temperature, time, and current density increased. The results of this study can be applied to optimize the sealing treatment process of nano-diamond particles of 4-10 nm to enhance the resistances of corrosion and wear of the matrix.

Study on Improvement of Corrosion Resistance and Wear Resistance by Anodizing and Sealing Treatment with Nano-diamond Powder on aluminum

“…그림을 보면 온도가 증가함에 따라 기공크기가 증 가한다. 다공질 피막의 생성과 성장기구에 관하여 Keller 등은 화학적으로 산화피막을 용해할 수 있 는 전해액에서 양극산화처리를 하면 우선 Barrier 피막이 빠르게 형성된 후 산화피막 층에 국부적으 로 전류밀도가 높은 곳에서 열이 발생하여 이 Joule 열에 의한 단순한 화학적 용해작용으로 산화피막이 용해되어 기공이 생성되며, 일단 기공이 생성되면 그곳은 전류밀도가 더욱 높아져서 열의 발생이 더 많아지게 되고 따라서 기공은 표면의 수직방향으로 계속 성장하게 된다고 설명하였다8,12,13) . 실험결과로 부터 기공의 크기는 전해액의 온도가 높을수록 증…”