Atlas Journal of Materials Science 2018-01-20T02:43:55-05:00 Abdelmajid Kassem Open Journal Systems <p>Atlas Journal of Materials Science is an open access, peer-reviewed international journal that publishes original research articles, short communications, and review articles in all fields of Atlas Journal of Materials Science.</p> Challenges to Fabricate Large Size-Controllable Submicron-Structured Anodic-Aluminum-Oxide Film 2018-01-20T02:43:55-05:00 Jin Shyong Lin Shih Hsun Chen Ker Jer Huang Chien Wan Hun Chien Chon Chen <p>Anodic aluminum oxide (AAO) is well known for its unique controllable structure and functional contributions in research and developments. However, before AAO can be widely used in the industry, some engineering problems should be overcome. In this study, we designed a novel electrochemical mold, which can resolve the exothermal problem for large-size aluminum sheets during high-voltage anodization process. AAO film with a large sample size of 11 x 11 cm2 in area, 148 μm in thickness and 450 nm in average pore diameter, decorated with ordered-pattern structure, was successfully obtained through a 200 V anodization process. It was noticed that the local heat was generated with increasing the anodizing voltage, resulting in undesired pits and burr defects on the AAO surface. In order to retain AAO’s quality and reduce the producing cost of the anodization process, a mass producing system combining with an overhead conveyor was proposed. The convenient anodization system, novel electrochemical mold and bath may help to fabricate high-quality AAO films efficiently.</p> 2017-06-14T01:36:21-04:00 ##submission.copyrightStatement## Impedance Studies of Thermochemically Activated 316L Stainless Steel 2018-01-20T02:43:55-05:00 Wen Ching Say Chen Chang Chan Jin Shyong Lin Chien Chon Chen Alex Fang Shih Hsun Chen <p>This study proposed a novel thermochemical activation (TCA) method to modify the surface of 316L stainless steel (SS). At the first stage, phosphate ions were introduced to 316L SS surface by a heat-diffusion process. After rapid quenching into calcium citrate solution, calcium and hydroxide ions were sealed in the TCA compound layer. The TCA and original 316L SS were immersed in Hanks’ solution to evaluate their biocompatibility. Electrochemical impedance spectroscopy analysis showed that the surface active compound layer affected the TCA 316L SS, and its total impedances of Bode and Nyquist plots were higher than that of the original ones during immersed in Hank’s from 1 to 14 days. After TCA treatment, the corrosion resistance increased greatly, and thus reducing the release of ions from stainless steel, such as Fe, Cr, Ni and Mo. In the Ca- and P-rich areas, the ions were guided to deposit in the Hanks’ solution, forming bone-like hydroxyl apatite. The treatment has been proven to reduce the ionic release from 316L SS, which is considered to be a great improvement for implanted alloys.</p> 2017-06-14T01:45:10-04:00 ##submission.copyrightStatement##