Improving corrosion resistance of additively manufactured WE43 magnesium alloy by high temperature oxidation for biodegradable applications

• DOI: 10.1016/j.jma.2022.08.009
• Publication Date: 2022-09-30T04:57:56Z
• Authors: Jinge Liu; Bangzhao Yin; Fei Song; Bingchuan Liu; Bo Peng; Peng Wen; Yun Tian; Yufeng Zheng; Xiaolin Ma; Caimei Wang
• Keywords: High-Temperature Corrosion; Immersion; Passivation; Weight change

Laser powder bed fusion (L-PBF) has been employed to additively manufacture WE43 magnesium (Mg) alloy biodegradable implants, but L-PBF samples exhibit excessively rapid corrosion. In this work, dense were built with the relativity density reaching 99.9%. High temperature oxidation was performed on in circulating air via various heating temperatures and holding durations. The diffusion at elevated generated a gradient structure composed of an oxide layer surface, transition middle matrix. consisted rare earth (RE) oxides, became thick increasing duration. matrix α-Mg, RE oxides Mg24RE5 precipitates. precipitates almost disappeared layer. Enhanced passivation effect observed treated by suitable high oxidation. original lost 40% weight after 3-day immersion Hank's solution, broke into fragments 7-day immersion. casted solution roughly half 28-day samples, which heated 525 °C for 8 h, kept structural integrity, only 6.88% substantially improved corrosion resistance contributed surface. On one hand, outmost isolated corrosive medium; other considerably inhibited owing lack Overall, provides efficient, economic safe approach inhibit promising prospects future clinical applications.