Anticorrosion behavior of ultrafine-grained Al-26 wt% Si alloy fabricated by ECAP

作者：Jiang, Jinghua^*; Ma, Aibin; Song, Dan; Yang, Donghui; Shi, Jun; Wang, Kaile; Zhang, Liuyan; Chen, Jianqing

来源：Journal of Materials Science, 2012, 47(22): 7744-7750.

DOI：10.1007/s10853-012-6703-9

• PURE TI
• MECHANICAL-PROPERTIES
• CORROSION BEHAVIOR
• CHANNEL
• REFINEMENT
• STRENGTH
• COPPER

Ultrafine-grained (UFG) Al-26 wt% Si alloy was obtained through multipass equal-channel angular pressing (EACP) procedure and subsequently tested in 3.5 wt% NaCl solution for the evaluation of electrochemical corrosion. The results show that the ECAPed alloy with increased number of pressing passes obtain lower mass-loss ratios, nobler E (corr) and E (pit), lower I (corr) values, and higher anode polarization. The improved corrosion resistance of the ECAPed alloy results from the homogeneous UFG structure with the breakage of brittle large primary silicon crystals, which contributes to a higher pitting resistance. The oxidation product with improved adhesion force and protection efficacy can be formed with greater ease on UFG alloys. It implies that grain refinement through severe-plastic-deformation can enhance anticorrosion behavior of hypereutectic Al-Si alloys, besides the well-known strengthening and toughening effects.

• 出版日期2012-11
• 单位河海大学