Influence of heat treatment on the corrosion properties of CuAlMn shape memory alloys
| Autor: | Mirko Gojić, Urška Gabor, Stjepan Kožuh, Milan Bizjak, Janez Kovač, Borut Kosec, Ivana Ivanić, Ladislav Vrsalović |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
010302 applied physics
Materials processing Materials science General Chemical Engineering Metallurgy technology industry and agriculture 02 engineering and technology General Chemistry Shape-memory alloy 021001 nanoscience & nanotechnology 01 natural sciences Corrosion 0103 physical sciences corrosion CuAlMn alloy electrochemical methods heat treatment surface analysis General Materials Science 0210 nano-technology |
| Zdroj: | Corrosion Reviews. 37:579-589 |
| ISSN: | 2191-0316 0334-6005 |
| Popis: | This paper reports on the influence of heat treatment on the corrosion properties of CuAlMn alloy in 0.1%, 0.9% and 1.5% NaCl solution (pH = 7.4). Heat treatment of alloy samples was performed by samples annealing at 900°C for 30 min. Electrochemical methods of investigations included measuring the open circuit potential (E oc) and linear and potentiodynamic polarisation. Optical microscopy, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) were used to study the morphology and composition of the corroded surfaces, along with X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Heat-treated samples have slightly more positive values of E oc, slightly lower values of corrosion current density and higher values of polarisation resistance compared with the as-cast alloy. The microscopic analysis showed the rough surfaces due to corrosion processes. Increasing the electrolyte concentration leads to an increase in alloy surface damage. AFM and SEM examinations showed that the surface was covered with interlaced layers of corrosion products, as well as cracks and ducts formed by their dissolution. EDX and XPS analyses showed that corrosive products consist mainly of aluminium and manganese oxides and chlorides. Annealed CuAlMn alloy samples have significantly lower copper content compared with the as-cast CuAlMn alloy. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|