Surface treatment and corrosion behaviour of Fe–32Mn–6Si shape memory alloy

Electrochemical characterization and corrosion behavior of an Fe‐Mn‐Si shape memory alloy in simulated concrete pore solutions

“…The increasing corrosion resistance with strain up to 4% may be related to the martensitic phase transformation. As stated in previous works , the ϵ‐martensite exhibits a better corrosion performance than the γ‐austenite. When further increasing the strain to 6%, the deformation mechanism of the SMA probably switches to the dislocation induced irreversible plasticity, which can decrease the corrosion resistance by emerging dislocations and the formation of other micro‐defects in the bulk.…”

“…b and c. Considering these results, it seems that the phase transformation is ineffective or has even a detrimental effect on the corrosion resistance. One possible reason is the dual‐phase microstructure consisting of ϵ‐martensite and γ‐austenite, which can be more sensitive against pitting corrosion due to its intrinsic microstructural heterogeneity compared to the microstructure consisting of γ‐austenite only . In this case, both the corrosion current and the pitting potential (i.e., where the current starts to increase sharply by the onset of local corrosion process) tend to decrease with increasing the applied strain, showing that a higher strain level shifts the onset of pitting corrosion to lower potentials.…”

On the Influence of Microstructure on the Corrosion Behavior of Fe–Mn–Al–Ni Shape Memory Alloy in 5.0 wt% NaCl Solution

“…Several studies on the corrosion properties of the Fe-Mn-Si alloy have been conducted. [7][8][9][10][11][12][13][14][15][16][17][18] Although the corrosion resistance of the alloy could be improved through additions of alloying elements such as Cr, Al, Cu, Ni, and N, its commercial application is still limited due to its poor superelastic behavior at room temperature. [19] The Fe-28Ni-17Co-11.5Al-2.5Ta alloy, which was the first iron-based SMA showing a recovery strain up to 13% in a polycrystalline state, [19] shows a corrosion behavior similar to carbon steel in a 3.5 wt% NaCl solution.…”

Modelling of martensitic transformation and plastic slip effects on the thermo-mechanical behaviour of Fe-based shape memory alloys

“…Recently, techniques are proposed in order to improve shape memory effect of these alloys by reducing the grain size with equal channel angular pressing process (Wei et al, 2008) or by the aligning precipitations of second-phase particles realised through ageing after pre-deformation at room temperature (Wen et al, 2007). Corrosion resistance improvement was also proposed by surface treatment (Charfi et al, 2008). By contrast, works dealing on their behaviour modelling, necessary to the optimization of their performances and application design by finite element method, start to emerge with largely one-dimensional formulations (Goliboroda et al, 1999;Lazghab and Wu, 2005).…”