Table 2.
Corrosion properties of carbon nanotube-reinforced magnesium nanocomposites.
| Samples | Reinforcement | Processing Route | Reinforcement Particle Size | Corrosion Medium |
icorr (μA·cm−2) |
Ecorr (V vs. SCE) |
Corrosion Rate (mm/year) | Rp (Ω·cm2) | Ref. | ||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Non Polarized | Polarized | ||||||||||
| Immersion Time (h) | HE or WL |
PDP | |||||||||
| AZ31 (after 1, 24 and 336 h immersion time) |
- | DMD | - | SBF | 94.70 | –1.545 | 1 | 2.176 mm/year |
- | - | [144] |
| - | 44.22 | –1.441 | 24 | 1.016 mm/year |
- | - | |||||
| - | 213.45 | –1.402 | 336 | 4.906 mm/year |
- | - | |||||
| AZ31 (after 1, 24 and 336 h immersion time) |
CNT (1wt.%) | - | 87. 62 | –1.502 | 1 | 2.013 mm/year | - | - | |||
| - | 17.42 | –1.408 | 24 | 0.400 mm/year | - | - | |||||
| - | 9.33 | –1.373 | 336 | 0.214 mm/year | - | - | |||||
| Mg–6Al | CNT (4 wt.%) | MBM + CP + HTE | average diameter: 9.5 nm average length: 1.5 μm |
3.5% NaCl | 5 | –1.55 | - | - | - | - | [92] |
| AZ91 | MWCNTs (1 wt.%) |
MS | - | 3.5% NaCl | - | – | - | 5–9 gm−2day−1 |
- | - | [132] |
| MWCNTs (5 wt.%) |
- | - | – | - | 19–24 gm−2day−1 |
- | - | [132] | |||
| Mg | MWCNTs (0.1 wt.%)-Dispersed during melt stirring process (0 h) |
MS | - | 3.5% NaCl | 98 | –1.618 | - | 4.5 mm/year |
368 | [131] | |
| MWCNTs (0.1 wt.%)- Dispersed during melt stirring process (6 h) |
- | 280 | –1.520 | - | 12.8 mm/year | 332 | |||||
| AZ91 | GNPs (0.5 wt.%) |
SPM | diameter: 5 and 8 nm surface area: 750 m2/g |
3.5 wt.% NaCl | 326.902 μA | –1.449 | - | - | 4.13 mm/year |
- | [145] |
| MWCNT (0.5 wt.%) |
diameter: 8 nm surface area: 250 m2/g | 388.431 μA | –1.491 | - | - | 4.92 mm/year |
- | ||||
| C60 (0.5 wt.%) |
average thickness: 1–2 nm | 212.137 μA | –1.506 | - | - | 2.68 mm/year |
- | ||||
| Mg | CNT (0.3wt.%) | DMD | average diameter: 20 nm and length: less than 100 μm | 3.5 wt.% NaCl | 56 | –1.57 | - | - | - | - | [63] |
| CNT (1.3wt.%) | 572 | –1.50 | - | - | - | - | |||||
| Mg | MWCNTs (0.5 wt.%) |
SPM | - | 3.5 wt.% NaCl | 579.4 μA | –1.544 | - | - | 24.62 mm/year |
- | [89] |
| Mg | MWCNTs (0.5 wt.%) |
SPM + PEO | - | 130.4 μA | –1.401 | - | - | 14.78 mm/year |
- | ||
| Mg-0.5 MWCNT | GNP | SPM + PEO (coating with graphene addition) | - | 101.0 μA | –1.424 | - | - | 14.46 mm/year |
- | ||
CNTs: Carbon nanotubes, MWCNTs: Multi-walled carbon nanotubes, GNPs: Graphene nanoplatelets, Icorr: Corrosion current density, Ecorr: Corrosion potentials, HE: Hydrogen evolution, WL: Weight loss, PDP: Potentio-dynamic polarization, Rp: Polarization resistance, DMD: Disintegrated melt deposition, PM: Powder metallurgy, SPM: Semi powder metallurgy, HTE: Hot extrusion, MBM: Mechanical ball milling, CP: Cold pressing, MS: Melt stirring, SLM: Selective laser melting, PEO: Plasma electrolytic oxidation.