Table 1 Thickness and compositions of the oxide films and modified alloy as obtained with the bilayer model of the native oxide-covered and passivated MPEA-25Cr5Mo, MPEA-15Cr10Mo, and MPEA-35Cr surfaces.
From: Origin of enhanced passivity of Cr–Fe–Co–Ni–Mo multi-principal element alloy surfaces
Thickness (±0.1 nm) | Cr at. % (±2%) | Fe at.% (±3%) | Co at.% (±3%) | Ni at.% (±2%) | Mo at.% (±2%) | ||
|---|---|---|---|---|---|---|---|
MPEA-25Cr5Mo | |||||||
Native oxide film | Outer layer | 1.1 | 38 | 17 | 4 | 26 | 15 |
Inner layer | 0.3 | 100 | – | – | – | – | |
Modified alloy | – | 14 | 19 | 5 | 58 | 4 | |
Passive oxide film | Outer layer | 1.2 | 48 | 16 | 3 | 13 | 20 |
Inner layer | 0.6 | 100 | – | – | – | – | |
Modified alloy | – | 14 | 20 | 5 | 57 | 4 | |
Bulk alloy | – | 25 | 25 | 5 | 40 | 5 | |
MPEA-15Cr10Mo | |||||||
Native oxide film | Outer layer | 1.3 | 17 | 13 | 3 | 46 | 21 |
Inner layer | 0.2 | 100 | – | – | – | – | |
Modified alloy | 8 | 7 | 4 | 73 | 8 | ||
Passive oxide film | Outer layer | 1.8 | 45 | 6 | 2 | 16 | 31 |
Inner layer | 0.3 | 100 | – | – | – | – | |
Modified alloy | – | 9 | 8 | 4 | 69 | 10 | |
Bulk alloy | – | 15 | 10 | 5 | 60 | 10 | |
MPEA-35Cr | |||||||
Native oxide film | Outer layer | 1.4 | 65 | 19 | 4 | 12 | – |
Inner layer | 0.7 | 100 | – | – | – | – | |
Modified alloy | – | 13 | 14 | 6 | 67 | – | |
Passive oxide film | Outer layer | 1.3 | 74 | 12 | 4 | 10 | – |
Inner layer | 0.5 | 100 | – | – | – | – | |
Modified alloy | – | 19 | 16 | 6 | 59 | – | |
Bulk alloy | – | 35 | 20 | 5 | 40 | – | |
