Alloys with adhesive mode of scale spallation MRef

4 Alloys with adhesive mode of scale spallation MRef, +C  

3 Macro-photographs of three model alloys (20 x 10 x 1 mm in size) after discontinuous air oxidation till breakaway at 1200°C  

4 SEM of etched cross-section of alloy MRef in as-received condition illustrating formation of Cr carbides at the alloy grain boundaries. 

5 SEM of etched cross-section of alloy -rC after 3100 h discontinuous oxidation at 1200°C showing chromium carbide formation in the metal (a) and crack propagating along scale/metal interface (b). 

6 SEM images of chemically etched alloy +C after 20 h annealing at 1200°C in air (a) furnace cooled (b) air cooled (c) liquid nitrogen quenched. 

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