The emergence and disappearance of a high density of microcracks in nitrided Fe-4.65 at.% Al alloy
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Sairamudu Meka
Abstract
Nitriding of recrystallised and cold-rolled Fe-4.65 at.% Al alloy at 550 °C in an ammonia – hydrogen gas mixture of nitriding potential 0.104 atm− 1/2 indicated that nucleation of the thermodynamically (most) stable hexagonal (wurzite) AlN in the ferrite matrix of recrystallised specimen is difficult. The competition between the precipitation of nitrogen gas (dissociation of nitrogen supersaturated ferrite into pure ferrite and nitrogen gas) at the grain boundaries and the precipitation of hexagonal (wurzite) AlN led, via the coalescence of pores filled with nitrogen gas, to the emergence of microcracks along the grain boundaries and the formation of nitride-precipitate free zones near the grain boundaries of the recrystallised specimens. Upon continued nitriding the initially partially nitrided grains became fully nitrided and the microcracks disappeared.
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Articles in the same Issue
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- Hot extrusion of α and α/β-brass alloys
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- The emergence and disappearance of a high density of microcracks in nitrided Fe-4.65 at.% Al alloy
- Notifications
- DGM News
Articles in the same Issue
- Contents
- Contents
- Basic
- On the reaction scheme and liquidus surface in the ternary system Al–Si–Ti
- Experimental study of the phase equilibria of the Ni – Zr system
- Tensile behaviour of micro-sized copper wires studied using a novel fibre tensile module
- Dislocation densities in soft and hard oriented grains of compression deformed textured NiAl polycrystals
- The influence of plastic instabilities on the mechanical properties of a high-manganese austenitic FeMnC steel
- Modeling of isothermal bainite formation based on the nucleation kinetics
- Application of the Kaptay model in calculation of ternary liquid alloys' viscosities
- The influence of the austenite dispersion on phase transformation during the austempering of ductile cast iron having a dual matrix structure
- Effect of trace Ti on the microstructure and mechanical properties of AM50 alloy
- Applied
- Diffusion bonding of the Mo-base alloy TZM with interlayers
- Amorphization, nanocrystallization and magnetic properties of mechanically milled Sm–Co magnetic powders
- Wear behavior of plasma nitrided AISI 420 stainless steel
- Hot extrusion of α and α/β-brass alloys
- Role of surface texture and roughness parameters in friction and transfer layer formation under dry and lubricated sliding conditions
- The emergence and disappearance of a high density of microcracks in nitrided Fe-4.65 at.% Al alloy
- Notifications
- DGM News