Nanocrystalline intermetallic compounds in the Ni–Al–Cr system synthesized by mechanical alloying and their thermodynamic analysis

Synthesis and characterisation of nanostructured Al–Al3V and Al–(Al3V–Al2O3) composites by powder metallurgy

“…Adding reinforcement particles improves the strength mainly by the load transfer from the matrix to the reinforcement due to the differences in the elastic constants [45]. In general, factors increasing the strength of Al composites and alloys can be classified into four groups: (1) Hall–Petch strengthening due to grain boundaries, (2) Orowan hardening caused by hard particles, (3) solid solution hardening resulting from the presence of solute atoms in Al lattice and (4) precipitation hardening due to coherent or semi-coherent precipitates [17]. In the case of this study, the two first mechanisms can be cited as strength mechanisms.…”

“…This method results in a uniform distribution of the reinforcement particles without the segregation commonly found in cast composites [11–14]. MA has been successfully applied for the synthesis of nanocrystalline materials, such as intermetallics and composites [15–18]. MA is a promising technique to synthesise a variety of equilibrium and non-equilibrium alloy phases starting from blended elemental or pre-alloyed materials, including metals, ceramics, polymers and composites.…”

Characterization and thermodynamic study of nanostructured Cu‐26Zn‐4Al (wt.%) shape memory alloy through mechanical alloying

“…Increasing mechanical alloying to 30 hours leads to gradual disappearance of intensity of the diffraction peaks attributed to zinc and aluminum. The temperature increases with large numbers of crystalline defects throughout mechanical alloying owing to high collisions between milling equipment which supports solid solution formation as a result of simplicity in diffusion of solute atoms into matrix [7]. Moreover, according to diffraction peaks of 40 hours, a single phase with face centered cubic (ffc) structure and the lattice parameter close to that copper lattice parameter is formed.…”

“…Since the development of Miedema's semi empirical model during 1970s and early 1980s, which has been proposed by Miedema and his colleagues, prediction of formation enthalpies for amorphous phase, crys-49 50 talline solid solution and crystalline intermetallic in binary systems was found to be reliable based on achieved agreements between improved model and experimental results [3][4][5]. Moreover, because this model in its original form, is merely applicable for binary systems, the extended version of Miedema's semi-empirical model which is practical for multicomponent systems has been proposed [1,2,[6][7][8]. Additionally, Miedema model is favored in virtue of its simplicity in calculation [9][10][11].…”

Effect of Heating Rate on the Microstructure and Mechanical Properties of Spark Plasma Sintered CNTs Reinforced Nickel Aluminide

“…Intermetallic compounds are special materials that comprises of two or more metals or non-metals with different structural features which occurs as solid compounds, among these intermetallic are NiAl, TiAl and NiAl3 [1]. Nickel aluminides have shown tremendous potential for industrial applications especially in high temperature structural materials in aerospace applications e.g., compressor and turbine blades, also in automobile as piston rings and valves of combustion engines [2].…”