Formation of (B2+D0&lt;SUB&gt;3&lt;/SUB&gt;) Two-Phase Microstructure in a Fe-23 Al-7 Ti Alloy

Su, Chien Wei; Chao, Chuen−Guang; Liu, Tzeng-Feng

doi:10.2320/matertrans.mer2007133

Cited by 3 publications

(2 citation statements)

References 17 publications

(36 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…All alloys showed fine-scaled coherent A2 + L2 1 (D0 3 ) microstructures at RT. 24,38,39 According to these TEM observations, the crystallographic orientation relationship of the coherent phases A2 and L2 1 is (002) A2 jj(002) L21 In order to study changes in phase content with temperature, the alloys have been investigated by DTA (Fig. 4).…”

Section: Resultsmentioning

confidence: 99%

Characterization of microstructures, mechanical properties, and oxidation behavior of coherent A2 + L2₁Fe-Al-Ti

2009

View full text Add to dashboard Cite

Two Fe-Al-Ti alloys with coherent aFe,Al (A2) + Fe 2 AlTi (L2 1 ) microstructures have been produced and the evolution of the microstructure with aging time has been studied by light optical and scanning electron microscopy and hardness measurements. The compressive flow strength, creep properties, brittle-to-ductile-transition temperatures (BDTT), and oxidation behavior of the alloys have been evaluated. The results show that the investigated alloys show good flow strength, high creep resistance, and good oxidation resistance. However, their BDDT is high compared to binary Fe-Al-based alloys and compared to other Fe-Al-Ti alloys no increase in creep resistance was achieved by generating coherent microstructures. The latter effect is due to the breakup of the coherent microstructures when the temperature varies because the compositions and consequently the volume fractions of the phases vary markedly depending on temperature.

show abstract

Section: Resultsmentioning

confidence: 99%

Characterization of microstructures, mechanical properties, and oxidation behavior of coherent A2 + L2₁Fe-Al-Ti

2009

View full text Add to dashboard Cite

show abstract

“…The details of the structure of phases is known to depend sensitively on the thermo-mechanical sample history, see, e.g., Refs. [64][65][66][67]. Considering the equilibrium phase diagrams for different temperatures published in Refs.…”

Section: Nano-scale Dynamical Mechanical Analysis Of Fe-al-ti Phasesmentioning

confidence: 99%

Elasticity of Phases in Fe-Al-Ti Superalloys: Impact of Atomic Order and Anti-Phase Boundaries

et al. 2019

View full text Add to dashboard Cite

We combine theoretical and experimental tools to study elastic properties of Fe-Al-Ti superalloys. Focusing on samples with chemical composition Fe71Al22Ti7, we use transmission electron microscopy (TEM) to detect their two-phase superalloy nano-structure (consisting of cuboids embedded into a matrix). The chemical composition of both phases, Fe66.2Al23.3Ti10.5 for cuboids and Fe81Al19 (with about 1% or less of Ti) for the matrix, was determined from an Energy-Dispersive X-ray Spectroscopy (EDS) analysis. The phase of cuboids is found to be a rather strongly off-stoichiometric (Fe-rich and Ti-poor) variant of Heusler Fe2TiAl intermetallic compound with the L21 structure. The phase of the matrix is a solid solution of Al atoms in a ferromagnetic body-centered cubic (bcc) Fe. Quantum-mechanical calculations were employed to obtain an insight into elastic properties of the two phases. Three distributions of chemical species were simulated for the phase of cuboids (A2, B2 and L21) in order to determine a sublattice preference of the excess Fe atoms. The lowest formation energy was obtained when the excess Fe atoms form a solid solution with the Ti atoms at the Ti-sublattice within the Heusler L21 phase (L21 variant). Similarly, three configurations of Al atoms in the phase of the matrix with different level of order (A2, B2 and D03) were simulated. The computed formation energy is the lowest when all the 1st and 2nd nearest-neighbor Al-Al pairs are eliminated (the D03 variant). Next, the elastic tensors of all phases were calculated. The maximum Young’s modulus is found to increase with increasing chemical order. Further we simulated an anti-phase boundary (APB) in the L21 phase of cuboids and observed an elastic softening (as another effect of the APB, we also predict a significant increase of the total magnetic moment by 140% when compared with the APB-free material). Finally, to validate these predicted trends, a nano-scale dynamical mechanical analysis (nanoDMA) was used to probe elasticity of phases. Consistent with the prediction, the cuboids were found stiffer.

show abstract

Laser additive manufacturing of iron aluminides strengthened by ordering, borides or coherent Heusler phase

et al. 2017

View full text Add to dashboard Cite

Formation of (B2+D0<SUB>3</SUB>) Two-Phase Microstructure in a Fe-23 Al-7 Ti Alloy

Cited by 3 publications

References 17 publications

Characterization of microstructures, mechanical properties, and oxidation behavior of coherent A2 + L2₁Fe-Al-Ti

Characterization of microstructures, mechanical properties, and oxidation behavior of coherent A2 + L2₁Fe-Al-Ti

Elasticity of Phases in Fe-Al-Ti Superalloys: Impact of Atomic Order and Anti-Phase Boundaries

Laser additive manufacturing of iron aluminides strengthened by ordering, borides or coherent Heusler phase

Contact Info

Product

Resources

About

Formation of (B2+D0<SUB>3</SUB>) Two-Phase Microstructure in a Fe-23 Al-7 Ti Alloy

Cited by 3 publications

References 17 publications

Characterization of microstructures, mechanical properties, and oxidation behavior of coherent A2 + L21Fe-Al-Ti

Characterization of microstructures, mechanical properties, and oxidation behavior of coherent A2 + L21Fe-Al-Ti

Elasticity of Phases in Fe-Al-Ti Superalloys: Impact of Atomic Order and Anti-Phase Boundaries

Laser additive manufacturing of iron aluminides strengthened by ordering, borides or coherent Heusler phase

Contact Info

Product

Resources

About

Characterization of microstructures, mechanical properties, and oxidation behavior of coherent A2 + L2₁Fe-Al-Ti

Characterization of microstructures, mechanical properties, and oxidation behavior of coherent A2 + L2₁Fe-Al-Ti