The coefficient of thermal expansion (CTE) and specific heat capacity of C14-Fe2Ti Laves phase intermetallic compound: an experimental and modeling approach

The present paper reports the findings of an experimental and modeling investigation aimed at determining the coefficient of thermal expansion (CTE) and specific heat capacity ( $${C}_{\text{p}}$$ ) of the Fe2Ti alloy. Arc melting has been employed to prepare the C14-Fe2Ti Laves phase intermetallic compound, and Rietveld refinement of X-ray powder diffraction data were used to ascertain its crystal structure. The homogeneity and composition of the homogenized alloy (1373 K/72 h) have been confirmed by SEM coupled with EDAX experiments. The high-temperature phase stability, CTE, and $${C}_{\text{p}}$$ of the C14-Fe2Ti intermetallic compound were examined through high-temperature X-ray diffraction (HTXRD) and differential scanning calorimetry within the temperature range of 298–1073 K. Rietveld refinement of the HTXRD pattern (from 298 to 1073 K) revealed the average linear and volumetric CTE of the alloy as $${\alpha }_{\text{a}}^{\text{i}}$$ = 0.972 × 10–5, $${\alpha }_{\text{c}}^{\text{i}}$$ = 0.852 × 10–5, and $${\alpha }_{\text{V}}^{\text{i}}$$ = 2.796 × 10–5 K−1, respectively. The measured $${C}_{\text{p}}$$ and enthalpy increment data (HT – H298.15) as a function of temperatures reported in the present investigation are being correlated utilizing the theoretical model applying the quasi-harmonic Debye–Grüneisen model in the temperature range 0–860 K and illustrated different contributions to the total heat capacity, i.e., vibrational, anharmonic, and electronic.