Article

Elastic and electronic properties of select M2AX phases

S. E. LoflandDepartment of Physics, Rowan University, Glassboro, New Jersey 08028J. D. HettingerDepartment of Physics, Rowan University, Glassboro, New Jersey 08028K. HarrellDepartment of Physics, Rowan University, Glassboro, New Jersey 08028Peter FinkelDepartment of Physics, Rowan University, Glassboro, New Jersey 08028Surojit GuptaDepartment of Materials Science and Engineering, Drexel University, Philadelphia, Pennsylvania 19104Michel W. BarsoumDepartment of Materials Science and Engineering, Drexel University, Philadelphia, Pennsylvania 19104G. HugLEM, ONERA-CNRS, Châtillon, France

2004en

ABI

Abstract

In this letter we report on the low-temperature specific heat of several M2AX phases: Ti2AlC, V2AlC, V2AsC, Nb2SnC, Ti2AlN, Hf2InC, Nb2AlC, and Cr2AlC. The Debye temperatures are quite high. The density of states at the Fermi level, N(EF) varies from ≈1.4 (eV formula unit)−1 to 6 (eV formula unit)−1. Ab initio calculations show that N(EF) is dictated by the transition metal d–d bands; the A-group element has little effect. We also measured the velocity of sound in V2AlC, V2AsC, Ti2AlC, and Ti2AlN. The average bulk modulus of these materials is over 100 GPa, with a high of ≈140 GPa for Ti2AlN. Our theoretical calculations correctly predict the trend in both the density of states and the bulk modulus, although there is some disagreement in the actual values.

Identifiers

DOI: 10.1063/1.1641177

Citations and references

Cited by 20 references

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