Elastic properties of hot isostatically pressed magnesium diboride

Abstract

Powder of magnesium diboride was hot isostatically pressed using three qualitatively different cycles: cooling under pressure (DMCUP), "standard" cycle with pressure and temperature reduced simultaneously and isothermal presure release. Elastic properties of dense material were measured at normal conditions using resonant ultrasound specroscopy (RUS) method. The highest value of density (2.66 g/cc) and elastic moduli (Young's modulus 273.5 GPa, bulk modulus 143.9 GPa, Poisson's ratio 0.183) correspond to the sample processed using DMCUP cycle. These data agree very well with some theoretical predictions based on quantum mechanics calculations. Effect of lower density on elastic constants is consistent with theoretical approach based on elasticity theory taking into account effect of low porosity.

arXiv comment14 pages, 2 figures, 1 table; data are added for sample prepared with another HIP cycle, larger number of resonances is used for calculation of elastic constants

References in corpus (8)

• Hot isostatic pressing of powder in tube MgB2 wires
• Compressibility and Electronic Structure of MgB2 up to 8 GPa
• Calculated elastic and electronic properties of MgB${}_2$ at high pressures
• The influence of microstructures and crystalline defects on the superconductivity of MgB2
• Microstructure and superconducting properties of hot isostatically pressed MgB2
• Improved superconducting properties of MgB2
• The degradation of MgB2 under ambient environment
• A search for incipient lattice instabilities in MgB${}_2$ by anelastic spectroscopy

Cited by in corpus (1)

• Negative thermal expansion of MgB${}_2$ in the superconducting state and anomalous behavior of the bulk Grüneisen function