Elastic properties of hot isostatically pressed magnesium diboride

TL;DR

This study investigates the elastic properties of magnesium diboride processed by hot isostatic pressing, revealing how different cycles affect density and elastic moduli, with results aligning well with theoretical predictions.

Contribution

It provides experimental measurements of elastic properties of magnesium diboride processed by various hot isostatic cycles, and compares results with theoretical models.

Findings

DMCUP cycle yields highest density and elastic moduli.

Elastic properties agree with quantum mechanical predictions.

Lower density samples show consistent elastic behavior with elasticity theory.

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.