Studying fatigue behavior and Poisson's ratio of bulk-metallic glasses

High-cycle fatigue (HCF) experiments were conducted on zirconium (Zr)-based bulk-metallic glasses (BMGs): Zr50Cu40Al10, Zr50Cu30Al10Ni10, Zr41.2Ti13.8Cu12.5Ni10Be22.5, and Zr50Cu37Al10Pd3 (in atomic percent) in air. The fatigue-endurance limit of Zr50Cu37Al10Pd3 was significantly greater than those of Zr50Cu40Al10, Zr50Cu30Al10Ni10, and Zr41.2Ti13.8Cu12.5Ni10Be22.5. The resonant ultrasound spectroscopy technique was employed to determine the Poisson's ratios, shear moduli, and bulk moduli of these BMGs. The ratio of the fatigue-endurance limit to the tensile strength increases with increasing Poisson's ratio. A possible relationship between the ratio of the fatigue-endurance limit to the tensile strength and the ratio of the shear modulus to the bulk modulus or Poisson's ratio will be discussed.