Residual stress determination in oxidized bulk metallic glass using X-ray diffraction and FIB/DIC methods

The presence of residual stresses inside the engineering components generated by local inelastic deformation can influence material’s performance considerably during mechanical loading. Surface engineering of ZrCuAl-based bulk metallic glasses (BMGs) by low-temperature (

In the current study stresses introduced as a consequence of ZrO2 (Al2O3) formation on thermochemically oxidized (Zr55Cu30Al10Ni5)98Er2 BMG were investigated. For this purpose, conventional X-ray diffraction sin2ψ and incremental core-ring focused ion beam (FIB) milling methods have been utilized. The BMG was initially oxidized in the controlled gaseous atmospheres imposing an extremely high pO2 at 600 K for 60 hr.

The residual stress sin2ψ analysis was conducted on (011) reflection of the tetragonal-ZrO2 peak where it reveals the existence of compressive stress in ZrO2. Surface strain relief monitored in high-resolution SEM imaging of a deposited stochastic pattern during gradual milling and measured by digital image correlation (DIC) also indicated the occurrence of compressive residual stresses in the surface region of the oxidized BMG.