Indentation plasticity of amorphous and partially crystallized metallic glasses

Plastic behavior at room temperature of amorphous, partially crystallized, and fully crystallized Zr41.25Ti13.75Cu12.5Ni10Be22.5 Vitreloy 1 samples was investigated using instrumented indentation. Residual imprints were imaged using atomic force microscopy (AFM). Young's modulus and hardness were estimated using the contact area derived from AFM imaging. It has been shown that the postmortem area measurement is useful to take into account the pileup effect. Indentation experiments performed with a conical tip were associated with parametric two-dimensional axisymmetric finite element modeling using a pressure-sensitive yield criterion. A two-parameter reverse analysis algorithm was used to probe both yield stress and pressure angle. Results showed that the amorphous alloy exhibits a yield stress and pressure angle in good agreement with literature and compressive tests, and that crystallization affects the pressure angle.