Rotating-beam fatigue properties of Pd40Cu30Ni10P20 bulk glassy alloy

Abstract

High-cycle fatigue strength of a Pd40Cu30Ni10P201) bulk glassy alloy was examined using the rotating-beam fatigue test. The Pd40Cu30Ni10P20 bulk glassy alloy showed a distinct knee at an applied stress of 0.15 σB, (σB: tensile strength of 1600 MPa) and a cycle number N = 4 × 107. However, in the equal applied stress of 0.15 σB, some samples fractured over the knee cycle numbers. It is likely that the origin of the fracture is to the partial embrittled hardening resulting from crystallization or structural relaxation, which is probably caused by the thermal effect from plastic deformation region. Such a partial hardening by the thermal effect characterizes the fatigue feature of the bulk glassy alloy. It is revealed that no fatigue limit is seen on the Wöhler curve of the Pd40Cu30Ni10P20 bulk glassy alloy.