No abstract

No abstract

The design and performance evaluation of a novel high temperature fatigue device simultaneously driven by servo motor and piezoelectric actuator is our focus. The device integrates monotonic and cyclic loading functions with a maximum tensile load of 1800 N, driving frequency of 50 Hz, alternating load of 95 N, and maximum service temperature of 1200 °C. Multimodal fatigue tests with arbitrary combinations of static and dynamic loads are achieved. At temperatures that range from RT to 1100 °C, the tensile and tensile-fatigue coupling mechanical behaviors of UM Co50 alloys are investigated to verify the feasibility of the device.

No abstract

A miniature piezoelectric-driven fatigue device with three degrees of freedom is developed. The device integrates two fatigue testing functions, including uniaxial tensile fatigue and tensile-bending combined loading modes. The synchronous tensile-bending loading principle is described, which is applicable for calculating the vector displacements along two orthogonal directions and investigating the anisotropic fatigue properties. Regarding the combined loading mode, maximum load/displacement amplitudes for tensile and bending vector components that could be achieved are 16.9 N/22.8 µm and 3.3 N/5.6 µm, respectively. Based on tensile and tensile-bending combined fatigue loading modes, the displacement responses and fatigue lives at loading frequencies ranging from 1 Hz to 100 Hz are valuated experimentally to indicate the validation.