Hydraulic Fatigue Test
Definition - What does Hydraulic Fatigue Test mean?
Fatigue testing performed on test specimens with a hydraulic test machine is known as a hydraulic fatigue test. A fatigue test is a method that determines the behavior of a material under fluctuating loads. In hydraulic fatigue tests, the hydraulic machines have multiple modes in which materials or components are tested with pulsating or alternating loads having periodic signals or random signals.
Corrosionpedia explains Hydraulic Fatigue Test
Hydraulic fatigue tests are used to easily simulate the quasi-static and dynamic loads acting at multiple locations in the material or components. In hydraulic fatigue tests, the loads on the material or any components can be applied axially in flexure or in torsion. Once the load is applied, depending on the amplitude of the mean and cyclic load, net stress in the specimen may occur in one direction or may reverse direction. The data obtained from a fatigue test is represented as an S-N diagram or an S-N plot, which represents the relationship between the number of cycles required to cause failure in the material versus the amplitude of the cyclic stress. The curves drawn on the S-N diagram represent the constant mean stress. During testing, if the material has lost strength or ductility because of chipping or rusting, then it will break down immediately at the application of a nominal stress.