Fatiguetest

Fatiguetest refers to a testing procedure aimed at evaluating fatigue life, the number of cycles a material, component, or assembly can endure under repetitive loading before failure. The term is commonly used in engineering, materials science, and product development to characterize durability and reliability.

In mechanical fatigue testing, specimens are prepared and mounted in a test rig and subjected to cyclic loads that may be axial, torsional, bending, or multiaxial. Tests can be force-controlled or strain-controlled and are performed at various temperatures or in corrosive environments to simulate service conditions. The primary outcome is the number of cycles to crack initiation or to final failure.

Data from fatiguetests are analyzed to produce fatigue-life relationships, such as stress–life (S-N) curves or strain-life (epsilon-N) curves. Basquin's law and Coffin-Merlin relations may be used to model high- and low-cycle regimes. Results guide design limits, safety factors, and maintenance planning.

Applications include automotive components, aircraft structures, structural steel, and electronics housings. Standards such as ASTM E466 (for force-controlled axial fatigue tests) and related methods provide testing protocols, reporting requirements, and specimen preparation guidelines.

The term can also denote fatigue testing in human factors research, where selective cognitive and physiological assessments measure fatigue effects on performance due to sleep loss, workload, or illness. In both uses, fatiguetests aim to quantify endurance and predict performance under repeated or sustained load.