Fatigue

Introduction to Fatigue (why does material respect SN ?)

Difference between Fatigue and Creep

CTD presentation - March'26
VE presentation (more detailed) - March'26

Definition and notations

Basics about Fatigue tests

List of Fatigue data available, SSP

Upload Fatigue data (systematically linked to material center)

• Core Labs Capabilities

Electro-mechanical machines are generally used for static tests, as they provide better control over applied force or displacement. For polymers, these machines can also be used for mid-range fatigue tests; note that at Alpharetta, only a contact strain gauge is available for strain acquisition.

The film folding tester at Bollate is designed to evaluate the lifespan of films, but it is limited to film materials only and can only test thicknesses between 250 and 350 microns.

• Corporate Capabilities

Servo-hydraulic machines are well-suited for fatigue testing, with a dynamic testing range equipped with larger load cells. Strain measurements can be performed using Digital Image Correlation (DIC), or with contact / non-contact extensometers.

At the Brussels site, in-house developed demonstrator parts and testing setups enable us to conduct fatigue bending tests on L-shaped samples with various radii and on demonstrator parts with or without ribs and weld lines.

Contacts: Michel Houba, Dominique Delcourt

• ADL Capabilities

Although tooth bending is not a classic fatigue test, this can be used to validate the FE models, with capacity to test higher frequencies.

_{Tips: The current FE model for fiber filled polymers, can be applied only if the failure mode is slow crack growth controlled failure or brittle failure, which typically occurs at the root of the teeth in gear tooth bending.} 

Contacts: Matilde Scurria, Lorenzo Mancin

• Potential external partners

Syensqo has engaged Leartiker to generate fatigue test data (including hysteresis measurements), to support the creation of Digimat fatigue cards across different temperatures. Other capabilities include sample molding, creep analysis, advanced...