Fraunhofer Institute for Mechanics of Materials IWM
Fatigue
Load-bearing components and structures in all industrial sectors such as automotive, vehicle, railway, aerospace, steel and bridge constructions are exposed to complex stresses. Many technical cases of damage can be attributed to material fatigue due to cyclic mechanical loading. In order to ensure the reliable use of critical components, the assessment of material fatigue is of decisive importance.
In order to fulfill the requirement for lightweight, resource-efficient and fatigue-resistant components, it is necessary to consider the properties of the component surface layer during the design phase of a construction. On the basis of our material and damage models for components and structures subjected to fatigue loading, we perform reliable service lifetime calculations so our customers are able to fully benefit from the potential of the strength reserves of their construction materials under extreme loads.
#Controlling material fatigue
We:
- determine the static and fatigue strength as well as the safety of components
- support you in material selection and design optimization for cyclic loaded components
- investigate the lightweight potential of load-bearing components and structures thus avoiding over-dimensioning and thereby saving costs for material, production and transport
- support you in the material substitution for existing and new constructions
- help you to improve the endurance limit of metallic components by mechanical surface treatment and to avoid fatigue fractures
- assist you to handle production-related material defects in a safe and reliable way
- advise you with respect to continuation of component operation and the lifetime extension of metallic structures
- support you with numerical welding simulation to determine the residual stress state and the distortion of your components in order to evaluate their lifetime
What we offer#
- Numerical and experimental stress and strain analysis of components under static and cyclic loading
- Numerical component assessment under static and cyclic loading experimentally supported by component tests
- Numerical and experimental strength and safety analysis
- Welding simulation and strength analysis of welded joints under consideration of residual stress and distortion
- Numerical simulation of shot-peening, deep rolling and high frequency mechanical impact and resulting residual compressive stresses in the surface-near layer of metallic structural materials
- Calculation of service lifetime of mechanical surface-treated (such as shot-peened, deep rolled and high frequency mechanical impact) components including the quantification of the lifetime improvement and the estimation of the cost-benefit ratio
- Material qualification
- Vibrations and shock tests and experimental modal analysis
- Microstructure and failure analysis
Contact us! Together we'll find a customized solution for the challenges you face.
#Selection of measurement and equipment highlights
- Electromechanical, servo-hydraulic and resonance testing machines (N to MN) to carry out static and cyclic material and component tests
- Equipment to perform fracture mechanical tests (i.e. ASTM E399, E1820, E1921 and E647) over large force and temperature ranges
- Multi-axial loading devices (tension-torsion; span) for multiaxial component testing
- Air-conditioned shock and vibrations tests
- Metallography and fracture surface analysis