Until now, the durability of plastic components has been extremely difficult to assess, considering the variety of influencing factors. This is particularly important for critical safety components, whose failure involves a significant danger potential and subsequent liability risks.
At the "JEC" trade show held from 1 to 4 April in Paris, at its stand U74, hall 1.3, Fraunhofer LBF will present solutions for simulating the service life of components made from plastic and other composite materials.
The number and usage of components made from plastic and composite materials has been growing steadily throughout the last few years. Until now, reliable, material-specific testing methods and rating concepts for these plastic components, enabling an assessment of their expected service life, have not been available. Within the framework of a Wing Project of the German Federal Ministry for Education and Research lead by Robert Bosch GmbH, engineers are currently working on new material technologies. Research scientists at the Fraunhofer Institute for Durability and System Reliability LBF in Darmstadt are developing a simulation method which will enable the reliable assessment of fatigue and ageing of plastic components under various ambient influences. Using specimens made from thermoplastic materials and resembling the actual components, researchers have investigated the behaviour of the materials in laboratory tests, as a function of material, geometry, manufacturing process and various environmental factors (such as temperature, fuel, or oil). These parameters are critical to strength, load-carrying capability and service life of the materials.
The effect of these combined parameters on material fatigue can subsequently be shown in a numerical simulation of the components. "First of all we analyse the vibratory strength of plastic specimens immersed in an oil bath, by introducing cyclic loads", explains Andreas Büter, Head of Department at Fraunhofer LBF. "Depending on the load at which specimen fatigue or fracture occurs, the fatigue strength, i.e. the relationship between the cyclic load applied and the maximum permitted number of vibrations can be calculated." On the basis of the results obtained, a diagram called Wöhler curve is determined by the engineers, which enables a statistical assessment of the fatigue life of a component.
How a fuel rail, for example, will withstand engine vibrations under simultaneous contact with fuel, is simulated on the basis of the results obtained by means of a numerical model of the component. "We calculate the stress and strain occurring in the material at various loads", explains Büter. "We know from experiments the stresses the material can withstand without damage, and at which strains damage occurs. Hence we can assess the service life of plastic components with maximum reliability".
The purpose of the simulation models, which are adapted to the specific material in hand, is to enable designers to take into account ageing processes and the effects of various ambient factors on plastic components at an early stage in the development phase - similar to metal components. This will reduce the cost and time involved in design modifications and adaptation of shape.
Anke Zeidler-Finsel | Fraunhofer Gesellschaft
NRL develops laser processing method to increase efficiency of optoelectronic devices
16.04.2019 | Naval Research Laboratory
Hollow structures in 3D
29.03.2019 | Albert-Ludwigs-Universität Freiburg im Breisgau
A stellar flare 10 times more powerful than anything seen on our sun has burst from an ultracool star almost the same size as Jupiter
A localization phenomenon boosts the accuracy of solving quantum many-body problems with quantum computers which are otherwise challenging for conventional computers. This brings such digital quantum simulation within reach on quantum devices available today.
Quantum computers promise to solve certain computational problems exponentially faster than any classical machine. “A particularly promising application is the...
The technology could revolutionize how information travels through data centers and artificial intelligence networks
Engineers at the University of California, Berkeley have built a new photonic switch that can control the direction of light passing through optical fibers...
Physicists observe how electron-hole pairs drift apart at ultrafast speed, but still remain strongly bound.
Modern electronics relies on ultrafast charge motion on ever shorter length scales. Physicists from Regensburg and Gothenburg have now succeeded in resolving a...
Engineers create novel optical devices, including a moth eye-inspired omnidirectional microwave antenna
A team of engineers at Tufts University has developed a series of 3D printed metamaterials with unique microwave or optical properties that go beyond what is...
17.04.2019 | Event News
15.04.2019 | Event News
09.04.2019 | Event News
18.04.2019 | Life Sciences
18.04.2019 | Physics and Astronomy
18.04.2019 | Life Sciences