Scientists at the Fraunhofer Institute have developed a new stress analysis technique which they say can take into account a component’s volume under tension and compression. This could help users decide when compression tests are required during modelling, according to the Institute.

Since most components are subject to multi-axial loadings, a typical design approach is based on material specific modelling and suitable tests to identify the parameters of the model, but these tests can be costly and time consuming, Fraunhofer said.

In engineering tests, while the tensile test has become generally accepted for the identification of material data, tension/compression differences are often neglected, even though construction materials can be stiffer in compression than in tension.

Fraunhofer’s analysis is based on the sum of the normal stresses or the first invariant of the stress tensor. If this sum is less than zero, the corresponding volume of the component is compressed and vice versa. The next step is to compare tensile and compression loaded volumes. If the volume of the component under tension is significantly greater as under compression, the standard models without tension/compression differences can be used for design, avoiding further tests.

This story uses material from Fraunhofer, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.