When packages are stacked they will be loaded in compression. Normally paper products have lower compression strength than tensile strength. To enable development of superiour packaging materials it is important to measure accurate comression properties both during static and creep loading.
To be able to characterize in-plane compression properties it is important to prevent buckling of the specimen. This has been taken into account in the testing device developed at RISE. In-plane compression strength can also be measured by the Short Compression Tester (SCT).
The purpose is to determine stress-strain behaviour during in-plane compression.
In packages different deformation and damage mechanisms are activated. In-plane compression is often important, e.g. when boxes are stacked. A good understanding of in-plane compression static and creep properties will help in the development of improved packages.
The in-plane compression apparatus test performs in-plane compressive testing of L=54.6 mm long and w=25 mm wide samples. In the apparatus global buckling is prevented by lateral supports. The apparatus can be used to get the whole stress-strain curves. During the test force is measured, and stress can be calculated; displacement is measured by LVDT gauges, which is used to calculate strain.
The elastic modulus in compression and tension in paper materials are equal. The compression and tensile strengths are however different; the compression strength in compression is much lower than the tensile strength. This is because different damage mechanism is activated.
Stress-strain curves, but also in-plane compression stiffness, strength and energy can be determine. In addition, creep testing can be performed.
In-plane testing of paper
No preparation needed