Stress Engineering Services has developed a wide range of test programs and specialized tools to test and characterize the behavior of materials used in many products and packaging. The test data is collected to establish material behaviors and determine which materials are appropriate to use, and when.
This proprietary test machine, developed by Stress Engineering Services, is capable of testing at rates on the order of 10,000% per second, capturing how stress, strain and ductility at failure are affected by high strain rate events, such as drop impact. Very early in the development process this test can be used to screen candidate material for a particular design application, or to develop material models for predicting failure using non-linear finite element analysis methods.
Depending on the required load/displacement, this test machine is capable of cycling a test sample up to 100 hertz. One of the most common applications involves testing of elastomers or other polymers subjected to long term cyclic loading.
Failures in most plastic products occur under multi-axial stress/strain states. The effect of this stress state is to reduce the ductility of the materials, which becomes the limiting load scenario for design. To collect data for this important material parameter we developed a Biaxial Tensile Test system. This equipment captures the behavior of film and thin materials under biaxial tension. It is used to evaluate materials for drop impact applications and other high strain rate events.
A melt flow device measures a polymer’s viscosity at elevated temperature. Melt flow rate is a key specification provided by material manufacturers to identify how easily the material can be processed by injection molding or extrusion. The melt flow is directly related to molecular weight of a material, so the test provides a key indication of durability. The test is also useful for determining if a material has been degraded during processing, or if a material substitution has been made.