Technical Information
Impact analysis Details
Strain rate dependence of resins.
Resin has the property that its material properties vary greatly depending on the deformation speed, which is called strain rate dependency.
When the phenomenon to be predicted becomes high speed, it cannot be expressed by normal resin characteristics (low speed stress-strain curve) alone.
If the phenomenon you want to predict becomes faster, you cannot express only by the normal resin characteristics (low-speed stress-strain curve).
Asahi Kasei’s unique material model
Crystalline resins, such as polyamide, contain crystalline and amorphous parts, as shown in the figure (left).
When a dumbbell-shaped test piece of unreinforced polyamide is pulled, necking occurs as shown in the figure (right), resulting in ductile fracture. This is a characteristic unique to resins in that the polymer in the amorphous region is stretched, and fracture occurs at the boundary between the crystalline and amorphous regions.
In order to predict the fracture mode and the amount of energy absorbed at the time of fracture, we have developed a material model that takes such microscopic damage into account and applied it to impact analysis.
We have developed a material model that considers such microscopic damage and applied it to impact analysis so that we can predict the failure mode and the amount of energy absorbed at the time of failure.
● If you are interested in the equations used in the material model, please refer to the literature.
