Masters thesis focuses on memory rules. Understanding of cyclic stress strain behaviour is based on former research that was mostly done with metals. Polymer breakthrough is becoming more prominent, as they are already beeing used as substitute for metals. The main goal of this work is confirmation that current known theory of memory rules does also apply for polymers. Because of general usefulness we focused on Polyamide group, more exactly we conducted resarch with Polyamide 6 and Polyamide 66 with
30% glass reinforcement. With uniaxial tests and extensive data analysis, we concluded that Polyamides in general do abide memory rules and the phenomenon is not dependant on presence of reinforcement fobers. Added reinforcements decreased variation between samples but also significantly improved strenght and stiffnes. We also proved that stress-strain response can be fairly accurately simulated with combined model of isotropic and kinematic hardening defined with Armstrong Frederick rule.
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