Effects of Curing Cycle and Loading Rates on the Bearing Stress of Double Shear Composite Joints
This study investigates the effects of curing cycle and loading rates on the bearing stress of double shear composite joints. This study investigates through experimental and numerical analysis, the mechanical behavior of double shear joints. Unidirectional MTM 49 carbon fiber was tested with two different cure cycles (recommended datasheet cure cycle and an alternate cure cycle) and 5 different loading rates 1.27 mm/min., 2.54 mm/in., 25.4 mm/in., 50.8 mm/min. and 152.4 mm/min. (0.05 in./min., 0.1 in./min., 1 in./min., 2 in./min. and 6 in./min.). The first cure cycle used was called the alternate cure cycle, which was Cytec’s MTM 49 Unidirectional Carbon Fiber pre-preg material cure cycle, and the second cure cycle used was called the datasheet cure cycle, which is Umeco's MTM 49 Unidirectional Carbon Fiber pre-preg material cure cycle. The recommended datasheet cure cycle and the alternate cure cycle were both compared to see how they affect the mechanical characteristics of the matrix along with the bearing stress. The double shear composite specimens were made, using a heat press, with a quasi-isotropic laminate orientation of [0 0 +45 -45 +45 -45 90 90]s. One can see that at 1.27 mm/min. (0.05 in./min.) and 2.54 mm/in. (0.1 in./min.) (for both cure cycles) the specimens carried more load compared to the higher loading rates of 25.4 mm/in., 50.8 mm/min. and 152.4 mm/min. (1 in./min., 2 in./min. and 6 in./min.).
Author: Mateja Andrejic
Conference: SAMPE Seattle 2017