A semi-automated in-plane loader for materials testing
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A universal testing machine is described for applying general in-plane loading as combinations of tension or compression, shear and in-plane rotation. It is composed of three computer-controlled hydraulic actuators connected to a movable head free to execute translation and rotation motions. Test specimens 1 in.×1.5 in. (25 mm×38 mm) are loaded through hydraulic grips for which the gripping pressure can be programmed. Other components include a mechanical specimen loader, a video digitizer for defining the specimen geometry, and a computer system that controls the test and gathers and stores the test data. A large number of tests can be conducted inexpensively over a broad range of loading conditions in this system, as opposed to the more generally available complex loading systems for which specimen costs are higher and testing time considerably longer. With rather limited changes, the system could be fully automated. The system has been used to characterize the fracture behavior of a series of carbon/epoxy composites over a broad range of in-plane loads.
KeywordsFluid Dynamics Test Specimen Testing Machine Material Testing Testing Time
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