Enhancing the material testing capabilities at the University of New Hampshire.

摘要

Equipment for implementing four experimental techniques for assessing the anisotropic and forming behavior of materials have been developed, designed or significantly improved upon. The first such technique is sheet hydroforming. The enhancement of an existing sheet hydroforming machine is described. The second technique is biaxial testing of sheet metal using a cruciform specimen. A table-top cruciform testing machine was designed and manufactured. This design began as a simple bolted frame with four hydraulic cylinders, each equipped with a load cell and a grip. The final design involves a stiff and precise, one-piece frame that features a kinematic coupling system to synchronize the motion of two opposing hydraulic cylinders, as well as linear guide to ensure precise translation of the grips. The third technique is the biaxial tension of tubular specimens via the simultaneous application of tension or compression and internal pressure. For that purpose, custom grips where designed to mount onto an existing servo-hydraulic testing machine. Finally, the fourth technique is tube hydroforming. An existing machine was used for the first time and preliminary hydroforming experiments were performed. In addition, uniaxial tension tests were performed on Al 5754-O and results are presented. These testing techniques expand the capabilities of the Mechanics, Materials and Manufacturing Lab at UNH for both research and education.