Integrated experimental-computational characterization of TIMETAL 21S

Accurate material constitutive parameters are important for the finite element simulation of processing, and component and structural loading. Simulations have shown that standard mechanical testing and data reduction practices can produce material property uncertainties of the order of the desired manufacturing tolerances for future components. The present study refines an integrated experimental-computational constitutive response characterization methodology that yields more accurate finite element simulations. Contrary to the previous data reduction techniques, where the goal was to produce a single uniform stress state, the new methodology seeks to generate a wide range of multiaxial stress states and then deconvolve the material response from the specimen behavior through simulation. This methodology extracts the constitutive response from experimental load-displacement test data and specimen shape evolution by constructing the material input curve from finite element simulations of the test specimen. This research includes the development of a novel test specimen to supplement the ASTM E8 specimen design, which exhibits variations in the position of strain localization along the gage length and generates a limited range of multiaxial stress states induced in the material undergoing testing. The novel specimen design examined in the present study uses a single through-thickness hole to generate the multiaxial stress and strain states. This has the added benefit of more nearly matching the stress states in actual structural components. (C) 1999 Elsevier Science S.A. All rights reserved.