Correlation between von Mises strain and material thinning in a hydroformed sample of Ti35A aerospace grade titanium

Bell, Colin and Jump, Ellen and Kerr, William and Corney, Jonathan and Zuelli, Nicola and Savings, David (2017) Correlation between von Mises strain and material thinning in a hydroformed sample of Ti35A aerospace grade titanium. In: Proceedings of the 20th International ESAFORM Conference on Material Forming, ESAFORM 2017. AIP Conference Proceedings, 1896 . American Institute of Physics Inc., [Melville, New York]. ISBN 9780735415805

[img]
Preview
Text (Bell-etal-ESAFORM-2017-Correlation-between-von-Mises-strain-and-material-thinning)
Bell_etal_ESAFORM_2017_Correlation_between_von_Mises_strain_and_material_thinning.pdf
Accepted Author Manuscript

Download (617kB)| Preview

    Abstract

    This paper presents the results of an experimental investigation of the strain measured on a sample of Ti35A (commercially pure) titanium that was formed past the point of failure in a hydroforming operation. The sample was etched prior to forming to allow for a strain map of the exterior to be created and examined by using a circle grid analysis (CGA) technique. The sample was scanned post forming with precise optical inspection to ascertain an accurate model of its geometry. This paper discusses the results of the analyses including the full geometric and surface strain measurements. This paper then compares material thinning properties to strain values and finds a linear relationship of approximately 3:1 between Von Mises strain and material thinning percentage throughout the sample. The slope of the line appears to correlate strongly with the material's Poisson's ratio and could have potential uses in process planning.