Authors: Hugo Campos, Abel D. Santos, Rui Amaral, J. Bessa Pacheco

The biaxial hydraulic bulge test allows determination of formability of sheet metal materials as well as determination of hardening laws at higher strains, when compared to uniaxial tensile results. Therefore, better accuracy can be obtained in constitutive equations used in numerical simulation. This paper presents the development and improvement of a mechanical measuring system for a hydraulic bulge test, which allows continuous data acquisition of pressure, curvature and strain. With this data it is possible to obtain the evolution of the stress-strain curve under controlled conditions of speed and strain to higher levels of plastic deformation. Results of numerical finite analysis are presented for sensitivity studies of some of the influential variables in stress/strain determination. This paper also presents experimental results for different materials, obtained with the developed data acquisition system.

Hugo Campos¹ | Abel D. Santos^1,2 | Rui Amaral¹ | J. Bessa Pacheco²
1 INEGI – Instituto de Ciência e Inovação em Engenharia Mecânica e Engenharia Industrial, Universidade do Porto
2 FEUP – Faculdade de Engenharia, Universidade do Porto