of validation of the constitutive equations – Experimental approach

Abstract. The validation of constitutive equations currently based on sphere expansion or Taylor test is difficult to obtain for fragile materials, which are fractured in traction for weak deformations. It is thus preferable, for these materials, to choose a test such as the cylindrical implosion for which the material is under compression. The study presented relates to the experimental validation of a cylindrical device of implosion, which was developed on titanium (TA6V4). The major innovations related to this experimental configuration are the use of high explosive and the instrumentation implemented. The velocity of a conical titanium sample is measured using IDL and VISAR techniques. The results indicate that deformations close to 20 % were thus obtained. They enable us to validate the technology and the instrumentation implemented. A first comparison simulation-experiment is carried out. 1