The present investigation proposes an experimental device able to assess the thermomechanical behavior of Ti-6Al-4V Titanium alloy throughout the die-forging operation. Constitutive equations are developed to assess the influence of the process (die-forging temperature, cooling rate) and the microstructure parameters on the mechanical response of the alloy. For this purpose, a non-unified behavior model formulation is implemented, which defines two main mechanisms related to α and β phases and allows the prediction of hardening, strain rate sensitivity and temperature, combined with the phase evolution that is dependent on the cooling conditions and which can greatly affect the mechanical behavior. This identification strategy is then applied for die-forging temperatures below the β-transus temperature, which requires microstructural information provided by SEM (Scanning Electron Microscopy) observations and image analysis. Finally, the approach is extended to die-forging temperatures above the β-transus temperature.

The article reports experiments using the Taylor test to define the dynamic behavior of brass. This material does not exhibit strain rate dependency therefore it allows the validation of an analytical description of flow stress as a function of strain with strain hardening for the data obtained from the Taylor test. The experiment is used to study the process of damage and fracture with fragmentation which is dependent on the impact velocity. Using the experimental data a numerical model of the Taylor test is developed to determine the strain level and the strain gradient along the specimen.