Modelization and Validation of Ti-6Al-4V Alloy Material Constitutive Law for Isothermal Forging Process

Abstract:

Isothermal forging is a near-net shape forming technology for manufacturing complex titanium alloy components. In order to characterize the workability of Ti-6Al-4V alloy during isothermal forging process, the material properties of Ti-6Al-4V alloy were investigated by isothermal compression tests under different strain rate-temperature, where the temperature range is 850~1000 °C and strain rate range is 0.001~0.05s⁻¹. The obtained flow stress-strain data was used to develop the Arrhenius constitutive model of which material constants considered the compensation of strain. The developed constitutive model was used to simulate the isothermal forging process of Ti-6Al-4V alloy component by finite element (FE) based numerical method. The metal flow and potential defect locations were predicted by numerical simulation. Furthermore, the relevant simulation results were compared with the product in industrial workshop to demonstrate the validity of material constitutive model. Keywords: Isothermal forging; Ti-6Al-4V alloy; Hot compression test; Arrhenius constitutive model; FE analysis; Model validation;

• Periodical: Key Engineering Materials (Volumes 622-623)
• Pages: 207-216
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.622-623.207
• Online since: September 2014
• Authors: Chao Zhang*, Xiao Guang Yang, Jian Hua Zhou, Ai Jun Huang
• Keywords: Arrhenius Constitutive Model, FE Analysis, Hot Compression Test, Isothermal Forging, Model Validation, Ti-6Al-4V Alloy

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