Metallurgical Engineering

Metallurgical Engineering

Numerical and Experimental Investigation of Hot Deformation Behavior of Ti6Al4V with an equiaxed α–β microstructure

Document Type : Research Paper

Authors
Alijanzadeh Hossein 1
Bagher Mohammad Sadeghi 2
Seyed Hossein Razavi 2
Bahman Mirzakhani 3
1 School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran, Iran.
2 School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran, Iran
3 Department of Material Science and Engineering, Faculty of Engineering, Arak University, Arak, Iran.
10.22076/me.2023.562649.1368
Abstract
In this study, the hot deformation behavior of Ti6Al4V alloy with an equiaxed microstructure (alpha/beta) was investigated using the Zener–Hollomon parameter and processing maps. Firstly, the stress-strain curves were derived from the hot compression tests, which were conducted at temperatures of 800 to 950°C and strain rates ranging from 10-3 to 1 s-1. Following the determination of the constants of the constitutive equations (ln A, α, n and Q) by using experimental flow curves, predicted flow curves were plotted. On the other hand, microstructural examinations and hardness tests were performed to reveal the microstructural changes and the heterogeneity index. The SimuFact-Forming (FEM) software was also used to simulate stress and strain distributions and dimensional changes in the test samples, as well as force-displacement curves during the hot compression tests. Based on the comparison results, it can be concluded that the hyperbolic sine equation provides more accurate approximations of the Zener-Hollomon parameter and the flow stress. According to the processing maps, the highest power dissipation efficiency was observed within the temperature range of 900 to 950 °C and the strain rate range of 0.3 to 1. Moreover, the unstable zones of processing map were indicated at low temperatures and strain rates (the temperatures between 800 and 840 °C within a strain rate of 10-3 to 0.03). The results showed that the force-displacement curves obtained from finite element simulations were in good agreement with those obtained from experiments.
Keywords
Ti6Al4V Alloy
Equiaxed Microstructure
Hot deformation
Constitutive Equations
Processing Map
Finite Element Simulation
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Metallurgical Engineering
Volume 28, Issue 2
Summer 2025
Pages 72-88

  • Receive Date 26 September 2022
  • Revise Date 27 August 2023
  • Accept Date 14 November 2023