Strength–ductility balance of powder metallurgy Ti–2Fe–2W alloy extruded at high-temperature


Bahador A., Issariyapat A., Umeda J., YAMANOĞLU R. , Pruncu C., Amrin A., ...More

Journal of Materials Research and Technology, vol.14, pp.677-691, 2021 (Journal Indexed in SCI Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 14
  • Publication Date: 2021
  • Doi Number: 10.1016/j.jmrt.2021.06.086
  • Title of Journal : Journal of Materials Research and Technology
  • Page Numbers: pp.677-691
  • Keywords: Grain refinement, Hot extrusion, Microstructure, Solid solution, Tensile properties, α + β Ti alloys

Abstract

© 2021 The AuthorsThis study aims to improve the mechanical properties of a Ti–2Fe base alloy by adding W solute and performing hot extrusion at a high temperature (1000 °C). W was added at 0, 1, 2, and 3 wt% using the powder metallurgy route and homogenization heat treatment. The as-extruded materials predominantly consisted of α phase with different microstructure morphologies; Ti–2Fe and Ti–2Fe–1W contained equiaxed α grains, while Ti–2Fe–2W and Ti–2Fe–3W showed equiaxed + acicular and acicular shape, respectively. Effective grain refinement was obtained in Ti–2Fe–2W (average grain size: ~1.64 μm), which greatly contributed to the strengthening. The solid solution of W was studied with X-ray powder diffraction, where a proportional increment of β lattice constant occurred as the W solute increased in the matrix (Ti–Fe). Additionally, electron backscatter diffraction analysis revealed that the W solution reduced the intensity of the prismatic texture along the extrusion direction. Based on the experimental evaluations, extruded Ti–2Fe–2W alloy exhibited a maximum yield strength of 925 MPa with excellent elongation 30% at room temperature, indicating a remarkable trade-off in strength and ductility.