High-temperature plastic deformation behaviour of powder metallurgy Ti6Al4V alloy prepared from HDH powder

ABSTRACT

Powder metallurgy (PM) Ti6Al4V alloy was prepared from HDH alloy powder by vacuum pressureless sintering. To study its high-temperature deformation behaviour, isothermal compression testing was carried out with temperature range of 900–1050°C, strain rate range of 0.01–10 s⁻¹, and compression ratio of 60%. Based on the hot deformation data, the corresponding constitutive equation and hot processing map were clarified. The deformation activation energy for PM Ti6Al4V alloy was 606.5 kJ mol⁻¹. Its deformation instability zone was very small, locating in the range of 960∼990°C with strain rate >1 s⁻¹. PM Ti6Al4V alloy had large hot working window and good hot workability. The ideal hot processing domain was at 970–990°C and 0.05–0.01 s⁻¹. Besides, the domain at 1000–1040°C and 1–10 s⁻¹ was also suitable for hot processing. This study proposed an effective guidance for the hot deformation (e.g. forging, extrusion, rolling) of PM Ti6Al4V alloy.

KEYWORDS:

• PM Ti6Al4V alloy
• plastic deformation behaviour
• constitutive equation
• hot processing map
• microstructure

Acknowledgement

This work was carried out by the financial supports of the State Key Lab of Advanced Metals and Materials (No. 2019-ZD08, 2020-Z17), the National Key R&D Program of China (No. 2016YFB1101201), the Fundamental Research Funds for the Central Universities (No. FRF-GF-20-05A), the National Natural Science Foundation of China (No. 52004027), and the Guangdong MEPP Fund (Grant No. GDOE[2019]A16).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was carried out by the financial supports of the State Key Lab of Advanced Metals and Materials [Grant numbers 2019-ZD08 and 2020-Z17], the National Key R&D Program of China [Grant number 2016YFB1101201], the Fundamental Research Funds for the Central Universities [Grant number FRF-GF-20-05A], the National Natural Science Foundation of China [Grant number 52004027], and the Guangdong MEPP Fund [Grant number GDOE[2019]A16].

Notes on contributors

Haiying Wang

Haiying Wang is Ph.D. candidate in Engineering at the University of Science and Technology Beijing. She is engaged in the researches on powder metallurgy Ti alloys.

Fang Yang

Fang Yang is a Ph.D. in Engineering and works as associate professor at the University of Science and Technology Beijing. Her research interests include powder metallurgy titanium and titanium alloys, aluminum and aluminum alloys, copper and copper alloys, 3D printing, iron-based alloys, self-propagating high temperature synthesis (SHS), and magnetic materials.

Boxin Lu

Boxin Lu is Ph.D. candidate in Engineering at the University of Science and Technology Beijing. He is engaged in the researches on powder metallurgy Ti alloys.

Cunguang Chen

Cunguang Chen a Ph.D. in Engineering and works as lecturer at the University of Science and Technology Beijing. His research interests include powder metallurgy titanium and titanium alloys, aluminum and aluminum alloys, copper and copper alloys.

Zhimeng Guo

Zhimeng Guo is a Professor and PhD supervisor working at the University of Science and Technology Beijing. He is an expert in powder metallurgy titanium and titanium alloys, aluminum and aluminum alloys, copper and copper alloys, 3D printing, iron-based alloys, dispersion strengthened materials, radio frequency inductively coupled plasma spheroidization technology, self-propagating high temperature synthesis (SHS), advanced powder metallurgy technologies and materials.