Thermo-mechanical processing and phase analysis of titanium alloys with copper additions

  • K D Ukabhai University of the Witwatersrand
  • K T Nape University of the Witwatersrand
  • L Spotose University of the Witwatersrand
  • M Mavundla University of the Witwatersrand
  • I A Mwamba Mintek
  • M O Bodunrin University of the Witwatersrand
  • L H Chown University of the Witwatersrand
  • L H Cornish University of the Witwatersrand

Abstract

In dentistry and orthopaedics, to replace and mend broken bones, any replacement material needs to have: low density, high strength, good biocompatibility and must be able to integrate closely with the bone. Titanium-based alloys have these properties, although currently used alloys contain toxic elements, and commercially pure Ti does not have sufficient strength. Within ten years, 7% of dental implants have complete failure, mainly from bacterial infection. Therefore α + β type Ti-alloys were developed by adding b stabilisers, with similar phase proportions to Ti-6Al-4V without the toxic elements, with Cu additions for antibacterial properties and Ru for corrosion resistance. Deformation behaviour of Ti-6Al-4V and Ti-Ta-Nb Zr alloys were also studied using a Gleeble thermomechanical simulator. The compositions of the new alloys were derived using Thermo-Calc. Ti-8Nb-4Zr alloys had bimodal microstructures and the addition of Cu formed the Ti2Cu phase. The Ti-6Ta-1.5Zr and Ti-6Ta-1.5Zr-0.2Ru alloys with no Cu had coarse α lamellae, whereas the alloys with Cu had parallel α plates. The Gleeble results showed that higher flow stresses were obtained at higher strain rates and lower temperatures, agreeing with literature. At 850 °C, the Ti-6Al-4V alloy had higher flow stresses than Ti-10.1Ta-1.7Nb-1.6Zr. The Ti-6Al-4V and Ti-10.1Ta-1.7Nb-1.6Zr alloys had steady-state flow stresses at 950 °C, and continuous flow softening at 850 °C for both strain rates.

Author Biographies

K D Ukabhai, University of the Witwatersrand

School of Chemical and Metallurgical Engineering, University of the Witwatersrand, Private Bag 3, WITS, 2050, and DSI-NRF Centre of Excellence in Strong Materials, hosted by the University of the Witwatersrand, Johannesburg, Private Bag 3, WITS, 2050, South Africa

K T Nape, University of the Witwatersrand

School of Chemical and Metallurgical Engineering, University of the Witwatersrand, Private Bag 3, WITS, 2050, and DSI-NRF Centre of Excellence in Strong Materials, hosted by the University of the Witwatersrand, Johannesburg, Private Bag 3, WITS, 2050, South Africa

L Spotose, University of the Witwatersrand

School of Chemical and Metallurgical Engineering, University of the Witwatersrand, Private Bag 3, WITS, 2050, and DSI-NRF Centre of Excellence in Strong Materials, hosted by the University of the Witwatersrand, Johannesburg, Private Bag 3, WITS, 2050, South Africa

M Mavundla, University of the Witwatersrand

School of Chemical and Metallurgical Engineering, University of the Witwatersrand, Private Bag 3, WITS, 2050, and DSI-NRF Centre of Excellence in Strong Materials, hosted by the University of the Witwatersrand, Johannesburg, Private Bag 3, WITS, 2050, South Africa

I A Mwamba, Mintek

DSI-NRF Centre of Excellence in Strong Materials, hosted by the University of the Witwatersrand, Johannesburg, Private Bag 3, WITS, 2050, and Advanced Materials Division, Mintek, Private Bag X3015, Randburg, 2125, South Africa

M O Bodunrin, University of the Witwatersrand

School of Chemical and Metallurgical Engineering, University of the Witwatersrand, Private Bag 3, WITS, 2050, and DSI-NRF Centre of Excellence in Strong Materials, hosted by the University of the Witwatersrand, Johannesburg, Private Bag 3, WITS, 2050, South Africa and African Academy of Sciences, P.O. Box 24916-00502, Nairobi, Kenya

L H Chown, University of the Witwatersrand

School of Chemical and Metallurgical Engineering, University of the Witwatersrand, Private Bag 3, WITS, 2050, and DSI-NRF Centre of Excellence in Strong Materials, hosted by the University of the Witwatersrand, Johannesburg, Private Bag 3, WITS, 2050, South Africa

L H Cornish, University of the Witwatersrand

School of Chemical and Metallurgical Engineering, University of the Witwatersrand, Private Bag 3, WITS, 2050, and DSI-NRF Centre of Excellence in Strong Materials, hosted by the University of the Witwatersrand, Johannesburg, Private Bag 3, WITS, 2050, South Africa

Published
2022-01-24
How to Cite
Ukabhai, K., Nape, K., Spotose, L., Mavundla, M., Mwamba, I., Bodunrin, M., Chown, L., & Cornish, L. (2022). Thermo-mechanical processing and phase analysis of titanium alloys with copper additions. Suid-Afrikaans Tydskrif Vir Natuurwetenskap En Tegnologie / <i>South African Journal of Science and Technology</I&gt;, 40(1), 84-90. Retrieved from http://satnt.co.za/index.php/satnt/article/view/884
Section
Conference of the South African Advanced Materials Initiative