Rights: The University of Waikato Published 17 September 2009 Download

In this video, Professor Deliang Zhang talks about some of the technical challenges that his research team face. Titanium has an affinity for oxygen, so most of the work has to be carried out in an inert atmosphere. The presence of oxygen in the metal can make it brittle.

Point of interest
The gas cylinders (coloured green) being adjusted by Stella Rayanova, Deliang’s research assistant, contain argon gas, which provides the inert atmosphere needed in the chamber.


The technical challenge is that the titanium is highly reactive, and also titanium has high affinity to oxygen, and also titanium metal should not have too much oxygen in it, because if oxygen content in the titanium metal is higher than say 0.5 weight percent – the material is very strong, that is not problem, but it becomes quite brittle – so brittle that the industry don’t normally like to use such material.

And when we are dealing with the powder – as you know, the powder particles have a large total surface area, so it’s quite difficult to prevent the interaction between the powder and the oxygen – so what we do is we have to design an environment which will not have much oxygen in it or even have no oxygen in it, so that we do the powder metallurgy process inside an inert environment.