Tougher alloys for titanium tanks

Military vehicles could be armoured with titanium alloys better able to withstand bullets and explosions in the future.

The tougher material is the intended result of research being conducted by Prof Wei Sha at Queen's University's School of Planning, Architecture and Civil Engineering.

Sha is developing computer models that will reveal the reasons why titanium deforms and retains damage from strong impacts and fast applied forces.

Such compression on the metal can happen when it is hit by bullets or explosives.

In this occurrence the temperature inside the alloy can heat up to several hundred degrees through heat generated by deformation. Sha has discovered that titanium, like other metals, can be weakened by such forces and elevated temperatures. If these alloys are damaged they can endanger the lives of those relying on their protection.

‘If we can understand how the metal will deform under impact loading then we can control the damage to the finished product,’ he said.

Sha’s computer models will be based on metallurgy theory, hoped to provide a greater understanding of the material at the atomic scale. Such models, Sha said, will not only help to improve finished titanium products, but will also improve manufacturing processes.

‘The manufacturing of the material usually involves deformation,’ he said. ‘If you want to make a tennis racquet you have to deform it to that shape. If this deformation is not done properly it will induce defects. We need to understand how the metals deform under fast loading to shape the component.’

Sha added that the model could also help the manufacturing of major titanium components for the aeronautic industry. Manufacturers will have better advice on safety, material selection, optimisation and component design.

Sha said he believes the modeling technique will cut back on costly and time consuming experimental alloy testing.

‘If we develop a computer model that can predict the behaviour of different alloys under different loading and environmental conditions then that will help reduce the experimentation work,’ he said.

Sha has worked with TIMET, a supplier of titanium products, on past research and hopes the results of his recent work will be used by their company and others like it around the world.

Siobhan Wagner