Researchers assess additive manufacturing for JSF parts

Australian researchers are assessing the feasibility of using additive manufacturing to produce small titanium components for the Joint Strike Fighter (JSF).

The research project is a collaboration between RMIT, the Defence Materials Technology Centre (DMTC), Lockheed Martin, 3D Systems, the University of Wollongong and the Defence Science and Technology Organisation (DSTO).

‘Initially we want to find out the effects of various parameters on the microstructure of the built titanium structures and the difference in mechanical properties between vertical and horizontal builds,’ said project lead Prof Milan Brandt from the school of aerospace, mechanical and manufacturing engineering at RMIT. ‘This will then be used to redesign and manufacture the components based on bionic principles.’

An important aspect of the JSF programme is reducing the cost of manufacturing titanium components, which are attractive because of their high strength-to-weight ratio, the ability to retain that strength at high temperatures and high corrosion resistance compared to other alloys.

Prof Brandt said a major problem of manufacturing components from titanium alloys was the high rate of wastage. Technologies that cut waste would significantly impact the cost of manufactured titanium components.

RMIT University academics are looking at the use of selective laser melting (SLM) equipment to make small but expensive titanium-based components.

This method spreads a fine metallic powder in a thin layer typically 50 micrometres thick. A laser beam scans along a path based on the shape of the part to be manufactured, melting the powder and fusing it to the layer below and producing a metallurgical bond between them.

‘At the end of the day it is all leading to manufacturing small-scale JSF titanium components more efficiently and effectively while maintaining their quality and integrity,’ said Brandt.

‘On the fundamental scientific level our objective is to increase the understanding of the SLM process and translate that into practical information for uptake by industry.’