DMTC has been awarded new funding under the Defence Innovation Realisation Fund (DIRF), to address a lack of dermal protection solutions from aerosolised hazardous chemical, biological or radiological substances. The funding will be directed towards developing a membrane protective adsorbent composite technology, aerosol vapour fabric, aiming to exceed the capability of current systems through the use of a novel adsorbent-nanofibre membranes and will address formal ADF requirements as formulated under JP2110. DMTC will work with DSTO and a range of industry and research partners to achieve these aims.
The funding is one of six DIRF grants announced by Senator the Hon David Johnston, Minister for Defence at the Defence and Industry conference this week.
DMTC is proud to have been presented with the “Most Improved” award as part of the Enterprise Connect – Supplier Continuous Improvement Program. Presented at the Defence and Industry Conference in Adelaide, the award was bestowed for demonstrating the most improvement between cycles in diagnostics scores for Business and Office Excellence.
DMTC’s Continuous Improvement Program ensures that R&D projects are conducted, and will continue to be conducted, in a manner that maximises value for money for partners and Defence.
DMTC would like to thank Enterprise Connect and in particular the Defence Industry Innovation Centre facilitators that have worked with DMTC over a number of years. Their expertise and guidance in implementing Continuous Improvement programs has been invaluable and ultimately lead to the success of our program.
DMTC has been progressing Australia’s industrial knowledge of four types of additive manufacturing through a detailed benchmarking program. The four additive manufacturing techniques that have been compared for application on metallic components are Selective Laser Melting (SLM), Electron Beam Melting (ARCAM), Direct Metal Deposition (DMD) and Wire and Arc Additive Layer Manufacturing (WALAM). The program has examined the evolution and character of the deposited metal for each of the four processes, and will go on to conduct a cost benefit analysis of their application.
Previous work has identified that additive manufacturing processes create residual stresses in the region in and immediately below the processed area. These stresses when tensile in nature compromise the structural integrity of the component. Due to this, understanding the tension or compression distribution and magnitudes for the different additive manufacturing technologies becomes a critical piece of information when selecting one of the four techniques for a particular application.
The Australian Nuclear Science and Technology Organisation (ANSTO) has provided access to and ‘beam time’ on their neutron strain scanner known as “KOWARI” to measure the residual stresses induced by each of the additive manufacturing techniques. Ti-6AL-4V samples were created in the shape of a wedge to imitate the effect of section thickness on residual stress formation. Strain maps of the four samples were then measured in ANSTOs neutron beam.
The results showed that that ARCAM, DMD and WALAM processes all produce a very low residual stress. SLM on the other hand was shown to produce a compressive stress state. This is exciting as compressive residual stresses are known to increase the structural integrity of metallic structures and therefore extend the fatigue life. This result makes SLM a more promising technology for future production of aerospace components.
Lightweight body armour systems are typically made of high hardness, low density ceramic tiles. Ceramics are arguably the best material for this application as they have a high specific compressive strength and are very effective at blunting or in some cases fracturing projectiles. Despite its overall suitability, a number of challenges with many of the ceramics used in armour systems remain, including limited formability and poor multi-hit capability.
DMTC researchers at VCAMM and Deakin University are looking at alternative materials and systems in an effort to provide new solutions for body armour that can deliver both increased performance and reduced weight. One system under investigation is a material known as ‘Polymer Ceramics’. This material is an aggregate composite produced by infusing hard ceramic particulate with high modulus polymers and nano-technology. The resulting material has been shown to offer a number of advantages over traditional ceramics including low temperature processing, ease of moulding and extreme multi-hit performance. Even in these early stages of assessment the materials has been shown to achieve 80% of the ballistic performance of silicon carbide.
Recent work has focused on improving the interfacial adhesion between the ceramic and the polymer which is believed to be the primary driver of the overall ballistic performance of the composite. To improve the interface, a silane treatment has been developed that modifies the surface of the ceramic particulates at the nano-scale. In combination with a fluidised bed treatment, this nano-scale surface modification is akin to depositing nano-sized hairs on the surface and thereby increasing the area for adhesion. The silane treatment of boron carbide led to 35% higher yield strength at break and 24% increase in modulus compared to untreated formulations. It is anticipated that the improved yield strength and modulus through silane treatment will bring the material to within 90% of the ballistic performance of silicon carbide. The ultimate goal of the research is to achieve equivalent ballistic performance to silicon carbide and thus create a more cost effective and easily fabricated body armour material option.
