Advanced ceramics for armour applications have been the subject of intense development for decades, with composition and microstructures being continuously refined, incrementally increasing the ballistic performance. Nanocomposite ceramics have the potential to provide a step change in performance through the use of novel property and damage mechanisms resulting from their nanostructure. The use of nano-reinforcement in ceramics is not a new concept, and nano powders, platelets, nanotubes, and graphene have all received much attention. Many of these reinforcements require advanced processing techniques to disperse the nano element and sinter the material whilst preserving the desired nanostructure. The work presented here considers the commercial viability of the nanocomposites and attempts to utilise scalable and affordable materials and processes to produce materials with commercial viability. 
We present the work done on the development and characterisation of two nanocomposite materials, the first comprising an alumina matrix, the second with a boron carbide matrix. The microstructure and properties of these materials are appraised and compared to commercially available armour materials. The ballistic performance of the materials is also modelled, baselining against commercial materials. 
The first nanocomposite is an alumina reinforced with nano silicon carbide. The nano silicon carbide is derived from polycarbosilane in situ. Similar nanocomposites have previously been developed through hot pressing and spark plasma sintering [1], [2], but limited work had been performed on pressureless sintered materials [3]. Pressureless sintering being a requirement for any cost-effective alumina-based armour material. Here, we present an alumina-silicon carbide nanocomposite pressureless sintered to 95% dense, retaining nanophases, and presenting hardness values comparable to those of pressure assisted sintered materials (19 ±1 GPa HV2) [1]. 
The second nanocomposite material is a boron carbide reinforced with titanium diboride and silicon carbide, formed in situ from additions of titanium disilicide. This composite comprises both micro and nano-phase reinforcements formed from the reaction of the titanium disilicide with the boron carbide matrix. This produces a transient liquid phase reaction which both aids sintering and produces well dispersed micro and nano phases of silicon carbide and titanium diboride [4]. The resulting composite has a density ≥ 98% and presents hardness in excess of 34 GPa HV2. 
Both the nanocomposites use commercially available raw materials and make use of in situ formation of the nanophase. This means that the handling and dispersion of nanomaterials is not required, which significantly reduces the processing hazards and costs

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