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Research Interests

Ceramic Matrix Composites (CMCs)

One potential disadvantage of ceramics when compared to other materials is their relatively poor fracture toughness. The introduction of ceramic matrix composites (CMCs), in which ceramic particles, whiskers, or fibres are embedded within a ceramic matrix, has improved the fracture toughness of ceramic materials by an order of magnitude. High fracture toughness CMCs typically comprise of continuous silicon carbide (SiC) or carbon (C) fibres in their respective matrices, i.e., SiC/SiC and C/C. Applications of high strength, high fracture toughness CMCs include high temperature (>1200 ^oC) space and aerospace structures. Future projects will involve the manufacture and characterisation of CMCs.

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Ceramic Materials

Ceramic materials may be tailored to possess a wide variety of physical and mechanical properties, making them useful for applications such as high temperature structural materials, electronic materials, and biomaterials. Examples of ceramic materials include silicon nitride (Si₃N₄) and silicon carbide (SiC) (high temperature structural materials), alumina (Al₂O₃) and aluminium nitride (AlN) (electronic materials), and hydroxyapatite (Ca₁₀(PO₄)₆(OH)₂) and zirconia (ZrO₂) (biomaterials). Future projects will involve the manufacture and characterisation of advanced ceramic materials.

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Polymer Matrix Composites (PMCs)

Polymer matrix composites (PMCs), comprising of particles, whiskers, or fibres embedded within a polymer matrix, possess significantly higher fracture toughness and stiffness values compared to standard polymeric materials. The most utilised types of PMCs are the glass fibre reinforced polymer (GFRP) and carbon fibre reinforced polymer (CFRP) composites, with applications including the reinforcement of civil engineering structures and lightweight aerospace structures. One particular group of PMCs is known as a "hybrid" composite and contains two or more types of fibre reinforcement, e.g., glass/carbon and carbon/aramid. Future projects will involve the manufacture and characterisation of PMCs.

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Failure of Brittle Materials 

The standard theory of failure for brittle materials normally assumes a large number of randomly oriented flaws, leading to a Weibull distribution for cumulative failure versus strength. However, in many cases the flaw population within a brittle material does not conform to this ideal, such as the case of most ceramics which contain two distinct flaw populations, i.e., surface flaws and internal flaws. Another example might be that of anisotropic materials in which the flaw population is preferentially oriented. Future projects will involve theoretical considerations and statistical simulations of failure within brittle materials containing non-ideal flaw populations.

See also: Publications & Downloads