A novel method of tube manufacture for vehicle crashworthiness utilising the QUICKSTEP™ Process.

A novel method of composite tube manufacture was developed for potential use in automotive crash structures. Tubes were crushed axially under quasi-static conditions and highly repeatable behaviour was observed with an average specific energy absorption of -85kJ/kg. DMTA results indicated that the tubes were fully cured, even when the cycle was reduced to 7 minutes, giving this process huge potential for high-volume production.

Manufacturing process effects on the mode I interlaminar fracture toughness and nanocreep properties of CFRP

Quickstep ™ is a fluid filled floating mould technology which was recently developed by an Australian company of the same name. The Quickstep and conventional autoclave manufacture of composites were compared by investigating the mode I interlaminar fracture toughness and nanocreep propeties of HexPly914 carbon epoxy composites. It was found that composites cured using the Quickstep technology had significantly higher fracture toughness (1.8 times) than the composites cured via autoclave for this system. DMTA (dynamic mechanical thermal analysis) results showed a higher Tg (glass transition temperature) for the material manufactured by the Quickstep than that cured by the autoclave. FTIR (Fourier transform infrared spectroscopy) spectra did not indicate any difference in cure chemistry between the two processes. Nanocreep experiments were performed to explore the viscoelastic properties of the epoxy matrix of composites. The KelvinVoigt three-element model was applied to analyse the indentation creep behaviour of both composites.

Plastic deformation in Zr41 Ti14 Cu12.5 Ni10 Be22.5 bulk metal glass under vickers indenter

Vickers indentation was conducted on an as-cast Zr41Ti14Cu12.5Ni10Be22.5 bulk metal glass (BMG) to study shear band formation using a bonded interface technique. The results indicate that the plastic deformation in the BMG is accommodated by the semi-circular (primary) and radial (secondary) shear bands. The inter-band spacing of the semi-circular shear bands is found to be independent of the applied load. The measured size of the deformation zone is in good agreement with the prediction of the theoretical model proposed by Zhang et al.

Stephen Procter: reflections of a glass artist

Stephen Procter: Reflections of a Glass Artist, records the thoughts and philosophies of the artist and glassmaker who for a number of years headed the Glass Department of the Australian National University School of Art. It traces his career in glass working from his first interest developed through a pointillist technique while living on Dartmoor; through his British Council-funded grant that enabled him to learn glass blowing and cutting techniques in Austria; to the mature landscape paintings and glass sculptures created during his years living in Australia.

Effects of quenching rate on amorphous structures of Cu46Zr54 metallic glass

Metallic glass shows some superior properties different from crystalline, but the nature of amorphous structure and structural change during glass transition have not been completely understood yet. Molecular dynamics simulation provides intuitive insight into the microstructure and properties at atomistic level. Before probing into the microstructures of metallic glass with molecular dynamics (MD) simulation, it is important to obtain amorphous state first. In the current work, we reproduce the process of manufacturing metallic glass in laboratory including the melting, equilibrating and quenching procedure with molecular dynamics simulations. The structure changing at melting point and glass transition temperature are investigated with the different cooling processing. The partial radial distribution function (PRDF) is applied as a criterion to judge the final amorphous state obtained considering the quenching at different cooling rates and the effects of cooling rate on the formation of amorphous structures are further discussed.

Weaning and growth of Anguilla australis glass eels and elvers

Anguilla australis glass eels proved to be resilient and present strong aquaculture potential. General husbandry techniques, anaesthesia and prophylactic treatments were established for glass eels between 0.1 g and 2.0 g and elvers between 2.0 g and 8.0 g, caught in rivers and estuaries along the South East Coast of Victoria. The protozoan parasites Ichthyobodo and Trichodina were found to be present on arrival to the hatchery developed during different rearing treatments, and were successfully eradicated. A. australis glass eels accepted artificial food, but it was recommended first be fed a preweaning diet of minced fish flesh. A weaning regime from minced fish flesh to commercially available eel grower mash, over 15 days was established. Growth rate proved to be highly variable, both between and within groups. The highest growth rate of 2.71%/day was found when the natural diet of minced fish and Artemia was fed. The maximum growth rate when reared on an artificial diet of 1.63%/day was observed at 25°C. Growth was affected by the presence or absence of a preweaning diet, weaning diet, weaning period, temperature, but not by size or density. Once weaned, glass eels were found to perform better on commercially available grower mash than on the minced fish flesh, which was used to aid in weaning them to artificial diets. Of the water quality parameters measured stocking density was found to affect pH, Total Ammonia Nitrogen, Total Phosphorus, and Dissolved Oxygen, through not to an extent which affected growth.

Effects of quenching rate on amorphous structures of Cu46Zr54 metallic glass

Metallic glass shows some superior properties different from crystalline, but the nature of amorphous structure and structural change during glass transition have not been completely understood yet. Molecular dynamics simulation provides intuitive insight into the microstructure and properties at atomistic level. Before probing into the microstructures of metallic glass with molecular dynamics (MD) simulation, it is important to obtain amorphous state first. In the current work, we reproduce the process of manufacturing metallic glass in laboratory including the melting, equilibrating and quenching procedure with molecular dynamics simulations. The structure changing at melting point and glass transition temperature are investigated with the different cooling processing. The partial radial distribution function (PRDF) is applied as a criterion to judge the final amorphous state obtained considering the quenching at different cooling rates and the effects of cooling rate on the formation of amorphous structures are further discussed.

Plastic deformation in the annealed Zr41Ti14Cu12.5Ni10Be22.5 bulk metal glass under indenter

Vickers and nanoindentationswere carried out on an annealed Zr₄₁Ti₁₄Cu_12.5Ni₁₀Be_22.5 bulk metallic glass (BMG), and the evolution of the shear bands in the annealed BMG was investigated and compared to that in the as-cast alloy. Results indicate that the plastic deformation in the BMG with the structure relaxation is accommodated by the semicircular (primary) and radial (secondary) as well as tertiary shear bands. Quantitatively, the shear band density in the annealed alloywas much lower than that in the as-cast alloy. The load-displacement curve of nanoindentation test for the annealed alloy exhibited a more flat serrated flow. The annihilation of free volume caused by the annealing was responsible for the embrittlement of the annealed sample.

Development of positioning jig for glass capillary bending mechanism

In a bending mechanism for glass capillary, the positioning jig to hold the capillary in place is one of the most important components to ensure the bending quality. The tapered shoulder of the capillary is used as the positioning reference. Since the dimension of the shoulder of individual capillaries varies slightly, the geometry of the capillaries is studied to identify the desired positioning spot on the shoulder. Upon determination of the positioning spot, a positioning jig is designed, which is composed of positioning, holding, and clamping units. A prototype is made and assembled onto the bending mechanism for testing. The testing results show that the mechanism is able to achieve the desired functionalities demanded by the delicate bending process.

Mg-based metallic glass / titanium interpenetrating phase composite with high mechanical performance

We report an Mg-based metallic glass/titanium interpenetrating phase composite in which constituent phases form a homogeneously interconnected network. The porous titanium constrains shear bands propagation thoroughly and promotes shear bands branching and intersection subsequently. The homogeneous phase distribution promotes regularly distributed local shear deformation and leads to a uniform deformation for the composites. Moreover, the interpenetrating phase structure introduces a mutual-reinforcement between metallic glass and titanium. Therefore, the composite exhibits excellent mechanical performance with compressive fracture strength of 1783 MPa and fracture strain of 31%.

Extrusion properties of a Zr-based bulk metallic glass

The extrusion behavior of Zr_41.2Ti_13.8Cu_12.5Ni₁₀Be_22.5 metallic glasses in the supercooled liquid region was investigated. Good extrusion formability was observed under low strain rates at temperatures higher than 395 °C. The metallic glasses were fully extruded without crystallization and failure within the range of T=395–415 °C under strain rates from 5×10⁻³ s⁻¹ to 5×10⁻² s⁻¹, and the deformation behavior of the metallic glasses during the extrusion was found to be in a Newtonian viscous flow mode by a strain rate sensitivity of 1.0.