Papers by Author: Bruno A. Latella

Abstract: Epoxy composites reinforced with recycled cellulose fibre (RCF) have been synthesized and characterized. The reinforcement by RCF has resulted in a significant increase in the strain at break, fracture toughness and impact toughness but moderate increase in flexural strength and flexural modulus. The effect of seawater soaking on the flexural and impact properties has also been investigated. The micromechanisms of toughening and crack-tip failure processes are identified and discussed in the light of observed microstructures from in-situ and ex-situ fracture.

Abstract: In this study the creep behaviour and adhesion characteristics of hybrid sol-gel silica-based coatings on copper substrates was examined. Sol-gel technology was used to synthesize the organically modified silanes using mixtures of tetraethoxysilane and glycidoxypropyltrimethoxysilane precursors. The creep properties and adhesion behaviour of the coatings were assessed using nanoindentation and microtensile testing, respectively. The link between film structure and creep behaviour was explored. It is shown that the creep response of the coatings is influenced dramatically by the introduction and quantity of the organic substituent.

Abstract: Reaction sintering and hot-isostatic-pressing (HIP) have been used for the compaction and densification of mullite-whisker-reinforced alumina composites. The effect of alumina matrix constraints on the in-situ transformation sequence in alumina-halloysite-AlF3 system was studied using differential thermal analysis. The physical and mechanical properties of the HIPed samples have been characterized in terms of bulk density, apparent solid density, porosity, Young’s moduli, flexural strength, hardness and the fracture toughness.

Abstract: The microstructure, mechanical, impact and fracture properties of Australian bamboo have been investigated. The graded composition and property has been confirmed by depth-profiles obtained by synchrotron radiation diffraction and Vickers indentation. The mechanical performance of bamboo is stronly dependent on age. Results showed that young bamboo has higher strength, elastic stiffness and fracture toughness than its old counterpart. Both crack-deflection and crackbridging are the major energy dissipative processes for imparting a high toughness in bamboo.

Abstract: In the biomedical field, the surface modification of titanium aims to inhibit wear, reduce corrosion and ion release, and promote biocompatibility. Sol-gel-derived ceramic nanoscale coatings show promise due to their relative ease of production, ability to form a physically and chemically uniform coating over complex geometric shapes, and their potential to deliver exceptional mechanical properties due to their nanocrystalline structure. In this study hydroxyapatite coatings on titanium were investigated for their fracture toughness.