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Activated carbon cloth dressing is an appropriate wound healing material due to its biocompatibility and adsorption characteristics. The influence of gamma radiation as a sterilization process on the adsorption and mechanical properties of activated carbon cloth was investigated. The specific surface area, micropore volume, pore size distribution, surface chemistry as well as the breaking load of activated carbon cloth before and after gamma radiation were examined. Characterization by nitrogen adsorption showed that the activated carbon cloth was a microporous material with a high specific surface area and micropores smaller than 1 nm. Gamma radiation decreased the specific surface area and micropore volume but increased the pore width. The sterilization process changed the surface chemistry quantitatively, but not qualitatively. In addition, the breaking load decreased but without any influence considering the further application of this material.

Low cost titanium alloy compacts were produced via the powder metallurgy approach through the hydride – dehydride process and hot consolidation (hot pressing and hot isostatic pressing). The conditions of the reversible hydride – dehydride process were determined by X-ray and scanning electron microscopy characterisation of powders. Powders were consolidated both above and below the β transformation temperature. The morphology of the microstructure, and the presence of open and closed pores, as well as residual particles of hydrides and oxides have a direct influence on the mechanical properties of compacts (tensile properties and impact toughness).

A review of the mechanical properties and failure initiation and propagation in carbon/epoxy composites is presented. The results of the study of the macromechanical static characteristics, non-linear elastic behavior flexural modulus and shear properties of unidirectional composites (UDC), as well as, of tensile, compression and flexural moduli, strength analysis edge and hybrid effects in multidirectional composites (MDC) were discussed A discussion of the non-linear elastic behavior of carbon/epoxy UDC, the flexural moduli of both UDC and MDC, strength analysis and edge effects of laminates is emphasized.

Hardness and Youngs modulus of the matrix and fibers in carbon/epoxy gamma irradiated and annealed composites were investigated using nanoindentation technique. The Vickers microhardness of the tested composites after irradiation and annealing was studied, as well. Gamma irradiation to various doses (5-27 MGy) of UDC plates, were followed by thermal treatments of irradiated coupons at 180 and 250 degrees C, in vacuum. The measured changes of nano and micro properties were correlated to glass transition temperatures, as well as the delamination toughness changes, determined earlier on the same material. The established irradiation and annealing effects on nanoindentation properties and Vickers mocrohardness were analyzed as a function of the matrix plasticity change. An attempt was made to assess the contribution of chain scission mechanism and the change in plasticity mechanism on the property changes from irradiation and subsequent thermal treatments. (C) 2011 Elsevier B.V. All rights reserved.