La 'Ndrangheta attraverso lo sguardo dei magistrati: una ricerca empirica

Failure mechanisms of flax/epoxy laminates with open hole: a failure map

Aim of this paper is the investigation of the pin/hole contact stress and failure mechanisms of flax/epoxy composite laminates underwent to tensile bearing tests. In particular, the maximum loads and failure modes are evaluated at varying joint geometry. In order to optimize the use of composite materials in structural applications, an experimental failure map, identifying main failure modes of mechanically fastened joints, is obtained by evaluating failure modes (i.e., net tension, shear out, cleavage and bearing) as a function of the pin diameter and the position of the hole from the free edge of the laminate. Main goal of this paper is give a simple experimental methodology to support th…

Wettability of flax/basalt reinforced composites during aging in salt spray conditions

Aim of this work was to investigate the wettability of natural fibres reinforced epoxy composites, subjected to aging tests performed on two different laminates. The first laminate was constituted by stacking ten layers of bidirectional flax fabrics. The second one was produced by replacing two external flax layers with two layers of basalt mat, for each side of the laminate. Both laminates were exposed to salt-fog environmental conditions, according to ASTM B 117 standard, for 60 days. The results of wettability were compared with those of the water uptake test. Moreover, an analysis of variance was performed in order to evaluate the significance of the parameters that influence the wettab…