A CO 2 Q-switched pulsed laser system with a peak power of 50 W was used for adherends pre-treating. After the polymerization and demolding of the laminates, they were polished using acetone to avoid the possible contamination of the surfaces with release agents. In this way, the manufactured adherends presented a thickness of 2.4 mm. The layup chosen for the activity was a s. The mechanical properties of the prepreg in the cured state are reported in Table 1. The laminates used for the production of ENF specimens were made by vacuum bagging molding using a unidirectional carbon fiber prepreg known as CYCOM T152/X751/135. The reliability of a bonded joint is closely related to the chemical compatibility between the substrates, the nature of the adhesive and adherends, the geometric configuration of the joint, the working conditions, and, in particular, the pre-treatment of the surfaces to be bonded, as shown in many works in the literature. Since it is not necessary to drill the parts, the use of structural adhesives is indicated in the case of assembly of components in polymeric composite materials, reducing weight, avoiding the presence of corrosive problems, allowing to dampen the vibrations, and, consequently, the reduction of vibroacoustic activity. As an alternative to traditional fastening, such as riveting and bolting, the development of high-performance structural adhesives has grown in recent decades. In addition, the presence of holes can generate intensification of stresses that can cause structural failure during the use of the component. Traditional jointing techniques, such as riveting and bolting, require the drilling of the parts: it follows that the reinforcement must be cut, reducing their performance. Nevertheless, the designers must take the presence of joints into account as they may have critical points. the trend is to manufacture an assembly consisting of n-parts of simpler geometry. However, at present, it is not always possible to produce complex geometries with this type of material in a single production step therefore. In this context, the use of fibro reinforced polymeric composite materials, thanks to their peculiarities, play a fundamental role in achieving such performance. The aerospace and military industries more and more often require the manufacturing of complex geometry lightweight components with high specific strength and stiffness.
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