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The reliable performance of critical components working under extreme conditions is paramount to the safe operation of aircraft, and material selection is critical. Copper alloys are an obvious choice for such applications whenever a combination of transport, mechanical and tribological properties is required. However, low strength and hardness issues require development of new copper alloys and composites to improve service life and reliability. This study aims to investigate the effect of carbon nanotubes as reinforcement phase in copper-matrix composites.

The development of novel copper-based composites refined to the nanoscale was envisaged through mechanical milling of mixtures containing copper and carbon nanotubes (2 Wt.%). Milling took place in a planetary ball mill for times varying between 1 h and 16 h at 400 rpm. A ball-to-powder ratio of 20:1 and alumina vial and copper spheres were used under dry conditions or with addition of isopropyl alcohol. Scanning electron microscopy/energy dispersive spectroscopy, size distribution, Raman spectroscopy and X-ray diffraction were used to study the produced powders.

Attained results show that mechanical milling of the studied system produces nanostructured powders containing second-phase carbon nanotubes homogeneously distributed in the metallic matrix, together with severe copper grain refinement. This should correspond to increased residual microstresses, envisaging significant improvement of mechanical properties of the produced copper composites.

The novelty of the work resides in the use of carbon nanotubes for the reinforcement of copper, and on the systematic microstructural characterisation of the produced composites.

The purpose of this paper is to assess women winemakers’ motivations for and objectives in creating a formal, horizontal, and inter-organizational network in Portugal. To this end, an analysis was carried out of the practical case of a network of women wine producers from some of the main wine regions of Portugal (i.e. D’Uva – Portugal Wine Girls).

Qualitative data analysis was carried out of in-depth semi-structured interviews with seven wine producers and the network manager. The content analysis of interviews was done with QSR International’s NVivo Version 11 software.

The results support the conclusion that the D’Uva – Portugal Wine Girls network promotes the creativity and innovation fundamental to communicating unique features to consumers. These are narrated in a feminine, cohesive, and united voice and supported by a passion for winemaking. The network is open to adding other women producers, which could contribute to its growth and further sharing of knowledge, contacts, and experiences.

The findings provide a better understanding of the processes of internationalization and networking among women winemakers in Portugal.

The benefits of this network in terms of relationships were examined, showing that the stimulation of better performance and the effects of antecedents were important in the creation and formalization of the network.

This research sought to contribute to the literature on female entrepreneurship and, more specifically, networks of entrepreneurial women. The findings stress that, through the formalization of networks, women can gain more advantages, namely, sharing knowledge and experiences, increasing their level of internationalization, and expanding their networks.