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  • In search of the optimal conditions to process shape memory alloys (NiTi) using fused filament fabrication (FFF)
    Publication . Carreira, Pedro; Cerejo, Fábio; Alves, Nuno; Vieira, Maria Teresa
    This research was performed so as to investigate the additive manufacturing of NiTi shape memory alloys, which is associated with direct processes, such as selective laser melting. In addition to its expensive production costs, NiTi readily undergoes chemical and phase modifications, mainly as a result of Ni loss during processing as a result of high temperatures. This research explores the potential usefulness of NiTi as well as its limitations using indirect additive processes, such as fused filament fabrication (FFF). The first step was to evaluate the NiTi critical powder volume content (CPVC) needed to process high-quality filaments (via extrusion). A typical 3D printer can build a selected part/system/device layer-by-layer from the filaments, followed by debinding and sintering (SDS), in order to generate a near-net-shape object. The mixing, extruding (filament), printing (shaping), debinding, and sintering steps were extensively studied in order to optimize their parameters. Moreover, for the sintering step, two main targets should be met, namely: the reduction of contamination during the process in order to avoid the formation of secondary phases, and the decrease in sintering temperature, which also contributes to reducing the production costs. This study aims to demonstrate the possibility of using FFF as an additive manufacturing technology for processing NiTi.
    2020-10-22Journal article Open access Show more
  • Young People’s Perceptions about the Difficulties of Entrepreneurship and Developing Rural Properties in Family Agriculture
    Publication . Yamaguchi, Cristina Keiko; Stefenon, Stéfano Frizzo; Ramos, Ney Kassiano; Santos, Vanessa Silva dos; Forbici, Fernanda; Klaar, Anne Carolina Rodrigues; Ferreira, Fernanda Cristina Silva; Cassol, Alessandra; Marietto, Marcio Luiz; Yamaguchi, Shana Kimi Farias; Borba, Marcelo Leandro de
    This article aims to understand the perceptions of young rural entrepreneurs about the difficulties in investing in family farms in which they work. Ninety-eight people were interviewed at the event “Meeting of Young Entrepreneurs of the Rural Environment of Santa Catarina: the rural youth leading the sustainable development”, held in May 2019. The methodology applied in this paper is qualitative and quantitative, through a bibliographic review and a numerical analysis on work conditions and workers’ profile. A brief theoretical background is presented to facilitate the understanding of the results and their relation to family farming, entrepreneurship and its reality in Brazil. As a result, the economic issue was pointed out with 34% of the cases, as a hinter to undertake in rural properties, followed by the lack and low qualification of the workforce available with 12.6% of the cases and the lower selling price for the producer with 7.6% of the cases.
    2020-10-22Journal article Open access Show more