ß-Phase Enhancement of Force Spun Composite Nanofibers for Sensing Applications.

In this study, a piezoelectric harvesting device was developed using polyvinylidene fluoride (PVDF) nanofibers reinforced with either BaTiO3 nanoparticles or graphene powder. BaTiO3 nanoparticles were synthesized through the sol-gel method with an average size of approximately 32 nm. The PVDF nanofibers, along with the nanoparticle composites in an acetone-N,N-dimethylformamide mixture, were produced using a centrifugal Forcespinning™ machine, resulting in a heterogeneous arrangement of fiber meshes, with an average diameter of 1.6 µm. Experimental tests revealed that the electrical performance of the fabricated harvester reached a maximum value of 35.8 Voc, demonstrating the potential of BaTiO3/ PVDF-based piezoelectric devices for designing wearable applications such as body-sensing and energy-harvesting devices.

Spark Plasma Sintering of Aluminum Nanocomposite Powders: Recent Strategy to Translate from Lab-Scale to Mass Production.

The aim of this paper focuses on presenting a recent study that describes the fundamental steps needed to effectively scale-up from lab to mass production parts produced from Al powders reinforced with 0.5 wt% of industrial multiwalled carbon nanotubes (MWCNTs), with mechanical and electrical conductivity properties higher that those measured at the lab scale. The produced material samples were produced via a Spark Plasma Sintering (SPS) process using nanocomposite aluminum powders elaborated with a planetary ball-mill at the lab scale, and high-volume attrition milling equipment in combination with controlled atmosphere sinter hardening furnace equipment, which were used to consolidate the material at the industrial level. Surprisingly, the electrical conductivity and mechanical properties of the samples produced with the reinforced nanocomposite Al powders were made with mass production equipment and were similar or higher than those samples fabricated using metallic powders prepared with ball-mill lab equipment. Experimental measurements show that the hardness and the electrical conductivity properties of the samples fabricated with the mass production Al powders are 48% and 7.5% higher than those of the produced lab samples. This paper elucidates the steps that one needs to follow during the mass production process of reinforced aluminum powders to improve the physical properties of metallic samples consolidated via the SPS process.