Abstract

Abstract

Abstract

One of the biggest challenges in transport industry is weight reduction. The objective is both economic and environmental: cost reduction together with a reduction in the use of fuel and CO2 emissions. Multi-material design, with rigid foams as local reinforcements, suppose a great opportunity to success this challenges, being a versatile solution for cost and weight saving. Among them, polyurethane rigid foams (PUR) not only present structural and energy absorption advantages, but also improveme other properties, as corrosion resistance and vibration and noise reduction. In the present work, extruded profiles (series 6xxx-T6) were reinforced with PUR foams manufactured by CETEC. The influence of the next factors on the structural strength has been evaluated: profiles wall thickness (from 1.6 to 4 mm), filling method (manual or injection), PUR density (from 100 to 300 kg/m3), amount of material inside the profiles (from 70 to 90%) and influence of the temperature in the PUR foaming. Improvement in the structural strength (maximum load and energy absorption) was characterised by 3-point bending test. In conclusion, it has been observed an improvement in the load and energy absorption with the inclusion of PUR, with a dependence on the wall tickness and foam density. Furthermore, injected profiles presented improved structural results due to the better control over the manufacturing process.

Abstract

The success of the European rail system requires cost-efficient passenger trains with high capability and reliability. The development of these high demanding trains involves a concerted effort in improving a comprehensive range of elements. CARBODIN contributes to this effort by combining the research effort along with the future CFM- IP1-01-2019 and the ongoing CFM-IP1-01-2017 projects to manufacture car body shell parts, doors and to improve the interior design of passenger trains.

CARBODIN improves car body shell manufacture by exploring the possibilities offered by composite materials. To this end, CARBODIN advocates for a modular tooling to manufacture a wide range of parts of varying size, leaded by EURECAT. In addition, the proposed process combines different production techniques, automation concepts, introduction of co-cured and co-bonded composite parts and multi-material integrated joints and inserts. Besides, predictive maintenance is reinforced by testing intelligent sensor nodes. Composite materials are also the core idea for cost-efficient doors with reduced LCC. The creation of modular tooling combined with 3D technology is enabling the production of lighter doors with enhanced thermal and acoustic properties in the door and its vicinity. 

Abstract

This work presents a comparison in the production of electrical conductivity polyester resins by doping it with two types of carbonous fillers; carbon nanotubes (CNT) and carbon black (CB). These polyester resins are used to obtain electrical conductivity powder gel coat. This type of coating reduces cycle times in the manufacture of composites due to the fact that significantly decrease curing time of the gel coat and eliminate secondary operations for the application of the final coating in the composite. Electrical conductivity with different fillers content and percolation thresholds obtained in the simulation phase are detailed. The results obtained in the simulation are validated at the pilot plant level taking into account the influence of the loading percentage on the resin processing. Finally, a comparison between the results obtained with the different percentage of CNT and CB is made. The results of the simulation show that the value of the percolation threshold is much lower in the case of CNT (about 3% in the case of CNT versus 35% in the case of CB). The experimental results indicate the strong dependence of the electrical properties on the production process obtaining variations of up to two orders of magnitude in the experimental results using the same percentage of CNT but different type of polyester resin.

Abstract

The diffusion or permeability of ions or gases through the cement matrix is key in the degradation of reinforced concrete for marine applications. The delay in ion diffusion has been an important approach to extend the life of this type of materials. In this work it is detailed how reduce degradation of cement mortar using nanotechnology. The addition of nanoparticles to the cement paste has important implications for the hydration and microstructure, reducing porosity and improving mechanical properties. In this study, different nanoparticles have been used to reduce the porosity of mortars evaluating this improvement by means of electrical resistivity measurements. It is perfectly established the porosity reduction with the increasing of electrical resistivity. Reduction of porosity minimises the intake of aggressive agents into the mortar in a meaningful way, retarding the corrosion of metal reinforcement. Nanoparticles addition (<10%) within cement mortar have allowed to increase the electrical resistivity in up to 112% regarding to control sample, without modifying of mechanical properties.