Page 11 - Research and innovation In advanced materials with application to the railway sector

or graphite. These studies can be extended to consider variables such as the degree of
humidity or salinity, or the parameters of the thermomechanical treatments of copper. In
addition, as alternatives to electrolytic copper (ETP), new alloys have been developed with
higher recrystallization temperatures and better mechanical properties, which provide
greater resistance to wear and low creep. Less wear results in lower maintenance costs and
a higher annealing temperature, an increase in the ability of the wire to withstand current
peaks.

V. CHALLENGES AND RECOMMENDATIONS

If in the year 2015 it was stated the need for the sector to consolidate its competitive
advantage over other means of transport, in terms of efficiency, sustainability, punctuality,
service and passenger comfort, as of 2021 this reflection is still fully valid. The need for R +
D +I in order to continue improving circulation speeds, construction and operating costs,
maintenance, environmental impact and sustainability is still valid. The development and
improvement of materials is, and will continue to be, a fundamental chapter of R+D+I in the
sector.

Among the sections that are identified as lines in which to work, it is important to highlight
the entire field of multifunctionality, hybrid materials, metamaterials and functional
coatings, to achieve improvements in vibrations, noise and comfort, corrosion and stray
currents, improvement of behaviour at low temperatures and integration of antifreeze
functions. Also, omniphobic coatings, applicable on composites or metals, to repel all types
of liquids / solids, or to achieve more hygienic surfaces, repel viruses and bacteria. The
objective is to make the integration of solutions possible in the final product without losing
efficiency; and start industrial manufacturing at a reasonable cost.

In the field of rail, it is necessary to continue highlighting the importance of improving the
possible alloys and treatments, to improve their wear conditions, and digitization -Internet
of Steel- with the integration of sensors focused on monitoring and maintenance.

In the field of railway installations and electrification, the projection of superconducting
materials stands out, especially magnesium diboride and second-generation high-
temperature superconductors. Due to their practically zero resistance in DC current, they
allow the transmission of high powers without voltage drops and without the need to
increase the line voltage level. For this reason, they are applicable in substations or in DC
traction systems, favouring regenerative braking for energy recovery. In addition, they can
enable greater effective distances between substations and fast charging systems, among
other applications.

In the section on lightweighting by means of advanced composite materials, and despite the
work carried out in recent years on fire-resistant composites, there is still a long way to go
in incorporating a greater number of solutions that are compatible with EN 45545-2 and
that allow greater production volume, more industrial manufacturing processes, with
production systems more adapted to the needs of the sector and a lower cost of the
manufactured components. In this way, composites based on epoxy matrices, benzoxacin
or hybrid chemistry will be able to substitute metals in structural or interior parts. At the
same time, other materials such as polycarbonates may replace the use of glass and other

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Position paper: Research and innovation in advanced materials with application to the railway sector
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