Universität des Saarlandes
The European plan for the transition to a circular economy (CE) has
the goal of rethinking resource efficiency and materials flows, offering a
life-cycle view and being the sustainable design of products in the production
sector one of the key points in the proper implementation of CE [1]. However, the current practices
related to its implementation are mainly focused from the end-of-life
perspective, especially the development and optimization of recycling processes.
The Eco-Design Directive[2] includes the implementation of
strategies such as selection of low impact materials, reduction of materials
usage, optimization of production techniques, reducing the impact during use,
and
optimization of initial lifetime, among others. Those strategies enforce the
principles advocated by Cooper of durability and optimized energy and material
consumption [3].
Proper material selection is a prerequisite for the eco-design of
products and is directly related to the design strategies for slowing and
closing the loop in a CE context. Slow
the loop strategies include slowing material flows in each phase of the
life cycle such as, design for durability and product life extension. In this
context, materials science acts as a crucial link between different eco-design
strategies, since it can provide the necessary knowledge and material’s
technology for the proper material’s selection for the design and production of
engineering components with an extended service life. This will consequently
result in the reduction of material demand and energy consumption.
Energy loss due to friction and wear (i.e., tribological contacts)
were estimated to be larger than 20% of the global energy consumption. They could potentially be reduced
by about 40% as result of new materials, improved surfaces, and better
lubrication technologies [4]. In the last two decades, a new
tribology subdiscipline (Green Tribology)
has been developed which supports the preservation of resources, energy, and
material criticality [5,6].
This
work has the objective of conceptualizing new or enhanced materials with improved
performance that will result in products and components with an extended
service life and improved ecological compatibility. In particular, the
development of material systems with reduced friction and wear that positively influence
the decision making during product and component design. Based on that, the
current work highlights promising results obtained on the use of carbon
nanoparticles (e.g., carbon nanotubes, carbon onions, nanodiamonds, etc.) as the
main component in the fabrication of protective and low-friction coatings, and
metal matrix composites (MMC) with self-lubricating characteristics [7–10]. Furthermore, the combination of a
chemistry-free process (laser interference patterning) with carbon-nanotube coatings
showed a three-fold friction reduction in comparison to a benchmark (untextured/uncoated)
system [11]. Finally, improved self-lubricating effects are
obtained by combining self-lubricating MMC with an optimized solid-lubricant
coating and a periodically-structured surface, resulting in a system with
4-fold reduced coefficient of friction and 115-fold wear reduction compared to
a reference state.
Abstract
Erwerben Sie einen Zugang, um dieses Dokument anzusehen.
© 2026