EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Recent work indicates that HVOF thermal spraying WC-Co coatings have been used to enhance the wear resistance of various engineering components in a variety of industrial environments. In the present work WC-Co powder containing Cr particles in an amount of 10% was deposited on ductile cast iron with high velocity oxy-fuel (HVOF) thermal spray coating technique. An investigation was conducted...

Effective surface pretreatment is the key to long-term stable and durable bonds between different materials, e.g., used in structural bonding and coatings. Its purpose, besides a general cleaning of a joint surface, is to structure and functionalise the interface. Particularly attractive and fast, laser surface pretreatment enables simple, reproducible and waste-free processing of surfaces of...

The development of carbon nanotubes (CNTs)-reinforced metal matrix composites (MMCs) is challenged by the production of a homogeneous distribution of CNTs in the metal matrix and the formation of a good interface between the CNTs and the matrix. Therefore, we propose that surface modification of CNTs with a coating material such as silicon carbide that is thermally stable and wettable by the...

One of the promising methods of microstructure modification in surface layers is a friction stir processing (FSP). This method is based on the basic principles of friction stir welding technology (FSW) however, the FSP method, unlike FSW, is used to modify the microstructure of the materials, and not to join metal elements. The process consists in heating and plasticizing the material as a...

Magnesium silicide and titanium suboxides (TiOx) are considered promising thermoelectric materials to generate electricity from waste-heat thanks to their thermoelectric performance, low-cost, low-toxicity and light-weight. Nevertheless, the stability and oxidation resistance over time at temperatures higher than 500° C for Mg-silicide and 400°C for TiOx respectively, are critical issues....

To improve the performance and efficiency of combustion engines, higher operating temperatures are required. Commonly used high temperature structural materials (e.g. Ni-base) reach their limitations beyond 1100 °C.

Refractory metals are promising substitutes due to their high melting point and their good mechanical properties at high temperatures. One major drawback of most of these metals...

Since their first mentioning in the early 2000s, the interest in high entropy alloys (HEA) as a new material class has been ever increasing. Starting with bulk materials, also thin films gained attention in the past years due to the wider flexibility in the available synthesis methods and attainable growth conditions. Among the different HEAs, alloys mainly comprising refractory metals,...

The nowadays requirements for high-performance materials in aerospace industry pose a challenge in terms of their tooling and machining. A promising way to reduce the wear of cutting tools, thereby extending their lifetimes, is represented by the application of self-lubricating nanocomposite coatings. It has been recently shown that Ag nanoparticles dispersed in a superhard TiSiN matrix are...

Spark Plasma Sintering (SPS) is a powder metallurgy technique used for the elaboration of dense materials with a fine-grained microstructure [1]. In this process, a pulsed electric current and a uniaxial pressure are applied simultaneously, leading to high heating and cooling rates, thus limiting the grain growth [2]. The powder is placed into a graphite die and the pressure is applied by two...

Electrodeposited chromium coatings exhibit high hardness, good wear resistance and corrosion resistance . Development of electrodeposited trivalent chromium coating Cr(III) baths becomes a new challenge for replacing the conventional Cr(VI) baths due to the hazardous character of hexavalent chromium salts. Several Cr(III) electrolytes were developed in the past , but the optimization of the...

Alternative barrier layers have been considered to replace Ta/TaN, such as Ru and Co-based binary systems, e.g. Ru W, Ru-Mn, and Co W, in Cu interconnect metallization. The Co-W system is an interesting candidate to novel barrier materials due to its electrical and thermal properties. Co-W can function as both, the diffusion barrier and the seed layer whereon Cu can be directly electroplated,...

The present work focuses on the fabrication and characterization of hard anodizing (HA) and plasma electrolytic oxidation (PEO) coatings on an Al10Si1Mg alloy manufactured via direct metal laser sintering (DMLS). The coatings were fabricated on both XY and XZ directions of the DMLS alloy. A A361 cast alloy was also treated for comparison. The hardness (H) and elastic modulus (E) of the...

Motor neuron diseases like Parkinson’s can induce severe tremors in later stages, which seriously impair the daily life of elderly patients, particularly when drug-based treatments have ceased to work. A possible way to improve the patients’ quality of life is deep brain stimulation (DBS) treatments. Here, platinum neural electrodes are implanted into the brain, providing electric pulses to...

Additively manufactured (AM) porous metal and polymer materials were coated using thermal and plasma-enhanced (PE) Atomic Layer deposition (ALD). Structures were plates, lattice cells with a mesh size between 0.5 and 1.5 mm and random porous with a pore size between 1 and 2 mm. Applied AM methods were laser-beam powder-bed fusion (LB-PBF), material extrusion bonded by thermal reaction...

A recent study suggests about 20 % of the consumed energy worldwide is related to friction and 18 % of this energy can be saved. Carbon alloyed transition metal dichalcogenide coatings present a tremendous potential in domains where friction reduction is aimed. They possess exquisitely low friction coefficients in diverse environments and can self-adapt to a variety of sliding conditions. In...

Owing to their advantageous properties such as a high hardness and good oxidation resistance, Ti(Al)SiN protective hard coatings can be used for metal cutting applications. Within this work, the microstructure of arc evaporated TiN, TiSiN and TiAlSiN coatings with low Al contents of 3 and 14 at.% was correlated with their mechanical properties. X-ray diffraction (XRD) as well as scanning...

Functional coatings (thin films and multilayers) are widely applied in technological applications due to the tunability of their mechanical, thermal, optical and electro-magnetical properties. An important factor which affects their reliability in applications, is the intrinsic stress generated during the deposition process, which can determine unwanted effects as cracking, peeling, and as...

In the recent years, a shift from rigid to flexible electronics was observed where the latter enables new degrees of freedom in the design of consumer products like displays, wearable sensors, solar cells, among others. Unlike in rigid electronics, thin film materials used in flexible electronics are deposited on thin compliant polymer substrates and they have to withstand various static and...

Hydrogen-free amorphous carbon films gain increasing importance as wear resistant protective coatings in high-wear applications and are in industrial use on cutting tools and sliding components, especially in the automotive industry. Despite the broad use of these coatings in many applications due to their extremely high hardness, they reach their limits in applications with locally very high...

Increasing demands in environmental protection and environmentally friendly solutions are important market drivers for the development of sustainable chemicals. Chromium (VI) is used in electroplating technology to pretreat polymers in order to achieve good metallization. However, it´s applications of now require special permits. This is an EU strategy to prevent the use of dangerous and...

Antisoiling technologies, based on easy-to-clean and self-cleaning coatings have received significant interest in research and commercial applications. For outdoor uses, easy-to-clean hydrophobic coatings have perhaps bigger potential since the major portion of atmospheric pollution is inorganic. On the other hand, hydrophilic self-cleaning coating usually exhibit strong antistatic functions,...

The European Commission estimates that 450GW of offshore wind power is required to keep temperature rises below 1.5°C. To achieve this goal by 2050, the ongoing scientific and technological challenges on wind turbines must be met. Specifically, ice accumulation on turbine blades still stands a major operational issue for wind energy plants. Excessive ice mass on the blades lead to damage or...

One of the main problems of the injection process is the demolding stage because polymers frequently remain adhered to the mold surface, producing defective polymeric parts and reducing the mold lifetime [1, 2].
In the present work, alumina (Al2O3) and titanium dioxide (TiO2) thin films were deposited by atomic layer deposition (ALD) technique on steel substrates. The superficial chemical...

Organosilanes are well known for their application as coupling agents and surface modifiers as used in anti-adhesive coatings, self-cleaning surfaces and separation layers. The wide range of available organosilanes enables a precise adjustment of the properties of the coating to meet individual requirements. Our previous studies demonstrated that perfluorinated organosilanes (based on mono-...

According to World Health Organization (WHO), diabetes will be the seventh cause of death by 2030. One of the main problems of the disease is related to the Diabetic Foot (DF) pathology. The DF defines various injuries that can occur on the foot of the diabetic patients and can lead to lower extremity amputation. One way to prevent the risk of foot injury is to use adequate footwear to avoid...

Implant surfaces with cytocompatible and antibacterial properties are extremely desirable for the prevention of implant’s infection and the promotion of osseointegration. In this work, both micro-arc oxidation (MAO) and DC magnetron sputtering techniques were combined in order to endow tantalum-based surfaces with osteoblastic cytocompatibility and antibacterial activity. Porous Ta2O5 layers...

Implant-associated infections are a crucial issue for the failure of medical treatments which leads economic and social associated costs. Bacterial adhesion and biofilm formation are important steps for the development of implant-related infections. Titanium-base bulk metallic glasses (BMGs) have attracted much attention for future medical applications such as orthopedic implants for...

In the last decades, mobile miniaturized devices have attracted an increasing interest due to their great potential in a broad range of applications. Untethered microrobots would allow less invasive surgery, precise cell manipulation and efficient drug delivery [1]. In this context, artificial bacterial flagella (ABF) are highly attractive due to their precise magnetic control. One of the most...

Fe-Mn-C alloys show unique mechanical properties making them a promising candidate to fabricate thin biodegradable cardiovascular stents [1]. However, compared with the conventional Co-Cr stents, these alloys have low radio-visibility under X-ray imaging, and this can impede their visualization during the clinical implantation, and the follow-up procedures [2][3]. Currently, tantalum markers...

The unique microstructures of nanoscale coatings are the reason for their superior properties in wear applications like cutting tools. By using chemical vapor deposition (CVD) a nano-lamellar AlTiN coating consisting of TiN and AlN was achieved by spontaneous self-organization during layer growth. These results suggested the investigation of the AlZrN system.
In this study, AlZrN coatings...

The ever-increasing demands for longer tool life in high-speed machining require multifunctional coatings that display several interlinked characteristics such as high thermal stability, hot hardness and toughness. For this purpose, hard nitride (Ti, Al)N-based nanocomposites coatings have been developed [1–3], but they still suffer from low fracture resistance. In this work, a series of high...

Metastable solid materials such as amorphous or nanocrystalline alloys, supersaturated solid solutions, high-temperature or high-pressure phases persisting at normal conditions, have been of great interest due to a possibility to explore novel structures with unknown properties. These materials are kinetically determined and can be therefore synthesize only by non-equilibrium processes....

Soiling of mirrors is one of the main reasons for the increase of maintenance costs in concentrated solar thermal power (CSP) generation ([Bellman, 2020][1]). Such a problem poses multiple challenges originating both from the surfaces' nature and their  interaction with their environment - such as desert dust - which previous approaches have failed to address fully. For this application the...

Since the 60’s, the interest of the scientific community for metallic glasses (MGs) has increased considerably. Thanks to their amorphous structure, they display intrinsic chemical homogeneity combined with a lack of crystallographic defects, leading to unique characteristics in comparison with conventional polycrystalline materials. Bulk MGs are synthetized from a fast quenching (which...