René Gustus

Technische Universität Clausthal | TUC · Department of Energy Research and Physical Technologies

Due to the high specific surface area of titanium aluminide powders, significant and unavoidable surface oxidation takes place during processing. The resulting oxides disrupt the conventional powder metallurgical process route (pressing and sintering) by reducing green strength and sintered properties. Oxide-free particle surfaces offer the potenti...

Plasma in hydrogen-containing atmospheres is an efficient method for the reduction of iron oxides. Although a vast number of approaches were performed for the reduction of bulk Fe oxides with thermal hydrogen plasmas, there is almost no information about the non-thermal plasma reduction efficiency in the atmospheric pressure range. In the current a...

As oxygen negatively affects most production processes in the metalworking industry, a truly oxygen‐free production environment appears attractive in terms of the resulting material and component properties. This overview summarizes research conducted within the Collaborative Research Centre (CRC) 1368. The objectives of this CRC are twofold. First...

Alloy 36 (1.3912), also known as “Invar,” is an alloy with 36% nickel. The alloy has a remarkably low thermal expansion coefficient in certain temperature ranges. This peculiarity is called the invar effect, which was discovered in 1896 by the Swiss physicist Charles Édouard Guillaume Sahoo and Medicherla Mater today Proc 43:2242-2244, (2021). Ther...

The interaction of silane and water is discussed controversially in literature: some authors suggest monosilane and water react kinetically and sufficiently fast enough to remove water, while others state the reaction occurs only at elevated temperatures. This question is of technological interest for the removal of unavoidable water residues in Ar...

Conventional thermal spraying processes are almost exclusively carried out in an air atmosphere, resulting in the oxidation of the particle surfaces and interfaces within the coating and between the substrate and coating. Furthermore, the initial process of surface activation conventionally takes place in an air atmosphere, preventing an oxide-free...

Aluminium alloys, like AlMgSi1 and AlMg3, cannot be joined in industrial processes by laser beam brazing without the use of fluxes due to their resistant oxide layer. The aim of this study is to dispense with the use of flux. For the investigations, an oxygen-free atmosphere was created by using the highly reactive gas monosilane and thus achieving...

Laser beam brazing is an established manufacturing process due to its low heat input and esthetically appealing seams. However, brazing of materials with high oxygen affinity, such as aluminum alloys, requires the removal of surface oxides prior to the brazing process, commonly through the application of chemical fluxes that may be harmful to the e...

Conventionally, thermal spraying processes are almost exclusively carried out in an air atmosphere. This results in oxidation of the particles upon thermal spraying, and thus, the interfaces of the splats within the coating are oxidized as well. Hence, a full material bond strength cannot be established. To overcome this issue, a mixture of monosil...

We report on a new approach to transport samples for surface analysis safely from oxidation over long distances. The transport method is based on silane-doped inert gases, which are used as a transport medium. In this paper, we show that with the help of silane, highly purified inert gas atmospheres with oxygen contents of less than 10⁻¹⁵ mbar can...

The supply and processing of materials for highly stressed components are usually cost-intensive. Efforts to achieve cost and resource efficiency lead to more complex structures and contours. Additive manufacturing steps for component repair and production offer significant economic advantages. Machining needs to be coordinated with additive manufa...

Self-assembling films typically used for colloidal lithography have been applied to pine wood substrates to change the surface wettability. Therefore, monodisperse polystyrene (PS) spheres have been deposited onto a rough pine wood substrate via dip coating. The resulting PS sphere film resembled a polycrystalline face centered cubic (FCC)-like str...

Self-assembling films typically used for colloidal lithography have been applied to pine wood substrates to change the surface wettability. Therefore, monodisperse polystyrene (PS) spheres have been deposited onto a rough pine wood substrate via dip coating. The resulting PS sphere film resembled a polycrystalline FCC-like structure with typical do...

In the current study, the potential of dry machining of the titanium alloy Ti-6Al-4V with uncoated tungsten carbide solid endmills was explored. It is demonstrated that tribo-oxidation is the dominant wear mechanism, which can be suppressed by milling in an extreme high vacuum adequate (XHV) environment. The latter was realized by using a silane-do...

Ensuring a high adhesion of amorphous carbon films to steel substrates remains a challenging task, sustaining continuous research efforts to improve the adhesion strength. Besides the interlayer system and the substrate material, surface pretreatments have a significant impact on the adhesion behavior. Within this context, the influence of the High...

In the plastic-processing industry, the formation of unknown deposits at the interface between polymer melt and steel surfaces can pose major challenges, which occurs especially on screws, barrels, and tools. These deposits will detach during production and lead to quality restrictions mostly as spots in the products. We investigated the interactio...

The interfacial structure of ionic liquids (ILs) at electrode interfaces governs the performances in both charge transfer and mass transfer processes. A wide variety of studies using, for example, atomic force microscopy (AFM) and in situ scanning tunneling microscopy (STM), as well as X-ray reflectivity and the surface force apparatus (SFA), have...

A comparative study of the chemical reactions of three different ionic liquids prepared by physical vapor deposition on a Li/Cu surface was performed. In this investigation the ionic liquids 1-butyl-1-methylpyrrolidinium bis[fluorosulfonyl]imide ([Py1,4]FSI), 1-butyl-1-methylpyrrolidinium bis[trifluoromethylsulfonyl]imide ([Py1,4] TFSI) and 1-octyl...

Sodium-ion batteries (SIB) are emerging as potential stationary energy storage devices due to the abundance and cheap cost of sodium. A simple and energy efficient strategy to develop electrodes for SIB with a high charge/discharge rate is highly desirable. Here we demonstrate that by surface modification of Ge using electroless deposition in SbCl3...

Manganese(II) biphenyl-4,4'-dicarboxylate, prepared by crystallization of a mixture of biphenyl-4,4'dicarboxylic acid, manganese(II) chloride, and di(4-pyridyl) acetylene as base in a mixture of dimethylformamide, ethanol and water in a closed vessel at elevated temperatures forms a 3D network of {[Mn(bpdc)(H2O)(2)][Mn(bpdc)(H2O)]} containing one f...

Halbleiternanostrukturen der Gruppe III–V sind wichtige Materialien für optoelektronische Anwendungen und werden im Energiesektor erforscht. Ein einfacher Ansatz für die Synthese dieser Halbleiter mit klar strukturierten Nanostrukturen wird angestrebt. Die stromlose Abscheidung ist eine schnelle und vielseitige Methode für die Abscheidung eines Mat...

Group III-V semiconductor nanostructures are important materials in optoelectronic devices and are being researched in energy-related fields. A simple approach for the synthesis of these semiconductors with well-defined nanostructures is desired. Electroless deposition (galvanic displacement) is a fast and versatile technique for deposition of one...

The deposition behavior of bisphenol A polycarbonate (BPA-PC) on a Au(111) single crystal has been studied. Thin films of PC were prepared by in situ evaporation of PC pellets under UHV conditions. The resulting PC/Au(111) interfaces were characterized by means of Ultraviolet Photoelectron Spectroscopy (UPS), X-ray Photoelectron Spectroscopy (XPS)...

In this experimental investigation the interaction of lithium with 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([OMIm]Tf2N) is shown. For this purpose thin films of lithium and [OMIm]Tf2N were successively vapor deposited on a copper substrate and analyzed by X-ray Photoelectron Spectroscopy (XPS) as well as by Ultraviolet Photoel...

The highly ordered pyrolytic graphite (HOPG)/1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([OMIm]Tf2N) interface is examined by ultrahigh vacuum scanning tunneling microscopy (UHV-STM), atomic force microscopy (UHV-AFM) (and as a function of potential by in situ scanning tunneling microscopy (STM)), in situ atomic force microscopy...

In the present paper, the decomposition and the crystallization behaviour of amorphous Si2C films, which were deposited by r.f. magnetron co-sputtering on Si wafer substrates, are investigated. For analysis, the following methods were used: x-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), grazing incidence x-ray diffr...

Dielectric Barrier Discharge plasma treatment of a titanium metal foil in oxygen, nitrogen and air under atmospheric conditions is investigated employing X-Ray Photoelectron Spectroscopy (XPS). We investigated three different reference samples and compare the results with a large number of studies on the XPS analysis of titanium compounds containin...

The thermal stability of amorphous Si2C films was studied by means of X-ray Photoelectron Spectroscopy (XPS), Auger Electron Spectroscopy (AES), Grazing Incidence X-ray Diffractometry (GIXRD), Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). The films were deposited by magnetron sputtering onto silicon single crystals. The as-d...

The treatment of Titanium with different kinds of plasma is commonly used for etching, oxidation, carbonization or nitriding. During some of these techniques, a lot of heat is carried into the material, whereas others operate at room temperature. All of the processes reported so far have in common that cover gas is needed. The gas is choosen in ter...