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Mn+1AXn (MAX) phases are novel structural and functional materials with a layered crystal structure. Their unique properties such as good machinability, high electrical conductivity, low friction, and corrosion resistance are appealing for many engineering applications. Herein, Ti2AlC and Ti3AlC2 MAX thin films are synthesized by magnetron sputtering and subsequent thermal annealing. A multilayer approach is used to deposit single‐element nanolayers of titanium, aluminum, and carbon onto silicon substrates with a double‐layer‐diffusion barrier of SiO2 and SixNy. Ti2AlC and Ti3AlC2 thin films (thickness ≈500 nm) are formed via rapid thermal annealing and verified by X‐Ray diffraction. Nanoindentation tests show hardness values of about 11.6 and 5.3 GPa for Ti2AlC and Ti3AlC2, respectively. The tribological behavior of the Ti2AlC and Ti3AlC2 thin films against AISI 52100 steel balls under dry sliding conditions is studied using ball‐on‐flat tribometry. The resulting coefficient of friction (CoF) for Ti2AlC and Ti3AlC2 ranges between 0.21–0.42 and 0.64–0.91, respectively. The better tribological behavior observed for Ti2AlC thin films is ascribed to its smaller grain size, reduced surface roughness, and higher hardness. [ABSTRACT FROM AUTHOR]

Cold-joined connectors (CJC) are widely used, owing to the simplicity of the assembly process, the low initial investment, and the possibility to join several contacts in parallel. Due to the fast-growing number of high power applications in the automotive industry, increasing efforts are made in order to make these advantages of the cold joining technology (CJT) suitable for high currents. New finite element method (FEM) models are still developed for supporting the new design cycle. The preferred technology to produce the assembly parts for high current CJC is die-cutting. Two punched edges will come in contact during the joining process to form a high power connector (HPC). Therefore, accurately describing the material properties at punched edges is crucial for a correct understanding and finite element (FE) modeling of the cold-joining process (CJP). Die-cutting causes a strong strain hardening in the contact zone and changes the material properties significantly. Thus, the material properties of the bulk material cannot be assumed at punched edges for the FE-simulation. This paper presents a new method for an improved material description of punched edges. The hardening mechanisms caused by die-cutting are studied by means of electron backscatter diffraction (EBSD) and quantified with nanoindentation experiments. The hardness distributions at punched edges are correlated to flow curves, building a new inhomogeneous material law for the cold-joining simulation. The new material description is validated by means of a small-punch test on a real assembly part and shows a significant improvement of the component's material characterization. [ABSTRACT FROM AUTHOR]

MAX phase coating could have interesting technical applications in many fields. This paper describes the synthesis of the M n+1AX n phase Ti3SiC2 by a rapid thermal annealing process of physical vapor deposited TiCSi multilayer thin films on Si (100) and SiO2 substrates. Annealing temperatures of 800-1000 °C affected the solid state reaction of titanium, carbon and silicon creating titanium-carbides, -silicides, and Ti3SiC2. The film structures and chemical compositions were observed by grazing incidence X-ray diffraction, transmission electron microscopy, and glow discharge optical emission spectroscopy. Analysis after the rapid thermal processing revealed the formation of the polycrystalline M n+1AX n phase Ti3SiC2 in coexistence with TiSi2, TiC and Ti5Si3, even within a 0 s annealing process. This synthesis method has a high potential for the formation of MAX phases as a high temperature electrical contact material. [ABSTRACT FROM AUTHOR]