Magnesium alloys present an alternative to medical cases in which polymeric sutures may not be ideal. To date, no efficient and low‐cost manufacturing process for the fabrication of magnesium‐based sutures can be found. To obtain an alternative, the previously characterised magnesium alloys ZEK100 (98% Mg), AX30 (96.2% Mg), AL36 (91% Mg) and MgCa0.8 (99.2% Mg) were cast, extruded into 30 mm diameter bars and extruded into 0.5 mm diameter wires. To determine the mechanical properties of the wires, grain size measurements, tensile tests as well as qualitative bending tests were carried out. The ZEK100 alloy's wires showed the finest microstructure having grains of 1.2 µm in diameter. Coarser microstructures were observed for MgCa0.8, AX30 and AL36. The alloy ZEK100 had the highest tensile stress (367 MPa) also revealing a brittle behaviour due to its fine microstructure. The tensile test, carried out for AX30 as well as AL36, resulted in comparable high fracture strains (10.6%) and tensile stresses (300 MPa). However, MgCa0.8 showed a tensile strength of 315 MPa and a low strain of 1.6%. Within the qualitative bending test wires made of the alloy AL36 were able to form tight knots, which is a key feature for suture applications. The comparison of the magnesium sutures with commercially available polymeric sutures revealed lower strength and elongation for the magnesium alloys. Yet, the wires exhibited mechanical properties that can meet the requirements of a suture material.

High-pressure die compound casting relies on high bond quality, and high thermal contact conductance at the interface is a key issue in the context of cast advanced cooling components, such as lightweight heat sinks for desktop and portable computers. The current study aims at enhancing the thermal contact between a copper insert piece and an AlSi9Cu3(Fe) cast alloy by developing suitable Zn-based coatings, which are used to establish a firm metallurgical bond between the solid insert and the cast alloy during highpressure die-casting. It is demonstrated by microstructural analyses that various phases form at the interfaces in the casting process. As the thermal conductivities of these phases have not been available, these are determined individually using a thermoflash device. The SEM investigations indicate that mainly ternary phases of the type Al x Cu y Zn z emerge in the bonding zone, as the high casting temperatures promote the diffusion of aluminum atoms into the coating. Interestingly, an alloy containing 50 wt% zinc reaches a thermal conductivity as high as 166 W mK À1 . The microstructural characteristic at the interfaces and the ramifications with respect to applications are discussed.

The global efforts on CO2 emission reduction reflect the importance of a change in personal mobility. Nowadays there is a need in the automotive sector to focus more and more on ecological energy sources. One key to approach this intention is to transfer the modular manufacturing, as known in the conventional car design, to the design of electric powered vehicles. Taking into account that renewable energy sources, for example hydrogen, green electric power or fuel produced out of plants, are able to be combined with an electrical drivetrain, which is able to handle all of them in once. The impressive opportunity is that all those energy sources have a commonality. All of them can be used to produce electrical power onboard. The easiest way seems to be the storage of electrical power in rechargeable batteries; however there are various different options. Hydrogen can be utilized in a fuel cell to produce electrical power and every hydrocarbon fuel can also be used to power a fuel cell in combination with a previous steam reformation. Considering hydrocarbon fuel, there is further the alternative to burn it in combustion engines and to combine it with a generator. The perspective of this short excursus is that it does not depend on the chosen energy resource, because there is always the option to use the energy, to power an electrical drivetrain. This assumption leads to the encouragement to develop a modular and scalable electric driven axle, which is easily adaptable to ensure a compatibility with a brought field of vehicles.

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