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Previous studies have shown that dosing AdBlue into the exhaust system of diesel engines to reduce nitrogen oxides can lead to an increase in the number of particles (PN). In addition to the influencing factors of exhaust gas temperature, exhaust gas mass flow and dosing quantity, the dosed medium itself (AdBlue) is not considered as a possible influence due to its regulation in ISO standard 22241. However, as the standard specifies limit value ranges for the individual regulated properties and components for newly sold AdBlue, in reality there is still some margin in the composition. This paper investigates the particle number increase due to AdBlue dosing using several CPCs. The increase in PN is determined by measuring the number of particles after DPF and thus directly before dosing as well as tailpipe. Several AdBlue products from different sources and countries are measured and their composition is also analyzed with regard to the limit values regulated in the standard.

When using "green" hydrogen, fuel cell technology plays a key role in emission-free mobility. A powertrain based on fuel cells (FC) shows its advantages over battery-electric powertrains when the requirement profile primarily demands high performance over a longer period of time, high flexible availability and short refueling times. In addition, FC achieves higher effi-ciencies than the combustion of hydrogen in a gas engine, meaning that the chemical energy is used more efficiently than with established combustion engines. When using FC technology, numerous companies in Baden-Württemberg can contribute their specific expertise from the traditional automotive construction and supplier business. This includes auxiliary units in the air (cathode) and hydrogen (anode) path, such as the air compressor, the H2 recycling pump, humidifier, cooling system, power electronics, valve and pressure tank technology as well as components of the fuel cell stack itself.

Gas bearings are an effective solution to high-speed rotor applications for its contamination free, reduced maintenance and higher reliability. However, low viscosity of gas leads to lower dynamic stiffness and damping characteristics resulting in low load carrying capacity and instability at higher speeds. Gas bearings can be enhanced by adding a foil structure commonly known as gas foil bearings (GFBs), whose dynamic stiffness can be tailored by modifying the geometry and the material properties resulting in better stability and higher load carrying capacity. A detailed study is required to assess the performance of high-speed rotor systems supported on GFBs, therefore in this study a bump type GFB is analyzed for its static and dynamic characteristics. The static characteristics are obtained by solving the non-linear Reynolds equation through an iterative procedure.

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This specification covers a magnesium alloy in the form of sheet and plate from 0.016 to 3.000 inches (0.41 to 76.20 mm), inclusive, in thickness (see 8.5).

This specification covers a magnesium alloy in the form of extruded bars, rods, wire, tubing, and profiles up to 40 square inches (258 cm2) in cross-sectional area (solids) and up to 8.5 inches (216 mm) OD by 1.188 inches (30.18 mm) wall thickness (tubing) (see 8.5).

This specification covers unalloyed copper in the form of sheet, strip, and plate at least 0.015 inch (0.38 mm) in nominal thickness.

This specification covers an aluminum alloy in the form of extruded rods, bars, and profiles (shapes) 0.040 to 1.500 inches (1.02 to 38.10 mm), inclusive, in thickness, and produced with maximum cross-sectional area of 23.25 square inches (15000 mm2) and a maximum circumscribing circle diameter (circle size) of 15.5 inches (394 mm) (see 2.4.1 and 8.6).

This specification covers an aluminum alloy in the form of sheet 0.020 to 0.128 inch (0.51 to 3.25 mm), inclusive, in nominal thickness (see 8.5).

This specification covers an aluminum alloy in the form of plate 1.000 to 6.000 inches (25.40 to 152.40 mm), inclusive, in nominal thickness (see 8.5).

This specification covers an aluminum alloy in the form of alclad sheet and plate supplied in the -T861 temper.

This specification covers an aluminum alloy in the form of alclad coiled sheet from 0.010 to 0.128 inch (0.25 to 3.25 mm), inclusive, in thickness supplied in the -T4 temper (see 8.5).

This specification covers a titanium alloy in the form of welding wire (see 8.5).

This specification covers a titanium alloy in the form of bars, forgings, and flash-welded rings up through 12.000 inches (304.80 mm), inclusive, in diameter or least distance between parallel sides, and stock of any size for forging or flash-welded rings. Bars, forgings, and flash-welded rings with a nominal thickness of 3.000 inches (79.20 mm) or greater shall have a maximum cross-sectional area of 113 square inches (729 cm2) (see 8.5).

This specification covers a titanium alloy in the form of bars up through 4.000 inches (101.60 mm) in nominal diameter or least distance between parallel sides, inclusive, forgings of thickness up through 4.000 inches (101.60 mm), inclusive, with bars and forgings having a maximum cross-sectional area of 32 square inches (204.46 cm2), and stock for forging of any size (see 8.6).

Abstract This study aims to explore the wear characteristics of fused deposition modeling (FDM) printed automotive parts and techniques to improve wear performance. The surface roughness of the parts printed from this widely used additive manufacturing technology requires more attention to reduce surface roughness further and subsequently the mechanical strength of the printed geometries. The main aspect of this study is to examine the effect of process parameters and annealing on the surface roughness and the wear rate of FDM printed acrylonitrile butadiene styrene (ABS) parts to diminish the issue mentioned above. American Society for Testing and Materials (ASTM) G99 specified test specimens were fabricated for the investigations. The parameters considered in this study were nozzle temperature, infill density, printing velocity, and top/bottom pattern.

Abstract AISI H13 hot work tool steel is commonly used for applications such as hot forging and hot extrusion in mechanical working operations that face thermal and mechanical stress fluctuations, leading to premature failures. Cryogenic treatment was applied for AISI H13 steel to improve the surface hardness and thereby fatigue resistance. This work involves failure analysis of H13 steel specimens subjected to cryogenic treatment and gas nitriding. The specimens were heated to 1020°C, oil quenched followed by double tempering at 550°C for 2 h, and subsequently, deep cryogenically treated at −185°C in the cryochamber. Gas nitriding was carried out for 24 h at 500°C for 200 μm case depth in NH3 surroundings. The specimens were subjected to rotating bending fatigue at constant amplitude loading at room temperature.