Recent Activities in the Field of Thermal Barrier Coatings Including Burner Rig Testing in the European Union

Although thermal barrier coatings are used in industry for several decades there is still considerable demand for a further improvement of this coating system. Present research projects are for example dealing with the improvement of temperature capability and lifetime, developing of lifetime models, new processing technologies, or incorporating of additional functional properties in the coating. The present paper tries to give an overview on these recent research activities. In addition, it will also try to describe the different burner rig test facilities in Europe, which serve as an important test bed of thermal barrier coating systems.     

A Numerical and Experimental Investigation into Hot Stamping of Boron Alloyed Heat Treated Steels

Hot stamping of steel sheets using water or nitrogen cooling media was studied on a laboratory scale. Sheets of grade 22MnB5 boron steels in three different thicknesses were investigated and the results of experimental hot stamping tests were considered. Microstructural analysis, linear and surface hardness profiling as well as tensile tests of formed samples were carried out. After hot stamping, mostly fully martensitic microstructures, which yield ultra high strength levels, were produced. It is concluded that die cooling media, i.e., water or nitrogen, have a significant effect on material properties after hot stamping. Using liquid nitrogen as coolant in the punch instead of water increases yield strength by 50 to 65MPa. Moreover, the evolution of the temperature and force during the hot stamping process was simulated by using a coupled thermomechanical FEM program. The results of numerical simulation and experimental results are in good agreement.     

CFT30-用于6缸FWD车辆的链式CVT

CFT30是第一种将链传动应用于前置（横置）前驱、并配备有提高起步性能的变矩器的CVT。变速器能够传递现代6缸发动机310Nm的转矩。它采用全电子控制,比目前常用的4速自动变速器及刚开发出来的6速自动变速器性能更好、油耗更低。完美的换档感觉提高了驾驶舒适性。本文介绍了变速器系统、设计和主要部件。对CFT30如何解决燃油经济性、性能和舒适性作了详细的解释。同时给出了重要的部件试验和车辆试验结果。     

Structural engineering of nanoporous anodic aluminium oxide by pulse anodization of aluminium

Nanoporous anodic aluminium oxide has traditionally been made in one of two ways: mild anodization or hard anodization. The first method produces self-ordered pore structures, but it is slow and only works for a narrow range of processing conditions; the second method, which is widely used in the aluminium industry, is faster, but it produces films with disordered pore structures. Here we report a novel approach termed "pulse anodization" that combines the advantages of the mild and hard anodization processes. By designing the pulse sequences it is possible to control both the composition and pore structure of the anodic aluminium oxide films while maintaining high throughput. We use pulse anodization to delaminate a single as-prepared anodic film into a stack of well-defined nanoporous alumina membrane sheets, and also to fabricate novel three-dimensional nanostructures.     

Specific features of the current–voltage characteristics of SiO2/4H-SiC MIS structures with phosphorus implanted into silicon carbide

The effect of phosphorus implantation into a 4H-SiC epitaxial layer immediately before the thermal growth of a gate insulator in an atmosphere of dry oxygen on the reliability of the gate insulator is studied. It is found that, together with passivating surface states, the introduction of phosphorus ions leads to insignificant weakening of the dielectric breakdown field and to a decrease in the height of the energy barrier between silicon carbide and the insulator, which is due to the presence of phosphorus atoms at the 4H-SiC/SiO₂ interface and in the bulk of silicon dioxide.     

Geometry-adapted hexahedral meshes improve accuracy of finite-element-method-based EEG source analysis

Mesh generation in finite-element- (FE) method-based electroencephalography (EEG) source analysis generally influences greatly the accuracy of the results. It is thus important to determine a meshing strategy well adopted to achieve both acceptable accuracy for potential distributions and reasonable computation times and memory usage. In this paper, we propose to achieve this goal by smoothing regular hexahedral finite elements at material interfaces using a node-shift approach. We first present the underlying theory for two different techniques for modeling a current dipole in FE volume conductors, a subtraction and a direct potential method. We then evaluate regular and smoothed elements in a four-layer sphere model for both potential approaches and compare their accuracy. We finally compute and visualize potential distributions for a tangentially and a radially oriented source in the somatosensory cortex in regular and geometry-adapted three-compartment hexahedra FE volume conductor models of the human head using both the subtraction and the direct potential method. On the average, node-shifting reduces both topography and magnitude errors by more than a factor of 2 for tangential and 1.5 for radial sources for both potential approaches. Nevertheless, node-shifting has to be carried out with caution for sources located within or close to irregular hexahedra, because especially for the subtraction method extreme deformations might lead to larger overall errors. With regard to realistic volume conductor modeling, node-shifted hexahedra should thus be used for the skin and skull compartments while we would not recommend deforming elements at the grey and white matter surfaces.     

Stabilization of an optical microscope to 0.1 nm in three dimensions

Mechanical drift is a long-standing problem in optical microscopy that occurs in all three dimensions. This drift increasingly limits the resolution of advanced surface-coupled, single-molecule experiments. We overcame this drift and achieved atomic-scale stabilization (0.1 nm) of an optical microscope in 3D. This was accomplished by measuring the position of a fiducial mark coupled to the microscope cover slip using back-focal-plane (BFP) detection and correcting for the drift using a piezoelectric stage. Several significant factors contributed to this experimental realization, including (i) dramatically reducing the low frequency noise in BFP detection, (ii) increasing the sensitivity of BFP detection to vertical motion, and (iii) fabricating a regular array of nanometer-sized fiducial marks that were firmly coupled to the cover slip. With these improvements, we achieved short-term (1 s) stabilities of 0.11, 0.10, and 0.09 nm (rms) and long-term (100 s) stabilities of 0.17, 0.12, and 0.35 nm (rms) in x, y, and z, respectively, as measured by an independent detection laser.