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Dynamic interaction between railway car and track on a switch and a crossing of a standard turnout is considered. Wheel/rail forces and vehicle motion for nominal track geometric parameters and the influence of the selected parameters deviations on the system dynamic behaviour are considered. Results of computer simulations were compared to proper measurements of wheel/rail lateral and vertical forces during the turnout passage. They imply a conclusion that specific turnout parameters and analysed deviations of some of them create a vital cause of the dynamic interaction growth between vehicle and track. For the covering abstract see ITRD E117109.

Measuring slow crack propagation data in small slices of brittle materials, elongations were cemented to both sides giving a four-point bend specimen. A method of introducing a definite sharp crack was employed to enable displacement-controlled fracture experiments to be performed. For the evaluation of the load-displacement plots of controlled fracture experiments an experimental compliance calibration was done for measuring crack length from compliance. The method to determine the curve of crack resistance against crack velocity was tested with window glass, giving good agreement between measurements on homogeneous and cemented specimens, if internal stresses from preparation are negligible.

Aus zwei Edelmetall-Aufbrennlegierungen und zwei keramischen Massen der Dentaltechnik wurden Metall-Keramik-Schichtverbundproben hergestellt, wobei bei einem Teil der Proben zusatzlich eine goldreiche Schicht zwischen die Verbundpartner eingebracht wurde. Die mikroskopische Untersuchung zeigte, das sich metallseitig an der Grenzflache unedle Legierungsbestandteile angereichert hatten und keramikseitig eine flachenhafte Zone erhohter Porositat (etwa 5–15%) gebildet wurde. Die in der Grenzflache mit einem Spitzkerb versehenen Proben wurden im Vierpunktbiegeversuch bei Raumtemperatur kontrolliert gebrochen. Der Ris verlief zumindest teilweise in der grenzflachennahen, porosen Zone der Keramik, so das der mittlere Riswiderstand R der Grenzflache bestimmt werden konnte. Fur Proben ohne goldreiche Zwischenschicht lag R zwischen 3 und 12 J/m2 und damit in der Regel niedriger als in der Keramik (etwa 12 J/m2). Die relativ grose Streuung wird vorwiegend auf herstellungsbedingte innere Spannungen zuruckgefuhrt. Fur die hohen R-Werte der Proben mit goldreicher Zwischenschicht (bis 36 J/m2) wird die gute Verzahnung zwischen Metall und Keramik als ursachlich angesehen. Characterisation of Adherence of Precious Alloy to Dental Ceramic Laminated metal-ceramic composites were produced from two Aubase alloys and two ceramic powders. For part of the specimen an extra Aurich layer was brought into the metal-ceramic interface. Microscopic investigations showed enrichment of non precious alloying elements in the metallic region adjacent to the interface and a sheet of enhanced porosity (about 5–15%) in the ceramic region adjacent to the interface. After producing a Chevron notch in the interface the composite specimens were fractured in a controlled mode in four point bending. As the crack was at least partly running along the ceramic zone of enhanced porosity near the interface, the average crack resistance R of the interface could be determined. In specimens without an extra Au-rich layer R was between 3 and 12 J/m2 and thus less than the R-value of the ceramic (R 12 J/m2). The relatively large scatter is supposed to be mainly due to internal stresses. Specimens containing an extra Au-rich layer showed high R-values (up to 36 J/m2) due to good interlocking of metal and ceramic.

Tests were made with a pair of Ekman current meters to observe the effect of ship's roll upon their measurements and their behavior. In calm seaways where the current speed ranged from five to 45 cm/sec the speeds indicated by the two instruments were consistent within five per cent, and the indicated directions were within four degrees. In weaker currents the direction difference is twice as large. When the sea/swell conditions became greater than 1/1 the scatter in the indicated speeds became greater than ten per cent, and the results were considered unusable. Directions were measured within an accuracy of ten degrees in sea/swell as great as 2/3. One instrument was given an oscillation approximating a movement caused by a ship's roll of 10 to 15°. Its recorded speeds were 1.5 times those measured by a stationary one. This increase is due to the excess revolutions made by the propeller of the oscillating instrument during its downward swing. The increase in the scatter of the speed differences of the two instruments during sea/swell > 1/1 is attributed to this also. There was no appreciable variation in the directions during this artificial roll except when measurements were made in weak currents.