Although secondary data analyses have been established in recent years in health research, explicit recommendations for standardized, transparent and complete reporting of secondary data analyses do not exist as yet. Therefore, between 2009 and 2014, a first proposal for a specific reporting standard for secondary data analysis was developed (STROSA 1). Parallel to this national process in Germany, an international reporting standard for routine data analysis was initiated in 2013 (RECORD). Nevertheless, because of the specific characteristics of the German health care system as well as specific data protection requirements, the need for a specific German reporting standard for secondary data analyses became evident. Therefore, STROSA was revised and tested by a task force of 15 experts from the working group Collection and Use of Secondary Data (AGENS) of the German Society for Social Medicine and Prevention (DGSMP) and the German Society for Epidemiology (DGEpi) as well as from the working group Validation and Linkage of Secondary Data of the German Network for Health Services Research (DNVF). The consensus STROSA-2 checklist includes 27 criteria, which should be met in the reporting of secondary data analysis from Germany. The criteria have been illustrated and clarified with specific explanations and examples of good practice. The STROSA reporting standard aims at stimulating a wider scientific discussion on the practicability and completeness of the checklist. After further discussions and possibly resulting modifications, STROSA shall be implemented as a reporting standard for secondary data analyses from Germany. This will guarantee standardized and complete information on secondary data analyses enabling assessment of their internal and external validity.

A conventional hot rolled, low alloy carburizing steel (C: 0.21 wt.-%; Cr: 1.08 wt.%; Mn: 1.36 wt.%) has been investigated in terms of inhomogeneous phase transformations and anisotropic size changes during heating to austenitizing temperature and during slow cooling from austenitizing temperature to room temperature. A detailed study was executed on dilatometer specimens. The results were compared with the size changes of shafts with similar heat treatment. Ferrite nucleated first at selected chain-like positions and a pronounced ferrite/pearlite rodlike structure was formed. After reaustenitizing the rodlike structure appeared exactly at the same position. At intermediate transformation stages broad regions were still untransformed while other regions had an advanced transformation state. Dilatometer specimens with different orientations to the former rolling direction of the bar had different changes in length, which indicates an anisotropic size change. Cylindrical shafts showed a similar macroscopic size change like the small dilatometer specimens. For the dilatometer specimens as well as for the shafts the absolute valuese of the size change depended on the initial microstructure.

In order to improve the rolling contact fatigue (RCF) behavior of gear steels, a concept to increase their damage tolerance is developed alternatively to the conventional approach of improving the degree of steel cleanliness. For that purpose, Cu is used as a main alloying element in order to trigger the precipitation of nano‐sized Cu precipitates which shall improve the strain‐hardening rate of the martensitic matrix of Cu‐alloyed 18CrNiMo7‐6 steel surrounding a non‐metallic inclusion during plastic deformation. In this way, early component failure may be avoided and the maintenance costs of, e.g., wind energy converters may be kept low. The experimental analysis shows that nano‐sized Cu precipitates influence the material's strength, ductility, and strain‐hardening behavior under tension, depending on their coherence. Among others, the latter is related to strain‐induced martensitic transformation of coherent Cu. The structure of the Cu precipitates is studied by TEM and SANS analysis. The Cu‐alloyed steel also shows an increased hardening‐exponentCHT studied by cyclic hardness test (CHT) PHYBALCHT. Fatigue tests of specimens with coherent precipitates show cyclic hardening until a critical stress amplitude. Above that, stress amplitude cyclic softening is detected. An increased damage tolerance could be obtained for a 1 mass‐% Cu‐alloyed 18CrNiMo7‐6 steel.

tizing were investigated experimentally for the low alloy SAE 5120 (DIN EN 20MnCr5) steel by using a thermomechanical simulator. Creep within the initial ferrite/pearlite microstructure and within austenite as well as transformation plasticity and anisotropic transformation strain due to a banded microstructure during the ferrite/pearlite → austenite transformation were found as significant effects. With these data a FEM-simulation model for heating and austenitizing was implemented. Exemplarily the plastic behavior during heating of cylindrical shafts was analyzed by FEM-simulation. Plastizität des niedriglegierten Stahls 20MnCr5 während des Erwärmens und AustenitisierensDie Plastizitätseffekte des niedrigle-Zusammenfassung: gierten Stahls 20MnCr5 während des Erwärmens und Austenitisierens wurde mit Hilfe eines thermomechanischen Simulators experimentell untersucht. Dabei wurde Kriechen sowohl im ferritisch/perlitischen Ausgangsgefüge als auch im Austenit festgestellt. Weiter sind die Umwandlungsplastizität und eine anisotrope Umwandlungsdehnung aufgrund eines zeiligen Ausgangsgefüges während der Ferrit/Perlit → Austenit-Umwandlung festgestellt worden. Die Daten wurden in ein FEM-Simulationsmodell integriert. Beispielhaft wurde das plastische Verhalten beim Erwärmen von zylindrischen Wellen simuliert.

Kurzfassung Das Maß- und Formänderungsverhalten von Bauteilen beim Abschrecken kann erstens in der Bauteilvorgeschichte und dem dabei aufgebauten Verzugspotenzial begründet sein. Dieser Anteil des Verzugspotenzials wird durch Asymmetrien und Inhomogenitäten in der Geometrie (Massenverteilung) und den Verteilungen der chemischen Zusammensetzung, des Gefüges und der Eigenspannungen gebildet. Zweitens kann aber auch der eigentliche Wärmebehandlungsprozess und speziell der Abschreckprozess Verzüge verursachen. So beinhaltet jede Abschreckung ein eigenes Verzugspotenzial, das sich im allgemeinen Fall über Asymmetrien und Inhomogenitäten im Wärmeübergang definiert. In der vorliegenden Arbeit wird über Versuche berichtet, in denen zum einen das Verzugspotenzial des Fertigungsprozesses gezielt beeinflusst und zum anderen das Verzugspotenzial des Abschreckprozesses durch die Verwendung von hochsymmetrischen Gasdüsenfeldern minimiert wurde. Durch diese Randbedingungen lässt sich eine klare Trennung der Verzugsursachen herbeiführen.