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Bauteile im industriellen Ofen- und Apparatebau sind Temperaturen bis uber 1200 °C sowie mechanischer Beanspruchung und korrosivem Angriff durch die Umgebungsatmosphare ausgesetzt. Um die Eigenschaften der Nickelbasislegierung Alloy 602 CA unter diesen Bedingungen zu beschreiben, wurde das langzeitige Kriechverhalten bei Temperaturen von 800 bis 1200 °C in Kriechversuchen untersucht. Versuche mit Blecherzeugnissen unterschiedlicher Korngrose zeigen eine deutliche Erhohung der Kriechfestigkeit mit zunehmender Korngrose. Bei niedrigen Spannungen wurde eine ungewohnliche Abnahme der Dehnrate im tertiaren Kriechbereich beobachtet. Metallographische Untersuchungen liesen zwei verschiedene Mechanismen erkennen. Bei einem Teil der Proben ist eine Kornvergroberung als Ursache der Dehnratenabnahme anzunehmen. Im anderen Fall wird ein Zusammenhang mit der Oxidation der Kriechrisse im Probeninneren vermutet. Anhand der Versuchsergebnisse wurde eine Modellierung der minimalen Kriechgeschwindigkeit mit Berucksichtigung der Abhangigkeit von Korngrose, Spannung und Temperatur erstellt. Des Weiteren wurde ein korngrosenabhangiger Zeit-Temperatur-Parameter entwickelt, sowie ein Modell zur Berechnung des Kriechkurvenverlaufs. Trotz der Vielzahl der berucksichtigten Einflussgrosen wird bei der Nachrechnung von Versuchsergebnissen eine gute Genauigkeit der Modelle erreicht. Components used in industrial furnace and apparatus engineering are exposed to temperatures up to 1200 °C to mechanical, mostly static loading and to corrosive action caused by the ambient atmosphere. To characterize the properties of the nickel base alloy 602 CA under these conditions, the long-term creep behavior at temperatures from 800 to 1200 °C has been investigated in creep experiments. Tests on sheet metal material with different grain sizes show a considerable increase of creep strength with increasing grain size. At low stresses an abnormal reduction of the creep rate in the tertiary creep stage has been observed. Metallographic investigations have revealed two different mechanisms at work in these cases. In some, the strain rate reduction was attributed to grain coarsening. In others, a correlation with the oxidation of creep cracks is assumed. On the basis of the experimental results, a modeling of the minimum creep rate taking into account grain size, stress and temperature dependency, has been generated. Furthermore, a grain size dependent time-temperature parameter as well as a model for the calculation of creep curves has been developed. Despite the large number of influencing variables considered, a high level of precision of the models in the verification recalculation of experimental results has been achieved.

There is a current need for interventions that provide information to stroke survivors in a patient-centred, interactive, personalized and flexible manner. To this purpose, a standardized but content-flexible patient education programme based on the International Classification of Functioning, Disability and Health (ICF) was developed. This study evaluated the effect of this programme on perceived self-efficacy.Single-blind, randomized, multi-centre controlled trial.Stroke patients undergoing neurological rehabilitation were enrolled. Perceived self-efficacy was measured with the Liverpool Self-Efficacy Scale. Secondary outcomes were life satisfaction and self-perception of the impact of the stroke on life, measured with the WHOQOL and the Stroke Impact Scale, respectively. Data obtained at baseline, post-intervention and 6-month follow-up were analysed using multi-level models of change.Two hundred and thirteen patients received either the ICF-based patient education (n = 110) or an attention-placebo (n = 103) control intervention. Over time, patients' self-efficacy (p.01) and participation (p.01) improved, while emotional functioning (p.01) deteriorated, although no significant between-group differences were observed. Explorative analyses showed that gender, loci of control, difficulty in accessing health services after discharge and life satisfaction were significant predictors of self-efficacy.There was no significant benefit of the ICF-based patient education in comparison with an attention-placebo control group. Considering the importance of the programme for the further implementation of the ICF and the need of developing effective health education interventions for stroke, the methodology used was reviewed and an updated version proposed.

Objective To describe the development of an ICF-based patient education program, to present the results of its pilot test and to present the adaptations and final version of the program. Methods The education program was developed in five steps: (1) definition of relevant areas of functioning, (2) development of strategies to enhance self-efficacy in these areas, (3) development of material and instructions, (4) definition of modules and setting and (5) performance of a pilot test targeting acceptability and feasibility of the program. Results Eleven stroke patients were enrolled in the pilot test. The intervention was well accepted on the part of participants. The developed patient education program is structured in three modules. Module 1 targets to increase patients’ understanding of their current level of functioning. Module 2 targets to identify concrete problems and corresponding solutions regarding limited areas. Module 3 is a refresher session. Conclusion Feasibility and acceptability of the intervention were verified and a final version of the patient education program was developed. The effectiveness of the program will be evaluated in a randomized controlled trial. Practice implications Due to the universality of the ICF and availability of ICF tools, it is possible to adapt the intervention to different chronic conditions.