Ti/Al multi-layered sheets: Accumulative roll bonding (Part A)

Co-deformation of Al and Ti by accumulative roll bonding (ARB) with intermediate heat treatments is utilized to prepare multi-layered Ti/Al sheets. These sheets show a high specific strength due to the activation of various hardening mechanisms imposed during deformation, such as: hardening by grain refinement, work hardening and phase boundary hardening. The latter is even enhanced by the confinement of the layers during deformation. The evolution of the microstructure with a special focus on grain refinement and structural integrity is traced, and the correlation to the mechanical properties is shown

Cooperation, motivation and social balance

This paper examines the reflexive interplay between individual decisions and social forces to analyze the evolution of cooperation in the presence of “multi-directedness,” whereby people's preferences depend on their psychological motives. People have access to multiple, discrete motives. Different motives may be activated by different social settings. Inter-individual differences in dispositional types affect the responsiveness of people's motives to their social settings. The evolution of these dispositional types is driven by changes in the frequencies of social settings. In this context, economic policies can influence economic decisions not merely by modifying incentives operating through given preferences, but also by influencing people's motives (thereby changing their preferences) and by changing the distribution of dispositional types in the population (thereby changing their motivational responsiveness to social settings)

Entwicklung einer korrosions- und verschleißbeständigen Eisenbasisschicht

Gegenstand der dargestellten Arbeit war die Entwicklung eines neuen Beschichtungswerkstoffs für den Verschleiß- und Korrosionsschutz von Stahlkomponenten insbesondere für Anwendungen in der Ölbohrtechnik. Die Arbeit konzentrierte sich hierbei auf eine kostengünstige Beschichtungslösung für großvolumige Komponenten, mit dem Ziel, in Zukunft die bislang hierfür verwendeten, teuren hochlegierten Stahlgüten beispielsweise für Borgestänge oder Futterrohre gegen kostengünstige Stahlwerkstoffe ersetzen zu können. Für diesen Zweck wurde eine pulverförmige Eisenbasislegierung aus dem System Fe-Cr-Al-B-Si entwickelt, die für thermische Beschichtungsprozesse wie das thermische Spritzen oder das Auftraglöten geeignet ist. Es wurden hiermit Beschichtungsversuche mittels atmosphärischen Plasmaspritzens (APS) und Hochgeschwindigkeitsflammspritzens (HVOF) durchgeführt und die aufgespritzten Schichten zur Verbesserung der Haftfestigkeit in einem Ofenprozess umgeschmolzen und gesintert. Die metallurgischen Schichteigenschaften wurden metallographisch und rasterelektronenmikroskopisch analysiert. Zudem wurden ortsaufgelöste Härtemessungen und elektrochemische Korrosionsmessungen an den Schichten durchgeführt, die erfolgversprechende Erkenntnisse über die zu erwartende Verschleiß- und Korrosionsbeständigkeit des Schichtsystems lieferten

The Role of Income Aspirations in Individual Happiness

Does individual well-being depend on the absolute level of income and consumption or is it relative to one's aspirations? In a direct empirical test, it is found that higher income aspirations reduce people's utility, ceteris paribus. Individual data on reported satisfaction with life are used as a proxy measure for utility, and income evaluation measures are applied as proxies for people's aspiration levels. Consistent with processes of adaptation and social comparison, income aspirations increase with people's income as well as with the average income in the community they live in

Ti/Al Multi-Layered Sheets: Accumulative Roll Bonding (Part A)

Co-deformation of Al and Ti by accumulative roll bonding (ARB) with intermediate heat treatments is utilized to prepare multi-layered Ti/Al sheets. These sheets show a high specific strength due to the activation of various hardening mechanisms imposed during deformation, such as: hardening by grain refinement, work hardening and phase boundary hardening. The latter is even enhanced by the confinement of the layers during deformation. The evolution of the microstructure with a special focus on grain refinement and structural integrity is traced, and the correlation to the mechanical properties is shown