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Unlike medium‐carbon and high‐carbon steels, the effect of the high‐temperature deformation process on the bainite transformation of low‐carbon steels is yet to be fully understood. Processes with varying high‐deformation temperatures and reductions are designed to investigate the bainitic transformation of low‐carbon steel. The results indicate that compared with the undeformed samples, for all deformation temperatures (850, 950, and 1050 °C) in the austenite temperature range, a small reduction of 5% accelerates the bainite transformation rate corresponding to the samples, and this can be attributed to the increase in the driving force. The promoting effect is increased with a decrease in deformation temperature. However, a relatively large reduction of the samples by 25% and 50% decreases the bainite transformation rate, and the inhibiting effect increases with decreasing deformation temperature. In addition, the amount of bainite increases at 1050 °C under all strains, and the amount is higher than the amount observed in undeformed samples. For the deformation temperature of 850 °C, the bainite amount increases under conditions of small reduction (5%), whereas the bainite amount decreases under large strain conditions (50% at 850 and 950 °C). The results provide a theoretical basis for optimizing the processing parameters associated with the production of low‐carbon bainite steels. [ABSTRACT FROM AUTHOR]

Metamorphic transformation rates are classically determined on decimetre‐scale field samples and from laboratory experiments at smaller scales. Here we present a geophysical approach based on field data and joint geophysical–petrological modelling to quantify the average rate of metamorphic transformations at the 10–100‐kilometre and million‐year scales. The model simulates the eclogitization of Indian lower crust as it penetrates beneath southern Tibet. Metamorphic transformation of the lower crust is tracked by its densification, the effect of which is then compared to observed gravity anomalies. From the modelling we find that the Indian lower crust's overall densification requires a partially hydrated initial composition. Moreover, the modelled evolution of this densification compared to what is predicted by pressure–temperature–density grids is consistent with delayed, far‐from‐equilibrium metamorphism. The Indian lower crust descends underneath the Himalaya until beneath southern Tibet in a thermodynamically metastable state until the first dehydration reactions are reached. This observation is used to determine the average rate of metastable rock transformation to an eclogite facies assemblage, constrained at between ~6 × 10−9 and 5 × 10−7 g/cm2/year, and reaction affinity at 0.8–1.6 kJ/mol oxygen. Compared to field and laboratory data, this range of results matches the effective rates typically associated with regional metamorphism. This fit and correlation across the scales legitimates the use of transformation rates determined at small scales in large‐scale geodynamic studies. [ABSTRACT FROM AUTHOR]

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Abstract: Modeling martensitic phase transformation in SMAs has become a key to understand the transformation behavior in terms of their temperature and stress response. In the present work a new method based on a statistical physics concept has been developed for the description of transformation kinetics, total strain and their rates in polycrystalline solids undergoing displacive temperature induced phase transformations. As a result the model explains the kinetics and strain evolution for a polycrystal without the requirement of assumptions on internal variables and their constraints. Instead it is based on fundamental properties of the SMA single crystal, only. [Copyright &y& Elsevier]

Abstract: Landscape change is driven by various actors and forces which trigger a specific rate of change. Today, many landscapes change in a direction and with a rate considered unsustainable. Historical insights on actors, driving forces and resulting changes can provide a valuable basis to efficiently control or direct changes. In this paper actors and driving forces of landscape change of the last 120 years are studied in five areas on the northern fringe of the Swiss Alps. Rates of landscape change were reconstructed based on maps. Expert interviews with farmers, politicians, planners and historians as well as historical documents helped in identifying actors and driving forces of the detected landscape change. The contributions of actors and driving forces to landscape change were analyzed by type of driving force (political, economic, cultural, technological and natural/structural). The analysis revealed some key forces, like technological innovations and attitudes and beliefs, operating on several institutional levels and influencing landscape change on a broad basis. Comparing the municipalities disclosed no significant differences regarding the relative contributions of different actors. However, a comparison of the time period before and after World War II revealed distinctive differences in relevant actors and driving forces. Thus, decision-making, policy, and planning must be aware of changing actors and driving forces over time. [Copyright &y& Elsevier]