The influence of carbonitriding process on microstructure and mechanical properties of micro-alloyed steel

The article deals with the analysis of carbonitrided samples of S460MC microalloyed thermo-mechanically treated steel. The steel surface was saturated with carbon and nitrogen at the temperature of 860 °C. The nitrogen-methanole atmosphere with Amonnia addition was used for surface saturation in the process of carbonitriding. Oil hardening and tempering at 200 °C/1 hour followed after the diffusion saturation of experimental steel sample. The surface layer was composed of martensite, retained austenite and fine carbides of alloying elements. This was demonstrated with light microscopy and confirmed by TEM (transmission electron microscope). The paper also presents the results of chemical composition and hardness measurement

Segregation and microstructure heterogenity of single crystal nickel based superalloy ŽS 26

Microstructural heterogenity was examined in the as-cast microstructure of directionally solidified ZS 26 nickel based superalloy. The distribution of elements in primary and secondary dendrite growth direction was determined by quantitative EDX analysis. Measurements of elemental partitioning show apparent segregation behaviour of Al, Ti, W, and Ni during solidification. The series of one stage solution were used to homogenize samples microstructure of samples and simultaneously to study the solutes redistribution

Medium range flood forecasting example EFAS

Europe repeatedly observes flood events that affect several countries at the same time and which require the coordination of assistance at the European level. The European Flood Awareness System (EFAS) has been developed specifically to respond to the need for forecasting transnational floods with sufficient lead time to allow coordination of aid at the European level in case the national capacities for emergency management are exceeded. In order to achieve robust and reliable flood forecasting at the continental scale with lead times up to 10 days, EFAS promotes probabilistic forecasting techniques based on multiple numerical weather prediction inputs including ensemble prediction systems. Its aim is to complement existing national flood forecasting services with added value information and to provide European decision makers with coherent overviews on ongoing and upcoming floods in Europe for better planning and coordination of aid. To date, EFAS is a unique system providing daily, probabilistic flood forecast information for the entire of Europe on a single platform. Being a complementary system to national ones, EFAS predicts the probabilities for exceeding critical flood thresholds rather than quantitative information on stream flows. By maintaining a dedicated, multinational partner network of EFAS users, novel research could be transferred directly to the operational flood forecasting centers in Europe. EFAS development started in 2003, and the system has become fully operational under the umbrella of Emergency Management Service of the European Copernicus Space Program in 2011

Forecasters priorities for improving probabilistic flood forecasts.

Hydrological ensemble prediction systems (HEPS) have in recent years been increasingly used for the operational forecasting of floods by European hydrometeorological agencies. The most obvious advantage of HEPS is that more of the uncertainty in the modelling system can be assessed. In addition, ensemble prediction systems generally have better skill than deterministic systems both in the terms of the mean forecast performance and the potential forecasting of extreme events. Research efforts have so far mostly been devoted to the improvement of the physical and technical aspects of the model systems, such as increased resolution in time and space and better description of physical processes. Developments like these are certainly needed; however, in this paper we argue that there are other areas of HEPS that need urgent attention. This was also the result from a group exercise and a survey conducted to operational forecasters within the European Flood Awareness System (EFAS) to identify the top priorities of improvement regarding their own system. They turned out to span a range of areas, the most popular being to include verification of an assessment of past forecast performance, a multi-model approach for hydrological modelling, to increase the forecast skill on the medium range (>3 days) and more focus on education and training on the interpretation of forecasts. In light of limited resources, we suggest a simple model to classify the identified priorities in terms of their cost and complexity to decide in which order to tackle them. This model is then used to create an action plan of short-, medium- and long-term research priorities with the ultimate goal of an optimal improvement of EFAS in particular and to spur the development of operational HEPS in general