Studium přechodových oblastí heterogenních svarových spojů

Abstract

The production of electric energy and heat belongs to the important branch of industry production in Czech Republic and worldwide as well. As important sources we can still nowadays consider coal power plants even if there exist nuclear plants and further alternative sources. The main task during building of new energetic complexes and renewing existing ones is increasing of effectiveness of energetic devices, which is possible only through increasing of temperature and/or steam pressure. The expectations are that effectiveness of energetic devices will increase from today approximately 35% to 43%. Different temperatures of single plants components need use of different types of heat-resisting materials, which need to be welded. One of suggested connection types, used with new thermal power plants, is heterogeneous weld connection of steel P92 (X10CrWMoVNb9-2) with steel 1.4918 (X6CrNiMo17-13-2), this means weld connection of austenitic steel and martensitic steel. Research and verification of mentioned weld connection type becomes the main task of this dissertation. The experiment works concentrates on influence of welding and heat treatment process on weld joint properties forcefully to microstructure, chemical analyses and creep properties. The set of results of this dissertation is useful in practical applications during designing and approval of welding technology of heterogeneous weld joints of steel P92 (X10CrWMoVNb9-2) and steel 1.4918 (X6CrNiMo17-13-2).