Reason analysis of welded joints cracking joints in membrane wall elements as a basis for selection of the chemical composition of new generation low-alloy bainitic steel on evaporator collectors for boilers with supercritical working parameters

• Autorzy: Dobrzański J.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The aim of the paper was to assess the impact of the chemical composition and the cooling rate on the type of microstructure, the level of mechanical properties and crack sensitivity of welded joints of membrane walls of the evaporator collector for boilers made of new generation low-alloy bainitic steels for power engineering for the application in boilers with supercritical parameters. Design/methodology/approach: Through SEM observation using the EBSD technique occurring types of microstructures, depending on the chemical composition and cooling speed of tubes and flat bars made of 7CrMoVTiB10 - 10 steels assigned for membrane walls of the evaporator collectors for boilers have been revealed. For each types of microstructure mechanical properties have been determined. The achieved results have been referred to the designated weldability factors; chemical carbon equivalent Ce and the fracture sensitivity parameter associated with the phase transitions of Pcm . Findings: The influence of the chemical composition and the cooling rate on the formed microstructure and the corresponding level of mechanical properties and the value of carbon equivalent value Ce and the fracture sensitivity parameter due to 7CrMoVTiB10-10 steel welding. Originality/value: Applied methodology and a proposed modification of the chemical composition will be used by manufacturers in modifying and developing new technology of manufacturing membrane walls of the evaporator collectors for boilers made of new generation low-alloy bainitic steels for power engineering.

Słowa kluczowe

EN

CrWVNb9-6 (P23) steel; 7CrMoVTiB10-10 (P24) steel; microstructure; mechanical properties

PL

stal CrWVNb9-6 (P23); stal 7CrMoVTiB10-10 (P24); mikrostruktury; właściwości mechaniczne

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2013
• Tom: Vol. 64, nr 2
• Strony: 228--236
• Opis fizyczny: Bibliogr. 34 poz.

Twórcy

autor

Dobrzański J.

• Institute for Ferrous Metallurgy, ul. K. Miarki 12, 44-100 Gliwice, Poland

Bibliografia

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