Microstructural aspects of long-term ageing of martensitic 9% Cr steel with and without boron addition

• Autorzy: Golański Grzegorz , Merda Agata , Klimaszewska Klaudia

Identyfikatory

DOI

10.32730/imz.2657-747.19.1.4

Warianty tytułu

PL

Mikrostrukturalne aspekty długotrwałego starzenia stali martenzytycznych typu 9% Cr z dodatkiem i bez dodatku boru

• Języki publikacji: EN

Abstrakty

EN

The study covered 9% Cr martensitic steels - X10CrMoVNb9-1 (P91) and X13CrMoCoVNbNB9-2-1 (PB2) after long-term ageing at the temperature of 620°C and soaking time up to 50,000 hours. The microstructural investigations of the tested steels were carried out using a TITAN 80-300 transmission electron microscope. The analysis of the changes in the microstructure included the identification of precipitates and computer image analysis: the measurement of dislocation density and mean diameter of the precipitates. The tests showed that the analysed steels still retained the lath martensitic microstructure, but also the processes of matrix softening were observed. The microstructure of the examined steels also showed numerous precipitates with various morphologies. The micro-addition of boron in the PB2 steel, compared with the P91 steel, influenced the retardation of the microstructure degradation processes through the limitation of the growth of M23C6 precipitates and Laves phase. This resulted in a slowdown in the processes of recovery and polygonisation of the matrix of the tested steel.

PL

Badaniu poddano martenzytyczne stale typu 9% Cr - X10CrMoVNb9-1 (P91) oraz X13CrMoCoVNbNB9-2-1 (PB2) po długotrwałym starzeniu w temperaturze 620°C i czasie wygrzewania do 50 000 godzin. Badania mikrostrukturalne badanych stali przeprowadzono za pomocą transmisyjnego mikroskopu elektronowego TITAN 80–300. Analiza zmian w mikrostrukturze obejmowała identyfikację wydzieleń oraz komputerową analizę obrazu: pomiar gęstości dyslokacji i średniej średnicy wydzieleń. Przeprowadzone badania wykazały, że analizowane stale posiadały nadal zachowaną listwową mikrostrukturę martenzytyczną, ale także obserwowano procesy mięknięcia osnowy. W mikrostrukturze badanych stali widoczne były również liczne wydzielenia o różnej morfologii. Mikrododatek boru w stali PB2 w porównaniu do stali P91 wpłynął na spowolnienie procesów degradacji mikrostruktury poprzez ograniczenie wzrostu wydzieleń M23C6 i fazy Lavesa. Wpłynęło to na spowolnienie procesów zdrowienia i poligonizacji osnowy badanej stali.

Słowa kluczowe

EN

martensitic steel; PB2 steel; P91 steel; degradation of microstructure

PL

stal martenzytyczna; stal PB2; stal P91; degradacja mikrostruktury

• Wydawca: Sieć Badawcza Łukaszewicz - Instytut Metalurgii Żelaza im. Stanisława Staszica
• Czasopismo: Journal of Metallic Materials
• Rocznik: 2019
• Tom: Vol. 71, no. 1
• Strony: 27--33
• Opis fizyczny: Bibliogr. 18 poz., rys., tab.

Twórcy

autor

Golański Grzegorz

• Czestochowa University of Technology, Faculty of Production Engineering and Materials Technology Institute of Materials Engineering

autor

Merda Agata

• Czestochowa University of Technology, Faculty of Production Engineering and Materials Technology Institute of Materials Engineering

autor

Klimaszewska Klaudia

• Czestochowa University of Technology, Faculty of Production Engineering and Materials Technology Institute of Materials Engineering

Bibliografia

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Uwagi

Opracowanie rekordu ze środków MNiSW, umowa Nr 461252 w ramach programu "Społeczna odpowiedzialność nauki" - moduł: Popularyzacja nauki i promocja sportu (2020).