Mechanical Properties of VM12 Steel after 30 000 Hrs of Ageing at 600°C Temperature

• Autorzy: Golański G. , Zieliński A. , Słania J. , Jasak J.

Identyfikatory

DOI

10.2478/amm-2014-0230

Warianty tytułu

PL

Właściwości mechaniczne stali VM12 po 30 000 godzin starzenia w temperaturze 600°C

• Języki publikacji: EN

Abstrakty

EN

The paper describes the influence of different times of ageing on mechanical properties and microstructure stability in hardened and tempered VM12 steel exposed to service temperature - 600°C. Detailed microstructural and microchemical analysis of secondary phases was carried out using scanning electron microscopy (SEM + EDX) and X-ray phase analysis of carbide isolates. Performed research has proved high stability of strength properties of the investigated steel, which is connected with the lath stability of the microstructure of tempered martensite. Slight changes in strength properties were accompanied by over 50% reduction in impact strength KV of the examined cast steel, from the level of 83 J in the as-received condition to 38 J after 30 000 hrs of ageing at the temperature of 600°C. Significant decrease in impact energy KV of VM12 steel results from the growth of the amount and size of precipitations on grain boundaries.

PL

W pracy przedstawiono wyniki badań zmian w mikrostrukturze i właściwościach mechanicznych stali VM12 po 30000 godzin starzenia w temperaturze 600°C. Przeprowadzone badania wykazały, że długotrwałe starzenie stali VM12 prowadzi do względnego wzrostu wydzieleń po granicach ziaren, głównie po granicach ziaren byłego austenitu oraz skutkuje zanikiem wydzieleń typu MX oraz wydzielaniem fazy Lavesa. Zmiany w mikrostrukturze w niewielkim stopniu wpłyneły na zmiany właściwości wytrzymałościowych (granicy plastyczności, wytrzymałości na rozciąganie) o ok. 7%, natomiast spowodowały ponad 50% redukcje udarności KV z poziomu 83 J w stanie wyjściowym do 38 J po 30 000 godzin starzenia. Ponadto starzenie stali VM12 skutkowało ok. 16% obniżeniem twardości HV10 co powiązano z zanikiem wydzieleń typu MX.

Słowa kluczowe

EN

VM12 steel; ageing; microstructure; mechanical properties

PL

stal VM12; starzenie; mikrostruktura; właściwości mechaniczne

• Wydawca: Institute of Metallurgy and Materials Science of Polish Academy of Sciences ; Committee of Materials Engineering and Metallurgy of Polish Academy of Sciences
• Czasopismo: Archives of Metallurgy and Materials
• Rocznik: 2014
• Tom: Vol. 59, iss. 4
• Strony: 1351--1354
• Opis fizyczny: Bibliogr. 22 poz., rys., tab.

Twórcy

autor

Golański G.

• Institute of Materials Engineering, Czestochowa University of Technology, 19 Armii Krajowej Av., 42-200 Częstochowa, Poland

autor

Zieliński A.

• Institute for Ferrous Metallurgy, Miarki 12-14, 44-100 Gliwice, Poland

autor

Słania J.

• Department of Welding Technology, Institute of Mechanical Technologies, Czestochowa University of Technology, 21 Armii Krajowej Av., 42-200 Czestochowa, Poland

autor

Jasak J.

• Institute of Materials Engineering, Czestochowa University of Technology, 19 Armii Krajowej Av., 42-200 Częstochowa, Poland

Bibliografia

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