Investigations of microstructure of resistance spot-welded joints made of HSLA340 and DP600 steels

• Autorzy: Ignasiak A. , Korzeniowski M. , Ambroziak A.

Warianty tytułu

PL

Badanie mikrostruktury złączy zgrzewanych punktowo ze stali HSLA340 I DP600

• Języki publikacji: EN

Abstrakty

EN

The paper presents results of metallographic investigations of spot welds made of high-strength steel HSLA340 and dual-phase DP600 steel. Low-carbon martensite microstructure was found in the weld nugget of HSLA steel. The DP600 steel shows martensite and bainite microstructure. For both steels, no carbides of microadditives were found because they dissolved in liquid nugget and could not precipitate again because of rapid heat abstraction. Moreover, no transcrystallisation was found in both steels, which proves good mixing of the materials within the weld.

PL

W artykule opisano wyniki badań metalograficznych zgrzein punktowych wykonanych ze stali o podwyższonej wytrzymałości HSLA340 i dwufazowej stali DP600. Badania wykazały, ze jądro zgrzeiny dla stali HSLA ma mikrostrukture martenzytu niskowęglowego, a dla stali DP600 martenzytu i bainitu. Dla obu gatunków stali w zgrzeinie nie obserwowano węglików mikrododatków stopowych, gdyż w czasie tworzenia ciekłego jądra zostały one rozpuszczone, a w wyniku szybkiego odprowadzania ciepła do elektrod nie zdołały sie ponownie wydzielić. Ponadto dla obu gatunków stali zaobserwowano brak transkrystalizacji, co świadczy o dobrym wymieszaniu sie materiałów w obrebie zgrzeiny.

Słowa kluczowe

EN

resistance spot welding; high-strength steel; metallographic examination

• 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: 2012
• Tom: Vol. 57, iss. 4
• Strony: 1081--1086
• Opis fizyczny: Bibliogr. 12 poz., rys.

Twórcy

autor

Ignasiak A.

autor

Korzeniowski M.

autor

Ambroziak A.

• Student of Mechanical Faculty of Wroclaw University of Technology - The Rudolf Haimann Students' Scientific Circle

Bibliografia

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