The assessment of hot cracking susceptibility of ferritic-austenitic cast iron

• Autorzy: Stradomski Z. , Soiński M. S. , Stradomski G.
• Języki publikacji: EN

Abstrakty

EN

An inspiration to the research work has arisen from the problems related to cracking of massive castings made of ferritic-austenitic cast steel. The shape and the character of crack trajectories indicate that they are hot cracks. Investigations have included two cast steel grades, namely GX2CrNiMoN25-6-3 and GX2CrNiMoCuN25-6-3-3, because some customers had demanded for copper addition which makes possible the ageing treatment; also the alloys with increased carbon content have been investigated and this resulted from difficulties in obtaining sufficiently low carbon content (C_max 0,03%) in many Polish foundries which are not equipped with argon-oxygen devices for cast steel decarburizing. The method of critical size of a specimen similar in shape to the Hall test specimen has been applied to examine the cast steel susceptibility to hot cracking. The examination results undoubtedly indicate the negative influence of the increased carbon content, especially in the presence of copper. The intercrystalline character of cracks which propagate along the dendritic austenite precipitates suggests that the peritectic reaction occurs in the final stage of solidification, being induced by segregation of the strong austenite-forming alloying elements. The increased hot cracking susceptibility of the ferrite-austenite cast steel containing copper, particularly with simultaneously increased carbon content, indicates that the implementation of production technologies concerning this material should be started with production of castings made of alloy grades without copper addition.

Słowa kluczowe

EN

innovative foundry materials; innovative foundry technologies; duplex cast steel; hot cracking; solidification; segregation

PL

odlewnictwo nowoczesne; materiały odlewnicze; nowoczesne technologie odlewnicze; staliwo typu duplex; pękanie; krzepnięcie

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2010
• Tom: Vol. 10, iss. 2
• Strony: 159--162
• Opis fizyczny: Bibliogr. 14 poz., fot., tab.

Twórcy

autor

Stradomski Z.

• Technical University of Częstochowa, Department of Materials Science, Poland

autor

Soiński M. S.

• Chair of Foundry, Technical University of Częstochowa, Poland

autor

Stradomski G.

• Technical University of Częstochowa, Institute of Modelling and Automation of Plastic Working Processes, Poland

Bibliografia

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