Analysis of carbon partitioning during ausferritic reaction in ADI

• Autorzy: Ławrynowicz, Z. , Dymski, S.
• Języki publikacji: EN

Abstrakty

EN

The investigation was carried out to examine the influence of temperature and times of austempering process on the maximum extend to which the ausferritic reaction can proceed and the carbon content in retained austenite. Specimens prepared from ductile cast iron were austenitised at 950°C for 60 minutes and austempered at four temperatures: 250, 300, 350 and 400°C. The samples were austempered at these temperatures for 15, 30, 60, 120 and 240 minutes and finally quenched to ambient temperature. Volume fractions of retained austenite and carbon concentration in the residual austenite have been observed by using X-ray diffraction. Additionally, carbon concentration in the residual austenite was calculated using volume fraction data of austenite and a model developed by Bhadeshia based on the McLellan and Dunn quasi-chemical thermodynamic model. It was found that the obtained extend of ausferritic transformation is only possible when the microstructure consists of not only ausferrite but additionally precipitated carbides.

Słowa kluczowe

PL

austenit szczątkowy; hartowanie izotermiczne; żeliwo sferoidalne

EN

retained austenite; ausferrite; austempring; ductile iron

• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2008
• Tom: Vol. 8, iss. 3
• Strony: 69-74
• Opis fizyczny: Bibliogr. 18 poz., rys., tab., wykr.

Twórcy

autor

Ławrynowicz, Z.

autor

Dymski, S.

• Department of Materials Science and Engineering, Mechanical Engineering Faculty, University of Technology and Life Sciences, 85-796 Bydgoszcz, av. Kaliskiego 7, Poland,

Bibliografia

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