Influence of cementite precipitation on the extent of bainite reaction in FE-CR-SI-C steel

• Autorzy: Ławrynowicz Z.
• Języki publikacji: EN

Abstrakty

EN

The paper presents an investigation of the extend of bainite reaction in the case of cementite precipitation. Experimental measurements of volume fraction of bainitic ferrite and volume of the untransformed austenite indicate that there is a necessity of carbides precipitation from austenite. 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. The comparison of experimental data with the T0, T0' and A3' phase boundaries suggests the likely mechanism of bainite reaction in Fe-Cr-Si-C steel is displacive rather than diffusional. A consequence of the precipitation of cementite from austenite during austempering is that the growth of bainitic ferrite can continue to larger extent and that the resulting microstructure is not an ausferrite but it is a mixture of bainitic ferrite, retained austenite and carbides.

Słowa kluczowe

EN

bainite transformation; carbide precipitation; carbon diffusion

• Wydawca: Faculty of Ocean Engineering and Ship Technology, Gdańsk University of Technology
• Czasopismo: Journal of Polish CIMAC
• Rocznik: 2011
• Tom: Vol. 6, no 3
• Strony: 137--144
• Opis fizyczny: Bibliogr. 15 poz., rys., tab.

Twórcy

autor

Ławrynowicz Z.

• University of Technology and Life Sciences in Bydgoszcz, Mechanical Engineering Faculty Department of Materials Science and Engineering, av. Kaliskiego 7, 85-789 Bydgoszcz, Poland,

Bibliografia

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