The influence of the hardening conditions on the mechanical properties of ductile cast iron

• Autorzy: Giętka T. , Dymski S.
• Języki publikacji: EN

Abstrakty

EN

Ductile cast iron has been austempered according to two variants. The first treatment variant was austenitizing at a temperature t_γ = 830, 860 and 900 °C and holding at a temperature t_pi = 400 and 300 °C for 8÷64 min. Second variant treatment was two-phase austenitizing. Firstly, it was heated at a temperature t_γ = 950 °C and after forecooling and chilling at a temperature t_γ' = 900, 860 and 830 °C isothermal process was conducted in the same conditions as in the first variant. The cast iron with ferritic matrix was austempered. After hardening the mechanical (R_{p0,2, Rm}) and plastic (A₅) properties were examined as well as the microstructure of matrix and hardness. It was noticed that the heat treatment carried out according to variants I and II lead to attaining cast iron of grade: ADI EN-GJS-800-8, EN-GJS-1200-2, EN-GJS-1400-1 according to PN–EN 1564 : 2000; in addition, ductility of these grades was 1,5÷4 times bigger than the minimum standard material requirements.

Słowa kluczowe

EN

austenitizing temperature; isothermal process; mechanical properties; ductile cast iron

PL

temperatura austenityzowania; proces izotermiczny; właściwości mechaniczne; żeliwo sferoidalne

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2010
• Tom: Vol. 10, iss. 1 spec.
• Strony: 63--68
• Opis fizyczny: Bibliogr. 17 poz., rys., tab., wykr.

Twórcy

autor

Giętka T.

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

autor

Dymski S.

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

Bibliografia

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