Predicting ADI mechanical properties

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

Abstrakty

EN

Ductile cast iron was quench-hardened with the isothermal transformation according to two alternatives. The first treatment alternative consisted in the austenitizing process at temperature t\gamma = 830, 860 i 900 oC and annealing at temperature tpi = 400, 350 and 300oC in a period of time up to 240 min. The second treatment alternative consisted in dual-stage austenitizing. The material was annealed in temperature of t\gamma = 950oC and cooled to temperature t\gamma = 900, 860 and 830oC. The isothermal transformation was performed in the same conditions as in the first alternative. The cast iron was ferritizingly annealed before the isothermal quench-hardening. The cast iron matrix after the annealing was ferritic. Metallographic cubic specimens with the size about of 10 mm were quench-hardened with the isothermal transformation. Matrix microstructure, austenite percentage and Vicker's hardness were determined using the specimens. Hardness test results were used to determine, on the base of material coefficients, tensile strength Rm, yield strength Rp0,2 and deformation A5. Tests showed that heat treatment according to two alternatives of the quench hardening led to obtain ADI cast iron with accordance to PN-EN 1564 : 2000 grade: EN-GJS-800-8, EN-GJS-1000-5, EN-GJS-1200-2. Only ausferritic cast iron was assumed as a base of qualification.

Słowa kluczowe

EN

austenitizing; isothermal transformation; mechanical properties

PL

austenityzowanie; przemiana izotermiczna; właściwości mechaniczne

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2009
• Tom: Vol. 9, iss. 3
• Strony: 267--274
• Opis fizyczny: Bibliogr. 20 poz., rys., tab., wykr.

Twórcy

autor

Giętka T.

autor

Dymski S.

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

Bibliografia

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