The influence of saturation of cast iron austenite with carbon on the ausferrite transformation

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

Abstrakty

EN

Austenitizing during quench hardening of the ductile cast iron influences the content of carbon in austenite depending on the soaking heat. On the other hand, the saturation of austenite impacts its transformation in the ausferritizing process of a metal matrix and forming of microstructure. Ductile cast iron with the ferrite matrix was hardened with isothermal transformation in the range of ausferritizing in temperature [...]. Microstructure was investigated, there were also defined the proportion of austenite in the matrix of the cast iron and the content of carbon in it and hardness and impact strength in unnotched specimens. It was stated, that the precooling temperature deciding on the content of carbon in austenite influences kinetics of the ausferritic transformation, the content of carbon in the [gamma] phase and impact strength and, in a less degree, hardness. As a result of gradual austenitizing the cast iron after quench hardening, in some conditions of treatment, reached mechanical properties corresponding, according to the ASTM A 897 standard, with high grades of ADI. Chilling in the range of austenitizing in temperature 850 and 800 oC led to the decrease of carbon in austenite what influenced positively on the matrix microstructure and properties of the ADI. Investigations in this range will be continued.

Słowa kluczowe

EN

ductile cast iron; austenitizing; austempered; austenite; hardness; impact strength

PL

żeliwo sferoidalne; austenit; carbon; pierwiastki stabilizujące; twardość; odporność na uderzenia

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2007
• Tom: Vol. 7, iss. 3
• Strony: 241--246
• Opis fizyczny: Bibliogr. 16 poz., rys., tab.

Twórcy

autor

Giętka T.

autor

Szykowny T.

autor

Dymski S.

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

Bibliografia

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