The kinetics of phase transformations during the tempering of HS6-5-2 high-speed steel

• Autorzy: Bała P. , Pacyna J. , Krawczyk J.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The reasons for write this paper was described the kinetics of phase transformations during tempering of hardened HS6-5-2 high-speed steel. Moreover, the influence of the heating rate on the retained austenite transformation. Design/methodology/approach: CHT diagram was with dilatometric method determined. The influence of the heating rate on the retained austenite transformation as well as the results of threefold tempering at 560°C were also determined. Findings: During heating of the samples of the quenched HS6-5-2 steel the occurrence of 4 principal transformations was determined. These are: precipitation of ε carbide, M3C precipitation, transformation of retained austenite and precipitation of alloy carbides of MC and M2C type. It was shown that in the quenched high-speed steels a part of retained austenite is already transformed during heating for tempering, but its significant part is transformed only during cooling after tempering as well as during consecutive heatings for temperings. Research limitations/implications: The new CHT diagram of investigated steel was determined. Practical implications: The obtained CHT diagram may be used to design new technologies of tempering of this steel. Originality/value: The new CHT diagram.

Słowa kluczowe

EN

tool materials; tempering; CHT diagram; retained austenite

PL

materiały narzędziowe; odpuszczanie; wykres CTPc; austenit szczątkowy

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2006
• Tom: Vol. 18, nr 1-2
• Strony: 47--50
• Opis fizyczny: Bibliogr. 19 poz., rys., tab., wykr.

Twórcy

autor

Bała P.

• Faculty of Metals Engineering and Industry Computer Science, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Krakow, Poland

autor

Pacyna J.

• Faculty of Metals Engineering and Industry Computer Science, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Krakow, Poland

autor

Krawczyk J.

• Faculty of Metals Engineering and Industry Computer Science, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Krakow, Poland

Bibliografia

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