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

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

Abstrakty

EN

Purpose: This work contains a detailed description of the kinetics of phase transformations during tempering of hardened HS6-5-2 high-speed steel. Moreover, the microstructure development in tested samples, reflecting the extend of the phase transformations during tempering, was discussed too. Design/methodology/approach: CHT diagram, illustrating the kinetics of phase transformations during continuous heating (tempering) from as-quenched state of investigated steel, was elaborated using a DT 1000 dilatometer of a French company Adamel. 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: Heating of the investigated steel from the as-quenched state resulted in the occurrence of 4 primary transformations: 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. Examination of the microstructure of investigated steel, mainly focused on microstructural development relating to the advancement of transformations during continuous tempering, showed an adequacy of the microstructural changes to CHT diagrams. 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. Keywords: Tool materials; Tempering; CHT - diagram; Retained austenite

Słowa kluczowe

EN

tool materials; tempering; CHT diagram; retained austenite

PL

materiały narzędziowe; odpuszczanie; wykres CTPc; austenit szczątkowy

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2009
• Tom: Vol. 35, nr 2
• Strony: 69--76
• Opis fizyczny: Bibliogr. 21 poz.

Twórcy

autor

Bała P.

autor

Pacyna J.

autor

Krawczyk J.

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

Bibliografia

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