Continuous heating from as-quenched state in a new hot-work 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 a new hot-work steel. Moreover, the differences in hardness and microstructure of samples of the investigated steel in relationship to the heat treatment were evaluated. 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. In the case of investigations of the microstructural changes, quenched samples were heated with a heating rate of 0.05°C/s to the temperatures of 150, 280 and 650°C. The microstructure of investigated steel were examined using light microscope Axiovert 200 MAT, scanning electron microscope Stereoscan 120 and transmission JEM200CX microscope. The measurements of hardness were performed with the Vickers HPO250 apparatus. 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, nucleating independently. TEM investigations, focused on the determination of a degree of phase transformations during continuous tempering, showed compatibility of the microstructure with the CHT diagram for tested steel. Research limitations/implications: Description of the kinetics of phase transformations during tempering of a new hot working steel. Practical implications: This results may be used to design new technologies of tempering of this steel and new designed hot-work steels. Originality/value: Characterization of kinetics phase transformations during continuous heating from asquenched state in new hot-work steel. Moreover it was shown, that the heating rate from asquenched state has a strong influence on a hardness after tempering.

Słowa kluczowe

EN

tool materials; hot work steel; tempering; CHT diagram

PL

materiały narzędziowe; stal narzędziowa do pracy na gorąco; odpuszczanie

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2007
• Tom: Vol. 28, nr 9
• Strony: 517--524
• Opis fizyczny: Bibliogr. 17 poz., il., wykr.

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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