Microstructure evolution and phase composition of high-manganese austenitic steels

• Autorzy: Dobrzański L. , Grajcar A. , Borek W.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The aim of the paper is to determine the influence of hot-working conditions on microstructure evolution and phase composition of new-developed high-manganese austenitic steels. Design/methodology/approach: Determination of processes controlling strain hardening was carried out in continuous compression test using Gleeble 3800 thermo-mechanical simulator. Evaluation of processes controlling work hardening and occurring after deformation at 900°C were identified by microstructure observations of the specimens solution heat-treated after plastic deformation to a true strain equal 0.23, 0.50 and 0.91. Phase composition of steels was confirmed by X-ray diffraction analysis. Findings: The steels have a fine-grained austenite microstructure with many annealing twins to a temperature of about 1000°C. The initiation of dynamic recrystallization occurs already after true deformation equal 0.29. Participation of fine grains arranged in a matrix of dynamically recovered grains essentially increases after increasing true strain to 0.5. Fully dynamically recrystallized microstructure of steel can be obtained after the true strain equal 0.9. The conditions of hot-working influence phase state of investigated steels. Steel no. 1 keeps stable austenite microstructure independently from conditions of plastic deformation. Steel with initial bi-phase microstructure keeps a certain portion of ε martensite, yet dependant on conditions of hot-working. Research limitations/implications: To determine in detail the hot-working behaviour of developed steels, a progress of microstructure evolution in subsequent stages of multi-stage compression test should be investigated. Practical implications: The obtained microstructure- hot-working conditions relationships and stress-strain curves can be useful in determination of power-force parameters of hot-rolling for sheets with fine-grained austenitic structures. Originality/value: The hot-working behaviour and microstructure evolution in various conditions of plastic deformation for new-developed high-manganese austenitic steels with Nb and Ti microadditions were investigated.

Słowa kluczowe

EN

metallic alloys; high-manganese steels; hot-working; dynamic recrystallization; metadynamic recrystallization

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2008
• Tom: Vol. 31, nr 2
• Strony: 218--225
• Opis fizyczny: Bibliogr. 21 poz., wykr.

Twórcy

autor

Dobrzański L.

autor

Grajcar A.

autor

Borek W.

• Division of Materials Processing Technology, Management and Computer Techniques in Materials Science, Institute of Engineering Materials and Biomaterials, Silesian University of Technology, ul. Konarskiego 18a, 44-100 Gliwice, Poland,

Bibliografia

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