Influence of hot-working conditions on a structure of high-manganese austenitic steels

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

Abstrakty

EN

Purpose: The aim of the paper is to determine the influence of hot deformation conditions on σ - ε curves and structure changes of new-developed high-manganese austenitic steels. Design/methodology/approach: The force-energetic parameters of hot-working were determined in hot-compression tests performed in a temperature range of 850 to 1050° C by the use of the Gleeble 3800 thermomechanical simulator. Evaluation of processes controlling work hardening at 850° C were identified by microstructure observations of the specimens water-quenched after plastic deformation to a true strain equal 0.22, 0.51 and 0.92. Findings: At initial state the steel containing 3% of Si and Al possesses homogeneous austenite structure with many annealing twins. Increased up to 4% Si concentration and decreased to 2% Al concentration result in a presence of some fraction of ε martensite plates. For applied deformation conditions, the values of flow stress vary from 250 to 450MPa - increasing with decreasing deformation temperature. A relatively small values of ε max deformation at temperatures of 1050 and 950° C allow to suppose that in this range of temperature, to form a fine-grained microstructure of steels, dynamic recrystallization can be used. At a temperature of 850° C, the dynamic recrystallization leads to structure refinement after true strain of about 0.51. Research limitations/implications: To determine in detail the hot-working behaviour of developed steels, a progress of recrystallization as a function of time at deformation temperature should be investigated. Practical implications: The obtained stress-strain curves can be useful in determination of power-force parameters of hot-rolling of high-manganese austenitic steels. Originality/value: The hot-working behaviour of new-devoloped high-manganese austenitic steels containing Nb and Ti microadditions was investigated.

Słowa kluczowe

PL

stopy metaliczne; obróbka cieplna; rekrystalizacja dynamiczna; rekrystalizacja metadynamiczna

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. 29, nr 2
• Strony: 139--142
• Opis fizyczny: Bibliogr. 15 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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