Selection of the hot-working conditions for TRIP-type microalloyed steel

• Autorzy: Grajcar A.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The aim of the paper is to develop hot-working conditions for a low-carbon Mn-Si-Al TRIP-type steel basing on axial compression tests. Design/methodology/approach: The influence of the austenitizing temperature on a grain size of austenite was determined on a basis of the dissolution kinetics in the austenite of MX-type interstitial phases. The identification of processes controlling the strain hardening was carried out in hot-compression tests. Specimens were deformed up to a true strain of 1.0 in a temperature range of 850 to 1150°C with strain rates of 0.1, 1.0 and 10s-¹. The σ-ε curves were useful for developing conditions of multi-stage axial compression. The plastic deformation was realized by the use of the DSI Gleeble 3800 equipment. Findings: It was found that the investigated steel has a fine-grained structure of austenite to a temperature of 1050°C. The obtained σ-ε curves indicate that used plastic deformation conditions influence substantially the εmax strain corresponding to a maximum value of flow stress. It increases with lowering the temperature of plastic deformation. The σ-ε curves obtained during multi-stage compression tests confirmed that under used conditions of temperature and strain a dynamic recovery is a process controlling the strain hardening in a whole strain range. Research limitations/implications: To design in detail hot-rolling conditions, the analysis of the influence of time between successive strains on a fraction of statically recrystallized austenite should be carried out. Practical implications: The obtained σ-ε curves are useful in determining force-energetic parameters of rolling and processes controlling the strain hardening during the hot-rolling. Originality/value: The determined true stress - true strain curves were obtained for the low-carbon TRIP-type steel containing Nb and Ti microadditions.

Słowa kluczowe

EN

metallic alloys; TRIP steel; hot compression test; dynamic recovery; dynamic recrystallization

PL

stopy metaliczne; stal TRIP; odkształcanie na gorąco; zdrowienie dynamiczne; rekrystalizacja dynamiczna

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2008
• Tom: Vol. 31, nr 2
• Strony: 75--78
• Opis fizyczny: Bibliogr. 15 poz.

Twórcy

autor

Grajcar A.

• Division of Constructional and Special Materials, Institute of Engineering Materials and Biomaterials, Silesian University of Technology, ul. Konarskiego 18a, 44-100 Gliwice, Poland,

Bibliografia

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