Influence of hot and warm deformation on austenite decomposition

• Autorzy: Jandová D.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The substructure of austenite influences phase transformations during the austenite decomposition and consequently the final properties of the steel. Design/methodology/approach: Steel 0.5C-1Cr-0.8Mn-0.3Si was processed using the thermo-mechanical cycling simulator. Different methods of the thermo-mechanical processing were applied including austenitization at 950°C, compression deformation at 950°C or 650°C and isothermal dwell at temperatures in the range (350°C÷450°C). Microstructure was investigated using light and transmission electron microscopy. Findings: It was demonstrated that straining in austenitic region accelerated the ferrite and pearlite transformations. Bainite reaction depended on the temperature of austenite deformation, the strain level and the temperature of isothermal dwell. Hot deformation slightly accelerated the transformation to upper bainite and retarded the transformation to lower bainite. Warm deformation resulted in mixture structures containing pearlite, ferrite and bainite; bainitic reactions were accelerated. Fine ferritic grains, pearlitic nodules and clusters of individual ferrite/carbide units enclosed with martensitic matrix were observed in heavy strained parts of specimens. Practical implications: Different morphologies of ferritic structures which can occur in the wrought steel can result in deterioration of mechanical properties. This fact has to be taken into account in numerical simulations of thermo-mechanical processing of low alloy steels. Originality/value: Of this paper consists in elucidation of the processes taking place in heavy strained austenitic structure during its isothermal decomposition at temperatures in bainitic region.

Słowa kluczowe

EN

heat treatment; metallic alloys; electron microscopy; metallography

PL

obróbka cieplna; stopy metali; mikroskopia elektronowa; metalografia

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2006
• Tom: Vol. 18, nr 1-2
• Strony: 375--378
• Opis fizyczny: Bibliogr. 16 poz., rys., wykr.

Twórcy

autor

Jandová D.

• Department of Material Science and Engineering Metallurgy, University of West Bohemia in Pilsen, Univerzitní 8, CZ-306 14 Pilsen, Czech Republic

Bibliografia

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