Microstructure investigation of low carbon steel after hot deformation

• Autorzy: Wolańska N. , Lis A. K. , Lis J.
• Konferencja: 12th International Scientific Conference CAM3S'2006, 27-30th November 2006, Gliwice-Zakopane
• Języki publikacji: EN

Abstrakty

EN

Purpose: Investigations of microstructure after hot deformation was presented in this work. The non-metallic inclusion influence on the microstructure and type of crack mechanism was shown. The hot ductility investigations were carried out on the low carbon-manganese steel with addition of boron. Design/methodology/approach: The ductility of the steel was measured by reduction of area during the extension test in the temperature range from 700 to 1200 degrees centigrade. The test was carried out with two different strain rates 0.01 s to the -1 and 6.5 s to the -1. The first one is characteristic for the continuous casting process and the second one for rolling of heavy plates and billets. The deformation microstructures of investigated steel after the hot extension tests were characterized by optical microscopy and scanning electron microscopy. The chemical composition of non-metallic inclusion was established by EDX analyses. Findings: The received - 30% ductility minimum of investigated steel with 0.01 s to the -1 strain rate, was found in the temperature range from 900 to 1000 degrees centigrade and these temperatures are connected with band straightening in the continuous casting process. The minimum of hot ductility for fast strain rate 6.5 s to the -1 reached -65% reduction of area value. The ferrite-bainite and ferrite-pearlite microstructures after air cooling were observed. The inclusions in different size from 0.6 to 4 micrometres and different shape (spherical and elongated) were observed. There were MnS and SiO2 inclusions with some other elements like Al2O3 and MnO. Practical implications: Low carbon steel with addition of boron is produced by continuous casting process where straightening of the strand is taken place close to 900 degrees centigrade. This temperature corresponds with hot ductility minimum for investigated steel. Originality/value: Available literature concerns investigations of low carbon steels but without boron addition, which expect to have strong influence on the position of the hot ductility minimum.

Słowa kluczowe

EN

ductility; hot ductility curves; low carbon steel; non-metallic inclusions

PL

plastyczność; ciągliwość; odkształcenie; temperatura; stal niskowęglowa; wtrącenia niemetaliczne

• Wydawca: International OCSCO World Press
• Czasopismo: Journal of Achievements in Materials and Manufacturing Engineering
• Rocznik: 2007
• Tom: Vol. 20, nr 1-2
• Strony: 291--294
• Opis fizyczny: Bibliogr. 17 poz., fot., rys., tab.

Twórcy

autor

Wolańska N.

autor

Lis A. K.

autor

Lis J.

• Institute of Materials Engineering, Faculty of Materials Processing Technology and Applied Physics, Częstochowa University of Technology, Armii Krajowej 19, 42-200 Częstochowa, Poland,

Bibliografia

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