The influence of continuous heating rate on the austenite formation in the medium carbon TRIP steel

• Autorzy: Kokosza A. , Pacyna J. , Bała P. , Dziurka R.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The purpose of the hereby work was to determine the influence of heating rate on the austenite formation range and to draw the time-temperature-austenitizing diagram at continuous heating for TRIP 41MnSi6-5 steel. Design/methodology/approach: The dilatometric analysis was applied as the basic investigation method. Samples of the tested steel were heated to 1100°C with various heating rates. Changes in the relative elongation (ΔL) were recorded as a temperature function (T), during heating. On the basis of analysing such dependencies, for each heating rate the critical temperatures were determined. Findings: It was found, that during heating of the 41MnSi6-5 steel the austenite formation starts at the higher temperature the faster is the heating. It was observed, that directly before the start of the austenite formation, an unidentified (in the presented here investigations) transformation occurs in the investigated steel, causing its volume increase. Research limitations/implications: The performed investigations indicate that during heating of elements of small thickness or cross-sections - within the critical temperature range - the method of their heating to the required temperature becomes very important. At short heating times incorrectly selected the heating conditions can be the reason of significant errors of the heat treatment. Practical implications: The developed diagram: time-temperature-austenitizing, at a continuous heating (CHT), can be a useful tool supporting the proper selection of heating parameters within the critical temperature range. Originality/value: The dependence of the heating rate and the temperature range, in which austenite is formed in the tested 41MnSi6-5 steel, was found. It was observed that heating of the investigated steel with rates lower than 1°C/s has an insignificant influence on the temperature range within which the austenite formation occurs.

Słowa kluczowe

EN

dilatometric analysis; CHT diagrams; heat treatment; critical temperatures; TRIP steels

PL

analiza dylatometryczna; wykres CHT; obróbka cieplna; temperatura krytyczna; stal TRIP

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2013
• Tom: Vol. 62, nr 1
• Strony: 22--27
• Opis fizyczny: Bibliogr. 20 poz.

Twórcy

autor

Kokosza A.

• Faculty of Metals Engineering and Industrial Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, 30-059 Kraków, Poland

autor

Pacyna J.

• Faculty of Metals Engineering and Industrial Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, 30-059 Kraków, Poland

autor

Bała P.

• Faculty of Metals Engineering and Industrial Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, 30-059 Kraków, Poland

autor

Dziurka R.

• Faculty of Metals Engineering and Industrial Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, 30-059 Kraków, Poland

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