The paper presents a new approach to interpretation of hypoeutectoid steel dilatograms upon heating between the austenite start and austenite finish temperatures. The proposed derivative curve separation method yields data which accords with the experimental results. Besides the new method appears a useful tool whereby it becomes possible to confirm the evidence reported earlier in literature that when a hypoeutectoid steel heats up to between the A1 and the A3 both ferrite and pearlite start to transform into austenite almost at the same time.
 M. Philip, W. Bo1ton, Technology of Engineering Materials, Ed. Butterworth Heinemann, London 2002.
 G. Krauss, Steels: Processing, structure and performance. ASM International 2005.
 M. Mehta, T. Oakwood, Development of a Standard Methodology for the Quantitative Measurement of
Steel Phase Transformation Kinetics and Dilation Strains using Dilatometric Methods (QMST), Final Report. US Department of Energy, Prepared by American Iron and Steel Institute Technology Roadmap Program, Office Pittsburgh, PA 15222 (2004).
 B. Pawłowski, P. Bała, J. Krawczyk, Some factors influencing the determination of eutectoid start and finish temperatures in hypoeutectoid steels. Metallurgy and Foundry Engineering MaFE 35, 2, 121-128 (2009).
 T. Schmidt, Y. Wang, S. Sridhar, A study of nonisothermal austenite formation and decomposition in Fe-C-Mn alloys. Metallurgical and Materials Transactions A 37, 1799-1810 (2006).
 S-J. Lee, K.D. Clarke, C.J. Van Tyne, An on-heating dilation conversional model for austenite formation in hypeutectoid steels. Metallurgical and Materials Transactions A 41, 2224-2235 (2010).
 D. San Martin, P.E.J. Rivera Diaz del Castillo, C. Garcia de Andres, In situ study of austenite formation by dilatometry in a low carbon microalloyed steel. Scripta Materialia 58, 926-929 (2008).
 N.T. Egorov, Peculiarities of austenitization of the low-carbon steels during heat treatment of plates in-line of the rolling mills. Proc. 11th Metallurgical and Material Conf., 2002, Hradec nad Maravici, Czech Republic, paper no 105.
 D. San Martin, T. de Cock, Garcia-Junceda, F.G. Caballero, C. Capdevila, C. Garcia de Andres, Effect of heating rate on reaustenitisation of low carbon niobium microalloyed steel. Materials Science and Technology 24, 3, 266-272 (2008).