Tertiary Scale Behaviour during Finishing Hot Rolling of Steel Flat Products

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Steel strip surface oxidation during hot mill processing represents an industrial and environmental problem: secondary oxide is removed after roughing, but tertiary oxide scales already start to form before entering the finishing stands. Their properties affect the final steel surface quality and its response to further processing. Controlling the oxide layer growth kinetics and mechanical properties can make pickling easier and improve downstream behaviour. A thin wustite-dominated scale layer (<20 μm) is created under controlled conditions in an original laboratory device adequately positioned in a compression test machine to investigate plane strain compression. A first series of oxidation tests were performed on a ULC steel grade to measure the kinetics of oxide scale growth. The samples were first heated up under a protective atmosphere (nitrogen), before being oxidised in air at different temperatures for various oxidation times. These experiments can be considered fair quantitative and qualitative simulations of scale growth as it occurs in a hot strip mill, insofar as the results thus obtained are in good agreement with the literature. After the oxide growth, plane strain compression (PSC) was performed immediately to simulate the hot rolling process. The oxide layers were characterised before and after compression tests by optical and secondary electron microscopy. As expected, the oxide is seen to deform during compression. The obtained oxide layers exhibit good adhesion to the substrate and homogeneity over the thickness, even after compression.

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Periodical:

Advanced Materials Research (Volumes 15-17)

Edited by:

T. Chandra, K. Tsuzaki, M. Militzer and C. Ravindran

Pages:

732-737

Citation:

L. Suárez et al., "Tertiary Scale Behaviour during Finishing Hot Rolling of Steel Flat Products", Advanced Materials Research, Vols. 15-17, pp. 732-737, 2007

Online since:

February 2006

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$38.00

[1] M. H. Davies, M. T. Simnad and C. E. Birchenall, On the mechanism and kinetics of the scaling of iron, Journal of metals (1951), pp.889-896.

[2] P. Kofstad, High Temperature Corrosion, Elsevier Applied Science Publishers, London (1988).

[3] Y. Hidaka, T. Anraku, N. Otsuka, Deformation of iron oxides upon tensile tests at 600- 1250°C, Oxidation of Metals, vol 59, 1-2, February (2003).

[4] J. Païdassi, Sur la cinétique de l'oxydation du fer dans l'air dans l'intervalle 700-1250°C, Acta Metallurgica 6 (1958) pp.184-194.

DOI: https://doi.org/10.1016/0001-6160(58)90006-3

[5] D. Filatov, O. Pawelski, W. Rasp, Hot-rolling experiments on deformation behaviour of oxide scale, Steel Research Int. 75 (2004) pp.20-25.

DOI: https://doi.org/10.1002/srin.200405921

[6] M. S. Loveday, G. J. Mahon, B. Roebuck, C. M. Sellars and M. R. van der Winden, Measuring flow stress in plane strain compression tests, Measurement Good Practice Guide No 27.

[7] W. Sun, A.K. Tieu, Z. Jiang, H. Zhu and C. Lu, Oxide scale growth of low-carbon steel at high temperatures, Journal of Materials Processing Technology (2004), Vol. 155-156, pp.1300-1306.

DOI: https://doi.org/10.1016/j.jmatprotec.2004.04.172

[8] M. S. Mirza and C. M. Sellars, Modelling the hot plane strain compression test, Part I- Effect of specimen geometry, strain rate, and friction on deformation, Materials Science and Technology 17 (2001) pp.1133-1141.

DOI: https://doi.org/10.1179/026708301101511068

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