RAUDENSKÝ Miroslav Brno University of Technology

Spoluautoři CHABIČOVSKÝ Martin, HRABOVSKÝ Jozef

Oxidation is inherent part of steel production and heat treatment. The most common impact of the oxide scale layers is on the surface quality and material losses during steel processing. This paper is focused on study of influence of the oxide layer on cooling intensity. Spray cooling of hot steel surface is considered. Typical example is secondary cooling in continuous casting, interstand and run-out table cooling at hot rolling and heat treatment and other metallurgical processes where controlled temperature regimes are required. Cooling intensity is primarily affected by spray parameters as pressure and coolant impingement density. It is not frequently reported but even thin layers of oxides can significantly modify the cooling intensity. This effect is dominant in the cooling of steel surfaces at high surface temperatures. Study of the influence of the oxide scale layers on cooling intensity was carried out by experimental measurements and numerical analysis. Experimental measurements compare the cooling of scale-free surfaces and oxidized surfaces. Experimental investigations show a difference in the cooling intensity. Numerical analyses were prepared to simulate cooling of the samples with different oxide scale layers and different thermal conductivity of scales. Even a scale layer of several microns can significantly modify the cooling intensity.