Influence of a matrix on properties of mottled cast iron applied for mill rolls

• Autorzy: Krawczyk J. , Pacyna J.
• Języki publikacji: EN

Abstrakty

EN

Mill rolls are ones of the most expensive tools applied in plastic working processes and have to satisfy several criteria, which allow them to be used. Cast iron mill rolls, due to their fracture toughness and tribological properties, are the most often applied at hot-rolling in the last rolling stands. This results from the smallest dynamic loads of such rolling stands and the decisive influence of the surface quality of these tools on the surface quality of the rolled product. An improper microstructure of rolls can lead to their premature wearing, e.g. broken flanges, pivots twisting off etc. By means of the heat treatment the matrix microstructure and morphology of carbide precipitations can be modified and this in-turn can influence cast iron properties. Determination of the influence of microstructure changes, caused by the heat treatment, on the properties of EN-GJN-HV300 low-alloy cast iron, after its modification and spheroidization – is the aim of the present paper. Those changes are based on the formation pearlitic or bainitic matrices at the similar morphology of graphite and ledeburitic cementite precipitations. The performed investigations should enable designing the heat treatment of cast iron metallurgical rolls in such a way as to obtain the optimal microstructures for functional parameters of these type of tools. The influence of changing the pearlitic matrix into the bainitic one on such properties as: hardness, impact strength, tensile strength, creep limit, bending strength and a stress intensity factor K_Ic was investigated in this study. Samples for testing, the listed above mechanical properties, were taken from an industrial casting with care to have pieces of very similar crystallization conditions.

Słowa kluczowe

EN

wear resistant alloys; mill rolls; heat treatment; cast iron; bainite; pearlite

PL

stopy odporne na ścieranie; walce hutnicze; obróbka cieplna; żeliwo; perlit

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2010
• Tom: Vol. 10, iss. 3
• Strony: 45--50
• Opis fizyczny: Bibliogr. 25 poz., il., tab.

Twórcy

autor

Krawczyk J.

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

autor

Pacyna J.

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

Bibliografia

• [1] J. Krawczyk, Structural causes of defects in a cast iron mill roll, Archives of Foundry Engineering, vol. 8, No. 2 (2008) 93-98.
• [2] J. Krawczyk, Effect of the microstructure on tribological phenomena occurring on the surface of a mill roll made of SA5T cast iron (GJSL-HV600 – GJSL-330NiMoCr12-8-3), Archives of Foundry Engineering, Vol. 8, No. 2 (2008) 170-174.
• [3] J. Krawczyk, J. Pacyna, A. Kokosza, Fracture toughness of cast materials for mill rolls, Proceedings of the 6th International Conference for Mesomechanics, Multiscaling in Applied Science and Emerging Technology, Fundamentals and Applications in Mesomechanics, 31 May - 4 June, 2004, Patras, Greece, s. 203-207.
• [4] J. Krawczyk, J. Pacyna, The influence of microstructure of mottled cast iron for mill rolls on its properties, Metal 2009 – 18th International Conference on Metallurgy and Materials, May 19th-21st, 2009, Hradec - Moravicy, Czech Republic, 266-272.
• [5] J.J. Coronado, A. Gómez, A. Sinatora, Tempering temperature effects on abrasive wear of mottled cast iron, Wear, vol. 267 (2009) 2070-2076.
• [6] E. Rożniata, J. Pacyna, Structure of chromium-nickelmolybdenum cast steel after additional heat treatment, Archives of Foundry Engineering, Vol. 6, no. 21(1/2) (2006) 85-92 (in Polish).
• [7] D. Kopyciński, Inoculation of chromium white cast iron, Archives of Foundry Engineering, Vol. 9, no. 1 (2009) 191-194.
• [8] E. Fraś, M. Kawalec, Effect of silicon on the structure and mechanical properties of high-vanadium cast iron, Archives of Foundry Engineering, Vol. 9, No. 3 (2009) 231-134.
• [9] E. Fraś, M. Kawalec, Effect of small additions of vanadium and niobium on structure mechanical properties of nodular cast iron, Archives of Foundry Engineering, Vol. 6, no. 21(1/2) (2006) 383-388 (in Polish).
• [10] E. Guzik, Some selected problems concerning the processes of cast iron improvement, Archives of Foundry Engineering, 2001, Monograph No. 1M (in Polish).
• [11] M. Kawalec, E. Fraś, Abrasive wear resistance of high vanadium cast iron, Archives of Foundry Engineering, Vol. 9, No. 4 (2009) 103-108.
• [12] G. Pintaude, F.G. Bernardes, M.M. Santos, A. Sinatora, E. Albertin, Mild and severe wear of steels and cast irons in sliding abrasion, Wear, Vol. 267 (2009) 19-25.
• [13] S. Rzadkosz, L. Staszczak, High chromium cast iron for impellers of shot blasing machines, Archives of Foundry, Vol. 6, no 21(1/2) (2006) 71-78 (in Polish).
• [14] D.N. Hanlon, W.M. Raiforth, C.M. Sellars, The rolling/sliding wear response of conventionally processed and spray formed high chromium content cast iron at ambient and elevated temperature, Wear, vol. 225-229 (1999) 587-599.
• [15] E. Rożniata, J. Pacyna, Effect of annealing on mechanical properties of ledeburitic cast steel, Journal of Achievements in Materials and Manufacturing Engineering, vol. 20, No. 1-2 (2007) 187-190.
• [16] E. Rożniata, J. Pacyna, Effect of structure on mechanical properties of Cr-Ni-Mo cast steel, Archives of Materials Science and Engineering, vol. 28, No. 4 (2007) 224-230.
• [17] E. Rożniata, J. Pacyna, Hypereutectoid cementite morphology and mechanical properties of Cr-Ni-Mo cast steel, Journal of Achievements in Materials and Manufacturing Engineering, vol. 17, No. 1 (2006) 145-148.
• [18] J. Krawczyk, E. Rożniata, J. Pacyna: The influence of hypereutectoid cementite morphology upon fracture toughness of chromium-nickel-molybdenum cast steel of ledeburite class, J. of Materials Processing Technology, vol. 162-163 (2005) 336-341.
• [19] Y. Taşgin, M. Kaplan, M. Yaz, Investigation of effects of boron additives and heat treatment on carbides and phase transition of highly alloyed duplex cast iron, Materials and Design, vol. 30 (2009) 3174-3179.
• [20] A. Akdemir, R. Kuş, M. Şimşir, Impact toughness and microstructure of continuous steel wire-reinforced cast iron composite, Materials Science and Engineering A, vol. 516 (2009) 119-125.
• [21] D. Li, L. Liu, Y. Zhang, Ch. Ye, X. Ren, Y. Yang, Q. Yang, Phase diagram calculation of high chromium cast irons and influence of its chemical composition, Materials and Design, vol. 30 (2009) 340-345.
• [22] A. Vadiraj, G. Balachandran, M. Kamaraj, B. Gopalakrishna, K. Prabhakara Rao, Studies on mechanical and wear properties of alloyed hypereutectic gray cast iron in the as-cast pearlitic and austempered conditions, Materials and Design, vol. 31 (2010) 951-955.
• [23] N. Fatahalla, A. Abu El Ezz, M. Semeida, C, Si and Ni as alloyng elements to vary carbon equivalent of austenitic ductile cast iron: Microstructure and mechanical properties, Materials Science and Engineering A, vol. 504 (2009) 81-89.
• [24] J. Wang, J. Xiong, H. Fan, H.-H. Liu, B.-L. Shen, Effects of high temperature and cryogenic treatment on the microstructure and abrasion resistance of a high chromium cast iron, J. of Materials Processing Technology, vol. 209 (2009) 3236-3240.
• [25] R. Correa, A. Bedolla-Jacuinde, J. Zuno-Silva, E. Cardoso, I. Mejía, Effect of boron on the sliding wearm of directionally solidified high-chromium white irons, Wear, 267 (2009) 495-504.