Duisburg-Essen University (Duisburg, Germany):

Overhagen Ch., Mag. Sci., Scientifi c Fellow, Institute of Metal Technology, e-mail: christian.overhagen@uni-due.de
Mauk P. J., Dr. Eng., Institute of Metal Technology

Most processes of hot and cold rolling are limited because of the specific properties of rolls made of tungsten carbide and steel. An interesting alternative are ceramic materials because of their high wear resistance and resistance against mechanical loading, having a lower mass density at the same time. After research activities at the University of Duisburg-Essen, silicon nitride has proven to be an appropriate material for work rolls in rolling mills. The present paper gives an over-view about state-of-the-art knowledge and insights into future developments. It should be noted that change of work roll material will have corresponding sequences for the technological process. Increased elasticity module changes parameters of rolling stand springing. The developed integrated model for roll gap and location of work rolls has been presented for the thin strip cold rolling mill and it displays the eff ect of replacing steel work rolls by ceramic ones. Based on this model, calculations have been made; their results confirmed that usage of ceramic work rolls allows to provide better the required thickness deviations and needs less eff ect from the thickness adjustment system. It is concluded that these results can be used also for other rolling processes, e.g. in guiding rolls during hot rolling.

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