CASTING MATERIAL FOR INDEFINITE ROLLERS WITH A SLEEVE PART AND METHOD FOR PRODUCING THE SAME

摘要

The invention relates to a method for producing and processing casting materials for indefinite rollers with a sleeve part. The aim of the invention is to improve cast parts, especially rollers in the last stands of a strip rolling mill, in terms of their use-related properties and their service life. To this end, (A) the melt is produced with a chemical composition of the following in wt. % 2.0 to 3.5 C, 1.0 to 2.0 Si, 0.5 to 2.0 Mn, 1.0 to 3.0 Cr, 3.5 to 4.9 Ni and 0.2 to 2.9 Mo with the remainder being iron and impurities and (B) more than 0.5 wt.% and up to 5.9 wt.% vanadium is added and dissolved in this composition and (C) the composition of the melt is adjusted by alloy-technological means, by determining the concentrations of carbon, silicon, nickel and the effective sum of the carbide-forming elements, in such a way that when it hardens, the microstructure that forms has 1.0 to 3.0 vol. % graphite, on the condition that there are more than 20 graphite particles per mm<2> of observation surface of a metallographic section and that the remainder consists essentially of martensite, 8 to 35 vol. % eutectic carbides and at least 1 vol. % finely divided monocarbides, (D) the melt then being cast into a mould and allowed to harden into a body which is (E) subjected to a heat treatment.