Method for composite centrifugal casting high-chromium steel roller

Abstract

The invention relates to a method for a composite centrifugal casting high-chromium steel roller. The invention is characterized in that a semi-steel intermediate transition layer is arranged between a high-chromium working layer and a nodular-cast-iron core. The steel roller is produced through the following steps: smelting; modifying the semi-steel intermediate transition layer and the external high-chromium cast steel respectively, and nodulizing and inoculating melted iron used for preparing a nodular-cast-iron core; carrying out centrifugal casting; casting the nodular-cast-iron core; and cooling at room temperature and carrying out heat processing. The semi-steel intermediate transition layer comprises the following chemical components in percentage by weight: 1.0-2.2% of C, 0.4-1.5% of Si, 0.4-1.5% of Mn, 0-0.1% of P, 0-0.03% of S, 0-0.2% of Cr, 1.0-2.0% of Ni, 0.2-1.0% of Mo and the balance of Fe. The method provided by the invention has the beneficial effects that the bonding strength of the high-chromium working layer and the nodular-cast-iron core is enhanced, and occurrences of bonding-layer stripping and roller breakage accidents of the high-chromium composite cast steel roller are avoided.

Description

technical field [0001] The invention relates to the technical field of composite cast steel rolls, in particular to a method for composite centrifugally cast high-chromium steel rolls. Background technique [0002] At present, the methods of compound casting high chromium steel rolls mainly include molten iron metamorphism treatment, roll neck mold tooling preparation, cooling and unpacking, heat treatment, processing inspection and other processes. The common problem is that the outer high chromium cast steel and the core nodular cast iron The quality of the combination is difficult to guarantee. The outer layer of high chromium composite cast steel roll contains 10-15% chromium, while the core is ductile iron. The composition of the two materials is very different, and the outer layer with high chromium content The layer must form a large amount of carbides with the carbon in the core ductile iron to exist in the bonding layer, so that the strength of the bonding layer is ...

AI Technical Summary

Problems solved by technology

[0002] At present, the methods of compound casting high chromium steel rolls mainly include molten iron metamorphism treatment, roll neck mold tooling preparation, cooling and unpacking, heat treatment, processing inspection and other processes. The common problem is that the outer high chromium cast steel and the core nodular cast iron The quality of the combination is difficult to guarantee. The outer layer of high chromium composite cast steel roll contains 10-15% chromium, while the core is ductile iron. The composition of the two materials is very different, and the outer layer with high chromium content The layer must form a large amount of carbides with the carbon in the core ductile iron to exist in the bonding layer, so that the strength of the bonding layer is very low, and it is easy to cause peeling accidents of the roll bonding layer during use; on the other hand, due to the high chromium in the outer layer It is difficult to solve the problem that the content diffuses to the core and reduces the strength of the roll neck

When composite casting high-chromium steel rolls, when the outer layer is solidified and the core ductile iron molten iron is cast, the cast core ductile iron molten iron will remelt part of the solidified outer high-chromium cast steel, causing the high-chromium content to core. Diffusion in the core will increase the chromium content in the core, and the whitening tendency of the core will increase, so that more carbides will be precipitated, which will affect the overall strength of the roll, and roll breakage accidents will easily occur when the roll is in use.