High-alloy centrifugal compound cast steel supporting roll and manufacturing technology thereof

Abstract

The invention relates to a high-alloy centrifugal compounding steelcasting support roll and a processing technique thereof. The high-alloy centrifugal compounding steelcasting support roll comprises the following chemical substances: a working layer containing 0.4-0.5 of C, 0.3-0.6 of Si, 0.4-0.8 of Mn, less than or equal to 0.035 of P, less than or equal to 0.03 of S, 3.5-4.5 of Cr, 0.2-1.0 of Ni and 0.2-0.5 of Mo, and the balance steel and impurities by weight; a core part containing 3.0-3.6 of C, 1.7-2.7 of Si, 0.2-1.0 of Mn, less than or equal to 0.08 of P, less than or equal to 0.01 of S, 0.01-0.04 of Re, 0.03-0.08 of Mg, less than or equal to 1.0 of Cr, less than or equal to 1.0 of Ni, less than or equal to 1.0of Mo, less than or equal to 1.0 of Cu, less than or equal to1.0 of V, and the balance iron and impurities by weight. Furthermore, the working layer is formed by horizontal type centrifugal pouring, the core part is formed by pouring, and the heat treatment is carried out in such a way that a trolley type high-temperature resistance furnace to heat a rough machining support roll in an austenite way and preserve the heat of the rough machining support roll. The invention has high abrasion resistance, high accident prevention and high working production ratio.

Description

technical field [0001] The invention relates to a backup roll used in wide-band, medium-wide-band and narrow-band continuous rolling mills and a manufacturing method of the backup roll, in particular to a high-alloy centrifugal composite cast steel backup roll and its manufacturing process. Background technique [0002] At present, the back-up rolls of wide-band and medium-broad continuous rolling mills are usually cast with alloy semi-steel materials, or remanufactured from scrapped integral forged steel rolls; the back-up rolls of narrow-band continuous rolling mills are generally made of alloy semi-steel composite casting. When these backup rolls are used online, there are generally destructive failure forms such as shoulder off, spalling, cracks, and broken rolls, resulting in increased roll consumption and reduced production efficiency. The reason for these phenomena is that the metallographic structure of these back-up roll materials is characterized by the presence of...

AI Technical Summary

Problems solved by technology

When these backup rolls are used online, there are common destructive failure forms such as shoulder off, spalling, cracks, and roll breakage, resulting in increased roll consumption and reduced production efficiency.

The reason for these phenomena is that the metallographic structure of these back-up roll materials is characterized by the presence of a large amount of M in the metallographic structure 3 C-type carbide, the matrix is ​​generally pearlite or tempered sorbite depending on the heat treatment system. This metallographic structure has poor mechanical properties and high brittleness, and its mechanical properties and contact fatigue resistance cannot meet the needs of backup rolls. The technical requirements, in the process of use can not resist the strong rolling force, the service life is short

Moreover, the existing backup roll manufacturing process adopts vertical centrifugal casting, which requires large equipment investment and low process yield, which brings a large economic burden to the enterprise.

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