Method for compositely centrifugal pouring high chromium centrifugal composite cast iron roll with alloy semisteel intermediate layer

Abstract

The invention relates to a composite cast iron roll technology field, in particular to a method for using alloy semi-steel middle transition layer composite centrifugation to cast high chromium double composite cast iron roll, which includes the following process steps: respectively melting the steel water in the transition layer of the alloy semi-steel, external high chromium casting iron melting and core ball graphite casting iron melting; conducting modification treatment to the steel water in the transition layer in the middle of the alloy semi-steel and the steel water of the external high chromium casting iron and conducting spheroidization and inoculation treatment to the core ball graphite casting iron steel water, and adopting the centrifugation casting method to cast high chromium casting steel and the steel water in the transition layer of the alloy semi-steel; preparing fixture and mould closing; casting core ball graphite casting steel water with static casting method; cooling and opening box, conducting heat treatment and processing inspection. The component weight percentage of the steel water in the middle transition layer of the alloy semi-steel is: C 1.4 to 2.6, Si 1.0 to 2.0, Mn 0.5 to 1.5, P being less than 1.0, S being less than 0.03, Cr 3 to 8, Ni 0.5 to 1.5 and Mo 0.5 to 1.5. The structure layer and the core strength of the roll are respectively over 320MPa and 400MPa, thus the performance being very safe and reliable.

Description

technical field [0001] The invention relates to the technical field of composite cast iron rolls, in particular to a method for composite centrifugal casting of high-chromium double composite cast iron rolls with an alloy semi-steel intermediate transition layer. Background technique [0002] The method for composite casting high chromium double composite cast iron roll includes molten iron modification treatment, tooling preparation for roll neck mold, cooling and unpacking, heat treatment, and processing inspection. When composite casting high-chromium double-composite cast iron rolls, it is difficult to guarantee the bonding quality between the outer high-chromium cast iron and the core nodular cast iron. During composite casting, the outer high chromium composite cast iron roll working layer contains 17-22% chromium, while the core is nodular cast iron. The carbon in the nodular cast iron forms a large number of carbides in the bonding layer, making the bonding layer ve...

AI Technical Summary

Problems solved by technology

When compound casting high chromium double composite cast iron rolls, it is difficult to guarantee the bonding quality between the outer high chromium cast iron and the core nodular cast iron

During composite casting, the outer high chromium composite cast iron roll working layer contains 17-22% chromium, while the core is nodular cast iron. The carbon in the nodular cast iron forms a large number of carbides in the bonding layer, making the bonding layer very low in strength, and it is easy to cause the roll bonding layer to peel off during use; on the other hand, due to the high chromium content in the outer layer diffusing to the core However, the problem of reducing the strength of the roll neck is difficult to solve

When composite casting high chromium composite cast iron 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 layer high chromium cast iron, 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.