Spray quenching process for alloy semi-steel roll

Abstract

The invention discloses a spray quenching process for an alloy semi-steel roll. The process includes the following steps that the alloy semi-steel roll is heated to the temperature ranging from 600 DEG C to 620 DEG C; mixed liquid of castor oil and absolute ethyl alcohol is sprayed to a roll body and the roll body is rotated clockwise at the speed ranging from 20 r / min to 30 r / min in the spraying process; after the temperature is kept for 4 h to 6 h, rotation of the roll body is stopped, and the temperature is increased to 730 DEG C to 750 DEG C at the temperature increase speed of 50 DEG C / h to 60 DEG C / h; and after the temperature is kept for 7 h to 10 h, the roll body is rotated anticlockwise at the speed ranging from 10 r / min to 15 r / min in, the surface of the roll body is scoured for 30 min to 40 min through atomized water and wind, and the roll body is subjected to furnace cooling till the temperature of the roll body is 150 DEG C, wherein atomized water and the wind are formed by compressed gas blown to a water column and the angle between the water column and the roll body ranges from 10 degrees to 30 degrees. The process has the beneficial effects that a certain carburization body type Widmannstatten structure in a matrix structure of the roll body of the alloy semi-steel roll is reserved, and the abrasion resistance of the roll is improved; and heavy vapor and dry ice particles are added to the compressed gas, so that the cooling speed of the surface of the roll is increased, and the mechanical performance index of the roll body is increased.

Description

Technical field [0001] The invention relates to a heat treatment process of an alloy half-steel roll, in particular to a spray quenching process of an alloy half-steel roll. Background technique [0002] The carbon content of alloy semi-steel rolls usually fluctuates in the range of 1.4-2.3%, and the mechanical properties are between steel and iron. This kind of roll has the characteristics of small hardness drop and high wear resistance. It is widely used to replace cast steel rolls and ordinary low-alloy cast iron rolls. It is used for rough rolling and intermediate rolling stands of section steel rolling mills, rough rolling and finishing of hot strip continuous rolling mills. Work roll before rolling. [0003] After the alloy semi-steel rolls are demolded, most of them undergo heat treatments such as high temperature diffusion annealing, spheroidizing annealing, normalizing and tempering; or after spheroidizing annealing, the working layer of the roll body is quickly heated an...

AI Technical Summary

Problems solved by technology

[0004] There are two problems in the existing spray quenching process. First, it will eliminate or reduce the cementite-type Widmanstatten structure in the matrix structure of the alloy semi-steel roll, and for the alloy semi-steel used in the front section of the hot strip continuous rolling mill For steel work rolls, when the thin strip or rod proeutectoid carbide-type Widmanstatten structure in the working layer matrix structure of the roll body is reduced, not only the wear resistance of the roll will be significantly reduced, but also the surface of the steel strip and the roll body will occur. Bonding phenomenon, with the bonding of the steel strip and the surface of the roll body, thermal cracks will inevitably occur on the surface of the roll body, thereby increasing the grinding amount of the roll body and reducing the service life of the roll; the second spray quenching Although the cooling rate is better than oil cooling and water cooling, the cooling rate is still not fast enough, and the mechanical properties of the surface of the roll body are not good enough