High-toughness high-speed steel composite roll

Abstract

The invention discloses a high-toughness high-speed steel composite roll belonging to the technical field of metal pressure processing. A working layer of the roll is made of a high-toughness high-speed steel material, and the core part of the roll is made of a graphitic steel material; the high-speed steel material and the graphitic steel material are in metallurgical bonding and formed through centrifugally casting and compounding. The high-speed steel material comprises the chemical components in percentage by weight: 0.5-1.3% of C, 0.5-1.5% of Si, 0.4-1.0% of Mn, 5.0-10.0% of Cr, 2.0-5.0% of Mo, 0.5-1.5% of Ni, 0.1-2.0% of W, 0.1-2.0% of V, 0.05-0.6% of N, 0.01-0.5% of RE, less than 0.03% of R, less than 0.025% of S and the balance of Fe; the graphitic steel material comprises the following chemical components in percentage by weight: 1.2-2.0% of C, 1.5-2.5% of Si, 0.3-1.0% of Mn, 0.2-1.2% of Ni, 0.01-0.2% of Cr, 0.01-0.2% of Mo, less than 0.035% of P, less than 0.03% of S and the balance of Fe. The high-toughness high-speed steel composite roll has the advantages that the breakage of the roll in the production process is reduced, the rate of finished products is increased, the manufacturing cost of the roll is reduced, the online service time of the roll is prolonged, the operating rate of a rolling mill is increased, and the consumption of the roll is reduced.

Description

technical field [0001] The invention belongs to the technical field of metal pressure processing, and in particular provides a high-toughness high-speed steel composite roll, which is suitable for manufacturing the composite roll in the steel rolling industry. Background technique [0002] Rolling mill is an important equipment in metal pressure processing and production, and it is a remarkable symbol to measure the technical level of a country's steel development. The roll is the main component of the rolling mill, a key component consumed in large quantities in rolling steel production, and a basic guarantee for determining the development level of a country's rolling technology. In the production of steel rolling industry, every rolling material depends on the roll. It is formed by rolling, that is to say "no roll, no material", so the quality and function of the roll are very important. In 2012, the output of wire and bar in my country alone reached 385.64 million tons....

AI Technical Summary

Problems solved by technology

But the density of metal W is 19.3kg / dm 3 , W 2 The density of C is 17.2kg / dm 3 , the density of WC is 15.8kg / dm 3 , under the action of centrifugal force, metal elements and structures are segregated and gathered in the working layer near the roll surface; the density of metal V is only 6.1kg / dm 3 , the density of VC is only 5.7kg / dm 3 , Under the action of centrifugal force, it also causes metal elements and structures to segregate and gather in the working layer near the bonding layer, making the distribution of different types of metal elements and carbide structures uneven, resulting in a sharp decline in the toughness of high-speed steel materials and uneven

[0006] At the same time, in the implementation of the existing high-speed steel roll production technology, when pouring the nodular cast iron liquid in the core of the roll, the inner surface of the solidified high-speed steel layer of the working layer must be melted to a certain depth, and the melted part of the high-speed steel Due to the segregation of metal elements and structures, it contains a large amount of strong carbide-forming element V. After the V element enters the ductile iron molten iron at the core of the roll, the higher C content in the molten iron makes the amount of carbides in the ductile iron structure at the core of the roll sharply increased, and even increased to more than 20%, which caused a significant reduction in the strength of the roll bonding layer and the roll core

In particular, during the heat treatment process of the rolls containing this bonding layer, the rolls are often broken due to insufficient strength at the bonding layer or the core of the rolls, which reduces the production yield of the rolls, and the production cycle cannot be guaranteed. As a result, the manufacturing cost of the roll is greatly increased

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