Hot-work die steel with good cutting performance and preparation method thereof

Abstract

The invention provides hot-work die steel with good cutting performance and a preparation method of the hot-work die steel. The die steel comprises the following components of, in percentage by weight, 0.28%-0.31% of C, 0.56%-0.70% of Si, 1.10%-1.20% of Mn, smaller than or equal to 0.020% of P, 0.01%-0.05% of S, 0.40%-0.80% of V, 7.00%-8.00% of Cr, 0.20%-1.00% of Ni, smaller than or equal to 0.01%of Alt, 0.10%-0.30% of Cu, and 0.01%-0.02% of Ca, and meanwhile, the content of gas in steel is required to meet the conditions that [O] is smaller than or equal to 20 ppm, [H] is smaller than or equal to 3 ppm, [N] is 80 ppm to 120 ppm, and the balance is Fe and inevitable impurities. The preparation method comprises smelting, large slab continuous casting, heating, rolling, pre-treatment, normalizing and tempering; and the hot-work die steel has the advantages of high machinability and high corrosion resistance, and is suitable for continuous casting large slab production.

Description

technical field [0001] The invention belongs to the field of metal materials, in particular to a hot work die steel with good cutting performance and a preparation method thereof. Background technique [0002] Hot work die steel is mostly used to manufacture high-temperature solid or high-temperature liquid metal pressing molds. Because of its excellent thermal strength, homogeneity and high polishing degree, it is more and more used in high-precision plastic molds. Because the working environment of such materials is generally harsh, the requirements for material composition, structure and application performance are extremely high. Affected by ingredients, usage methods and requirements, the cost is often high, and end users have very strict requirements for die steel. Compared with foreign advanced enterprises, there is a big gap in the stability of my country's materials. [0003] At present, hot work die steel products at home and abroad are mainly produced by forging ...

AI Technical Summary

Problems solved by technology

[0008] The above problems can be solved by using continuous casting process, but due to the high carbon and high alloy characteristics of hot work die steel products, it can only be used in the production of small flat steel. In addition, the high oxygen content and high sulfur content greatly reduce the surface tension of molten steel , so that the separation of steel slag is difficult, resulting in mixed rolls of steel slag, forming a large number of surface and subcutaneous defects, the risk of steel breakout is extremely high, and continuous casting production is difficult; due to the control of S, the manganese content in this type of steel is also very high. It will have physical and chemical reactions with some components in the refractory material, which will cause the refractory material to be corroded, and cause steel overflow or tundish leakage in continuous casting production; free-cutting steel liquid has high viscosity and poor fluidity. In order to ensure its Castability must increase the pouring temperature, and increasing the pouring temperature has limited influence on general materials, and it is very harmful to mold steel, a material with extremely high segregation

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