Near-net-shaped manufacturing method of difficult-to-machine material

Abstract

The invention relates to a near-net-shaped manufacturing method of a difficult-to-machine material. The method comprises the following steps of: continuous casting, cooling, conveying, rolling and packaging. According to the invention, the continuous casting, the hot rolling, heat treatment and the cold rolling and other processes are integrated, continuous casting and rolling of a thin strip are performed by a reversible rolling machine set with hot, warm and cold three-rolling modes under the protection of gas, in this way, the surface of the strip is prevented from being oxidized in the production process, the one-step forming from molten steel to a cold rolled product is realized, the production process is greatly simplified, the important processes such as hot continuous rolling, acid-washing process and the like are omitted, and thus, the technical layout from smelting to cold rolling the finished product is shortened from thousands of meters to hundreds of meters, and the production cycle is shortened from at least three days to less than three hours, the weight of an apparatus is reduced by more than 90%, and thus, a novel way is provided for the new metal material development. The method further has the advantages of increasing the yield and reducing the environment pollution.

Description

technical field [0001] The invention relates to material processing and manufacturing, in particular to a near net forming manufacturing method of difficult-to-machine materials. Background technique [0002] Difficult-to-process special alloy steels are characterized by complex phase transitions in the solidification process and the formation of hard and brittle structures. Continuous casting, forging, rolling, and forming are all very difficult, and the yield is very low. Especially for high-silicon electrical steel, the higher the silicon content, the better the magnetic permeability, but with the increase of silicon content, the plasticity of the material is greatly reduced, the material becomes brittle, difficult to coil, difficult to uncoil, and more difficult to process. [0003] The technology that adopts the industrialization of material near-net forming manufacturing technology, such as the Castrip twin-roll thin strip production line in the United States, the twin...

AI Technical Summary

Problems solved by technology

[0002] Difficult-to-process special alloy steels are characterized by complex phase transitions in the solidification process and the formation of hard and brittle structures. Continuous casting, forging, rolling, and forming are all very difficult, and the yield is very low.

Especially for high-silicon electrical steel, the higher the silicon content, the better the magnetic permeability, but with the increase of silicon content, the plasticity of the material is greatly reduced, the material becomes brittle, it is difficult to coil, it is difficult to uncoil, and the processing is more difficult

[0003] The technology that adopts the industrialization of material near-net forming manufacturing technology, such as the Castrip twin-roll thin strip production line in the United States, the twin-roll thin strip continuous casting technology jointly developed by Nippon Steel and Mitsubishi Heavy Industries, the Eurostrip process in Europe, and the Australian Strip continuous casting technology, etc., can only produce hot-rolled coils with a thickness of ≥0.75mm. If further processing is required, it is very difficult. The main manifestations are: difficulty in uncoiling, and the hard and brittle nature of high-silicon steel makes it impossible to uncoil, or even brittle. ; It is difficult to remove rust. A dense SiO2 and Fe2O3 film is formed on the surface of high silicon steel, which cannot be removed by conventional hydrochloric acid and sulfuric acid. Rust can only be cleaned by removing more than 80% of the oxide film; rolling is difficult, high-silicon electrical steel and difficult-to-process materials have high hardness, high brittleness, and poor plasticity, especially high-silicon electrical steel, which has almost zero plasticity at room temperature , cannot be cold-worked

If warm rolling is carried out, the rolled piece needs to be reheated, which affects the surface quality

[0004] The test equipment for near-final forming of difficult-to-machine alloy materials can only produce cast strips with a thickness ≥ 1.2mm, and further processing is more difficult