Preparation method of nickel-based duplex metal composite used for fluorine chemical production equipment

Abstract

The invention discloses a preparation method of a nickel-based duplex metal composite used for fluorine chemical production equipment. The preparation method of the nickel-based duplex metal composite used for the fluorine chemical production equipment comprises the following steps that (1) base materials and composite materials are selected according to working condition requirements; (2) smelting and refining are conducted, specifically, the base materials and the composite materials are melted through a medium-frequency induction furnace, and then refining is conducted through a refining surface for composition adjustment; (3) centrifugal pressure casting is conducted on a composite tube blank, specifically, a refined metal solution is subjected to centrifugal pressure casting through a centrifugal combined steel casting machined, and the composite tube blank is obtained; (4) external descaling is conducted, specifically, inner boring and external descaling are conducted on the poured composite tube blank, and defected portions are removed; (5) hot extrusion and cogging are conducted, the composite tube blank is subjected to initial deformation, and thermal treatment is conducted; and (6) a finished product is obtained through cold rolling. According to the material prepared through the preparation method, a base layer is in complete metallurgical bonding with a composite layer (the bonding force of a composite surface is high), the structure is compact, and the strength is high.

Description

technical field [0001] The invention relates to a preparation method of a nickel-based bimetallic composite material, in particular to a preparation method of a nickel-based bimetallic composite material used in fluorine chemical production equipment. Background technique [0002] At present, there are mainly two ways to produce composite seamless steel pipes at home and abroad: 1) Internal expansion type, that is: seamless steel pipes of two materials are used to wear each other (for example, the outer pipe is made of ordinary ordinary carbon steel seamless steel pipe, and the inner pipe is made of one Thin-walled stainless steel pipe as the inner metal pipe), high pressure is applied to the inner pipe, so that the inner steel pipe undergoes plastic deformation and the outer steel pipe only produces elastic deformation, so that the inner pipe and the outer pipe are tightly combined to form a bimetal composite seamless Steel pipe; 2) Outer diameter reduction type, that is, s...

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Problems solved by technology

[0003] The disadvantages of the above two types of double-layer metal composite seamless steel pipes are: the production cost is high, the inner and outer pipes must use ready-made hot-rolled or cold-drawn seamless steel pipes, and the subsequent internal expansion or diameter reduction process makes it The manufacturing cost has risen sharply; the above two types of seamless steel pipes are not bimetallic composites, because there is no metallurgical fusion between the two layers of metal, and basically belong to the category of mechanical fitting. Under the condition of axial force, the inner and outer layers It is difficult for metal to transmit and balance external forces; in the application field that requires heat transfer, due to the gap between the inner and outer metal layers, the thermal resistance will increase greatly; And there is no restriction of the fusion interface. For long-term pipelines, the difference in size and stress caused by the expansion of the inner and outer metal layers will be concentrated at the connection end, resulting in damage to the connection end of the long-line pipeline or the inner tube protruding and falling off.

[0004] At the same time, the above two types of double-layer metal composite seamless steel pipes are likely to cause welding failure during layered welding because there is basically no composition transition zone between the inner and outer layer metal, or there is a bonding gap.

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