Preparation method of double-layer or multi-layer metal composite pipe blank

Abstract

The invention provides a preparation method of a double-layer or multi-layer metal composite pipe blank. The preparation method comprises the steps that the upper ends of a pretreated inner metal pipe and a pretreated outer metal pipe and the lower ends of the pretreated inner metal pipe and the pretreated outer metal pipe are fixed to circular seams of an upper sealing flange and a lower sealing flange respectively, and a casting cavity is formed between the inner metal pipe and the outer metal pipe; a casting device and an air inlet and exhaust device are arranged through the upper sealing flange to carry out exhausting and preheating on the casting cavity; metal melt is poured into the casting cavity to form a composite pipe blank; and the composite pipe blank is cooled and finished, and the excellent composite pipe blank is obtained. According to the method, the double-layer or multi-layer metal composite pipe blank which cannot be produced through existing methods and is provided with a solid-liquid phase metallurgical bonding interface can be prepared, and the technological method has the beneficial effects of being simple in technology, low in manufacturing cost, good in interface bonding quality of the composite pipe blank, high in yield, capable of being used for preparing various double-layer or multi-layer metal composite pipe blanks and the like.

Description

technical field [0001] The invention relates to a method for preparing metal tube blanks, which belongs to the field of layered metal composite materials, and is especially suitable for preparing double-layer or multi-layer metal composite tube blanks. Background technique [0002] Metal composite pipe is a pipe made of two or more metal pipes of different materials through mechanical or metallurgical methods. It makes full use of the advantages of two or more metals, saves rare and precious metals, and is cost-effective. Therefore, in recent years, composite double-layer or multi-layer metal pipes have become more and more popular. [0003] At present, there are many methods for preparing double-layer or multi-layer metal composite tube blanks. The most commonly used method is the nesting method, that is, the inner and outer surfaces of the two tube blanks to be compounded are cleaned first, and then one of the tube blanks is inserted into the Inside the other tube blank, ...

AI Technical Summary

Problems solved by technology

Although the nesting billet making process is simple, there is a large gap between the inner and outer tube billets, and subsequent large-deformation pressure processing is required to obtain high-quality composite pipes; although the centrifugal casting billet making process can obtain higher interface bonding strength , but it is easy to form a mixed melting zone of the two metals at the interface, thus forming an interface compound, resulting in poor toughness of the interface area; the brazing connection method adds a transition layer at the interface to improve the interface quality, but due to the interface The addition of brazing material increases the production cost; the solid bimetal billet for die casting needs to be further perforated to obtain the hollow capillary tube, and the process is relatively complicated; after the tube blank is used for lost foam casting, the outer layer is casted with carbon steel tube billet by sand casting The method increases the cost of lost foam and sand mold production, and the process cost increases

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