CN1772710A

CN1772710A - Production process of composite steel pipe with cermet lining

Info

Publication number: CN1772710A
Application number: CN 200510086802
Authority: CN
Inventors: 郭志猛; 高峰; 林涛
Original assignee: University of Science and Technology Beijing USTB
Current assignee: University of Science and Technology Beijing USTB
Priority date: 2005-11-07
Filing date: 2005-11-07
Publication date: 2006-05-17
Anticipated expiration: 2025-11-07
Also published as: CN1317425C

Abstract

The present invention provides the production process of composite steel pipe with cermet lining, and belongs to the field of steel surface coating technology. The production process includes mixing ferric oxide powder, aluminum powder, WO3 powder and graphite powder in the proportioning of reaction expression of Fe2O3+2(1+x)Al+xWO3+xC=(x+1)Al2O3+2Fe+xWC, where x is 0.5-3; reaction at high temperature to produce alumina, Fe in molten state and W and C dissolved in molten Fe; applying centrifugal force for alumina to distribute in the inner surface of steel pipe and Fe to combine with mother pipe metallurgically; lowering temperature for W and C to combine into WC separated from the molten Fe and distributed inside the metal layer and for the molten Fe to combine with mother pipe metallurgically; and eliminate surface oxide scale after cooling to obtain composite steel pipe with cermet lining. Different kinds of cermet lined steel pipe with adjustable components may be produced.

Description

Method for preparing metal ceramic lining composite steel pipe

Technical Field

The invention belongs to the technical field of steel surface coatings, and particularly provides a method for preparing a metal ceramic lining composite steel pipe. A method for coating a layer of metal ceramic on the inner surface of a steel pipe by using a self-propagating centrifugal method.

Background

The development of modern industry requires transportation of a large number of pipelines, and the pipelines are required to have certain wear resistance and corrosion resistance. The production method of the existing composite pipe is few, and mainly comprises a sleeving construction method, centrifugal casting, bimetal centrifugal casting, composite material welding and an SHS-centrifugal method. The SHS-centrifugal method has obvious advantages, and compared with the traditional rolling compounding, sintering compounding and explosion compounding, the SHS-centrifugal method has the characteristics of simple process, low energy consumption and the like. The SHS-centrifugal method can be used for manufacturing and producing ceramic-steel pipes, stainless steel-steel pipes and other composite pipes according to requirements. Self-propagating centrifugation has been applied to the technology of manufacturing ceramic lined steel pipes (e.g., japanese patent No. J58047550, chinese patent No. 90107244.4) which have excellent wear resistance but have poor corrosion resistance due to microcracks on the ceramic surface. In addition, the ceramic phase has high hardness and poor toughness, so that the problems of subsequent processing and pipeline connection exist.

Chinese patent 94104459.9 provides a method for producing corrosion-resistant and heat-resistant steel lining composite steel pipe by SHS-centrifugation method, mainly applied to corrosion resistance.

The cermet consists of a metallic binder phase and a ceramic phase. Common metal ceramics are made of refractory metal compounds (WC, TiC, Cr)₂C₃Etc.) as a matrix, and iron group metals (Co, Fe, Ni) as a binder phase. The metal ceramic not only keeps the characteristics of high strength, high hardness, wear resistance, high temperature resistance, oxidation resistance, good chemical stability and the like of the ceramic, but also has good metal toughness and plasticity and good processability.

Disclosure of Invention

The invention aims to provide a method for preparing a metal ceramic lining composite steel pipe, which is used for producing the lining metal ceramic lining composite steel pipe by an SHS-centrifugal method and enlarges the variety of the composite steel pipe.

The invention comprises the following contents: mixing iron oxide powder, aluminum powder, tungsten trioxide powder and graphite powder according to the following reaction formula, wherein x is adjustable according to the generation requirement, the range of x is 0.5-3,

the high temperature of the reaction makes the generated alumina, iron in a molten state, and tungsten and carbon are dissolved in the liquid iron. Under the action of centrifugal force, alumina is distributed on the inner surface of the steel pipe, iron with high specific gravity forms metallurgical bonding with the mother pipe, tungsten is bonded with carbon along with the reduction of temperature to generate tungsten carbide, a large amount of tungsten carbide is separated out in molten iron and distributed ina metal layer, and simultaneously the molten iron forms metallurgical bonding with the mother pipe. And after cooling, removing the oxide slag layer on the surface to obtain the metal ceramic lining steel pipe.

The key to the manufacture of the cermet lined steel pipe is the complete metallurgical bonding of the cermet layer to the parent pipe. The idea of the invention is to increase the combustion temperature and the high-temperature retention time and promote the metallurgical bonding of the metal ceramic layer and the steel pipe.

The present invention is described in detail as follows:

1、Fe₂O₃(or NiO) and Al powders are reaction materials for forming a binder phase, Fe₂O₃The (or NiO) and Al powder are mixed according to the reaction formula (or ) Proportioning.

2. Titanium dioxide powder was used instead of tungsten trioxide powder and mixed in the following reaction ratio: x is in the range of 0.1 to 0.27

3. The reaction materials are preheated to 100-400 ℃, and the reaction temperature and the high-temperature retention time can be increased.

4. Controlling the centrifugal acceleration of the raw materials to be 500-5000 m/s in the reaction process²。

The invention has the advantages that: the method can prepare the metal ceramic lining steel pipes of different systems, and has adjustable components, simple process and wide application.

Example 1: fe₂O₃320g of powder and 108gof Al powder were uniformly mixed to obtain a raw material powder for forming a binder phase. WO₃464g of powder, 54g of Al powder and 24g of graphite powder are uniformly mixed to form raw material powder for generating a hard ceramic phase. Will be at the topThe powders are mixed evenly, preheated to 100 ℃ and put into a mother pipe. The mother pipe is a carbon steel pipe with phi 74mm, 4mm of wall thickness and 200mm of length. The steel tube is clamped on a centrifuge, the centrifuge is started, the rotating speed is 1110 r/min (the centrifugal acceleration of the reaction raw material is 500 m/s)²) The tungsten wire is used to ignite the material, the combustion reaction is carried out under the centrifugal force, the huge heat is discharged, the aluminum oxide layer on the surface is removed after the cooling, and the metal ceramic lining steel pipe which takes iron as the binding phase and tungsten carbide as the hard phase is obtained.

Example 2: 333g of NiO powder and 81g of Al powder were uniformly mixed to prepare a raw material powder for forming a binder phase. 50g of TiC powder as a raw material powder of the hard ceramic phase. Mixing the above raw material powders uniformly, preheating at 100 deg.C and rotating speed of 3600 r/min (centrifugal acceleration of reaction raw material is 4975 m/s)²). In the same way as in example 1, a cermet lined steel pipe with TiC as the hard phase and Ni as the binder phase can be produced.

Example 3: fe₂O₃320g of powder and 108g of Al powder were uniformly mixed to obtain a raw material powder for forming a binder phase. TiO 2₂160g of Al powder, 144g of Al powder, and 24g of graphite powder were used as raw material powders for forming a hard ceramic phase. Mixing the above raw material powders uniformly, preheating at 350 deg.C, rotating at 2700 rpm (centrifugal acceleration of reaction raw material is 2934 m/s)²) Inthe same way as in example 1, a cermet lined steel pipe with TiC as the hard phase and Fe as the binder phase can be produced.

Claims

1. A method for preparing a metal ceramic lining composite steel pipe is characterized by comprising the following steps: mixing iron oxide powder, aluminum powder, tungsten trioxide powder and graphite powder Mixing the reaction formula in proportion, wherein x ranges from 0.5 to 3, the high temperature of the reaction enables the generated alumina, iron to be in a molten state, and tungsten and carbon are dissolved in liquid iron; alumina is distributed on the inner surface of the steel pipe under the action of centrifugal force, iron with large specific gravity forms metallurgical bonding with the mother pipe, tungsten is bonded with carbon along with the reduction of temperature to generate tungsten carbide, a large amount of tungsten carbide is separated out in molten iron and distributed in a metal layer, and simultaneously the molten iron forms metallurgical bonding with the mother pipe(ii) a And after cooling, removing the oxide slag layer on the surface to obtain the metal ceramic lining steel pipe.

2. The method of claim 1, wherein: controlling the centrifugal acceleration of the raw materials to be 500-5000 m/s in the reaction process²。

3. The method of claim 1, wherein: titanium dioxide powder is used instead of tungsten trioxide powder Mixing the reaction formula in proportion, wherein x ranges from 0.1 to 0.27.

4. The method of claim 1, wherein: the reaction materials are preheated to 100-400 ℃, and the reaction temperature and the high-temperature retention time can be increased.