CN101898246B - Method for preparing SHS ceramic liner metal tube from iron-based wastes - Google Patents
Method for preparing SHS ceramic liner metal tube from iron-based wastes Download PDFInfo
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- CN101898246B CN101898246B CN2010102302296A CN201010230229A CN101898246B CN 101898246 B CN101898246 B CN 101898246B CN 2010102302296 A CN2010102302296 A CN 2010102302296A CN 201010230229 A CN201010230229 A CN 201010230229A CN 101898246 B CN101898246 B CN 101898246B
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Abstract
The invention relates to a method for preparing an SHS ceramic liner metal tube from iron-based wastes and discloses a method for manufacturing a corrosion-resistant and wear-resistant ceramic liner metal tube. The technical scheme is that: the treated iron-based wastes and Al powder are proportioned, mixed and sintered through an SHS centrifugal thermit reaction; an iron alloy layer and a ceramic layer are formed on an inner wall of the metal tube under the action of centrifugal force; and the prepared metal tube has the sandwich structural characteristic, namely the ceramic layer 1, the iron alloy layer 2 and a metal tube substrate layer 3 are formed from the interior to the exterior in turn. The method for preparing the SHS ceramic liner metal tube solves the problem that the conventional ceramic liner metal tube has over-high manufacturing cost and ceramic surface quality defect, and improves the wear resistance and corrosion resistance of the tube. The prepared metal tube can be widely applied to conveying powder, slurry and tailings in metallurgy, mines, electric power, coal and other industries.
Description
Technical field
The present invention relates to the method that a kind of iron-based waste material is used for SHS ceramic liner metal tube material, belong to resource recycling and technical field of surface coating.
Background technology
Along with China's steel industry is fast-developing, iron-based waste material output sharply increases.The iron-based waste material comprises that roll dressing material, cold (heat) rolls iron scale etc.According to incompletely statistics, the iron-based waste material is annual about 2,000,000 tons.On the one hand the iron-based waste material has brought the serious environmental burden to iron and steel enterprise, and the iron-based waste material contains valuable metals resources such as a large amount of Fe and a certain amount of Cr, Ni, V, Mn on the other hand.Therefore, comprehensive utilization iron-based waste material not only can alleviate the environmental pressure of iron and steel enterprise, and helps resource reutilization, has important economy and environment protection significance.
Self propagating high temperature synthetic (Self-propagating High-temperature Synthesis, abbreviation SHS) is to utilize chemical reaction self heat release to prepare the new technology of material.Its outstanding feature is exactly the high energy exothermic reaction that makes full use of when forming compound between element, and except causing the necessary a small amount of external energy of synthetic reaction, entire reaction course mainly relies on the heat release of material self to keep.The combustion process influence of centrifugal force to thermit reaction studied by the Chemical Physics research institute of the academy of sciences of the former Soviet Union, and through the centrifugal force controlled combustion process, centrifugal force combines with the SHS process and produced the SHS-centrifugal process.Japanese Odawara in 1981 is repaiied and is adopted the aluminothermy centrifugal process to prepare the ceramic liner metal tube material, and prepares large scale lined ceramics composition metal tubing.Its principle is to utilize aluminium and iron oxide generation exothermic reaction; Relying on exothermic reaction can keep reaction carries out; Product iron and the instantaneous fusion of aluminium oxide simultaneously; Under action of centrifugal force, the aluminium oxide of light specific gravity is distributed in the metal pipe material inner surface, and heavy iron is distributed in the middle of metal pipe material and the ceramic layer and with metal pipe material and ceramic layer and combines.Al and Fe
2O
3(or Fe
3O
4) reaction equation following:
2Al+Fe
2O
3→2Fe+Al
2O
3
8Al+3Fe
3O
4→9Fe+4Al
2O
3
Chinese patent ZL90107244.3 discloses a kind of corrosion-proof wear ceramet tubing manufacturing technology, at Al+Fe
2O
3(or Fe
3O
4) add additive SiO simultaneously in the material
2With one or both alkali metal oxides (at Na
2O, K
2O, Li
2Select among the O) and one or both alkaline earth oxides RO (in MgO, CaO, BaO, ZnO, selecting); Material behind the mixing adds metal pipe material band material and is preheated to 100 ℃～300 ℃, lights the back reaction-sintered that under action of centrifugal force, carries out, and forms the about 2 millimeters no permeability ceramic of compact coating of thickness at the metal pipe material inwall.Chinese patent 01139227.4 discloses a kind of manufacturing approach of ceramic liner metal tube material, with acid sludge material (iron ore beneficiation generation) and Al, SiO
2The oven dry mixing is lighted the back and under action of centrifugal force, is carried out reaction-sintered, forms ceramic of compact coating at the metal pipe material inwall.
For low-cost high-efficiency utilizes the iron-based waste material, make full use of wherein Fe, Cr, Ni, V, Mn, Al
2O
3And SiO
2Material utilizes thermit reaction to carry out the metal pipe material of the centrifugal preparation of SHS " sandwich " structure.Do not see and relevant bibliographical information of the present invention
Summary of the invention
The objective of the invention is to propose a kind of method, realize low-cost high-efficiency utilization the iron-based waste material with preparing SHS ceramic liner metal tube from iron-based wastes.
Because of the iron-based waste material contains metallic elements such as a large amount of Fe and a spot of Cr, Ni, V, Mn, exist with metal simple-substance and metal oxide form.Metal oxide and Al powder all can carry out the SHS thermit reaction, under action of centrifugal force, form iron alloy layer, Al at metal pipe material
2O
3Or Al
2O
3+ SiO
2Ceramic layer, improved metal pipe material anti-wear performance and corrosion resistance.Because of containing certain Al in the iron-based waste material
2O
3And SiO
2, not only improve the flowability of powder, and increase the thickness and the surface quality of metal pipe material lined ceramics.
A kind of method of the present invention with preparing SHS ceramic liner metal tube from iron-based wastes; Be to be raw material with iron-based waste material and Al powder; With treated iron-based waste material and proportioning, the mixing charging in proportion of Al powder; Then material is carried out the SHS reaction-sintered in the centrifugal back of lighting on the centrifuge under action of centrifugal force, form iron alloy layer and ceramic of compact coating at the metal pipe material inwall.Specifically may further comprise the steps:
1) the iron-based waste material is carried out 200 ℃～500 ℃ baking hydrofuge, removal of impurities down;
2) carry out 80 orders～300 mesh sieve branches, close batch;
3) the powder composition detection after closing batch;
4) carrying out proportioning with the Al powder mixes;
5) mixed raw material is added the metal pipe material uniform distribution;
6) start tuber, carry out the SHS-centrifugal process and prepare ceramic plated layer.
In the said step 4), Al powder and iron-based grinding waste material mass ratio are 1: 10～4: 1.
Said process removes Fe
2O
3Outside reacting with the Al powder, one or more of following thermit reaction also take place.
2Al+Cr
2O
3→2Cr+Al
2O
3
2Al+3NiO→3Ni+Al
2O
3
10Al+3V
2O
5→6V+5Al
2O
3
4Al+3MnO
2→3Mn+2Al
2O
3
What participate in thermit reaction is the iron-based waste material, and said iron-based waste material is the accessory substance of Ferrous Metallurgy, comprises that roll dressing material, cold (heat) rolls iron scale, and the composition of said iron-based waste material is Fe and oxide thereof, Al
2O
3, SiO
2, and any one or more metallic element among the Cr that exists with metal simple-substance and metal oxide form, Ni, V, Mn; Said Al
2O
3, SiO
2Can reduce the fusing point of SHS reaction system, improve flowability, increase the ceramic-lined thickness of metal pipe material, improve the ceramic layer surface quality
In the thermit reaction process; The metal more than 2 kinds or 2 kinds of Fe, Cr, Ni, V, Mn can form binary or polynary iron alloy layer; Under action of centrifugal force, be uniformly distributed between tubing matrix and the ceramic layer; Form " sandwich " structure, be followed successively by ceramic layer (1), iron alloy layer (2) and metal pipe material base layer (3) from inside to outside.
Advantage of the present invention is:
1. replace Fe with cheap iron-based waste material
2O
3Or other ceramic powders, greatly reducing cost of material, raw material sources are extensive;
2.Cr, oxide and Al powder SHS reactions such as Ni, V, Mn, at inner binary or the multicomponent alloy that forms Fe, Cr, Ni, V, Mn of ceramic layer, this alloy has strengthened intensity, hardness, the wearability of tubing.
3. the iron-based waste material also contains a certain amount of Al
2O
3And SiO
2, can absorb heat in the SHS process and be melted, it is too high to suppress temperature, can prevent the metal pipe material distortion;
4.SiO
2Help reducing Al
2O
3The primary phase crystallization temperature increases ceramic melt life period, promotes gas phase to overflow, thereby improves the quality of ceramic layer.
Figure of description
Fig. 1 is a SHS ceramic liner metal tube material radial section, and 1 is ceramic layer, and 2 is iron alloy layer, and 3 is the metal pipe material base layer.
Fig. 2 is the ability spectrogram of iron-based waste material.
Fig. 3 is the Al of iron-based waste material
2O
3And SiO
2X-ray diffractogram.
The specific embodiment
Embodiment 1:
To contain Cr, Ni, V, Mn metallic element (see figure 2), Al
2O
3And SiO
2Iron-based waste material (see figure 3) carry out 200 ℃ of bakings, remove steam and impurity, screening obtains-80 order powder.Mix with reducing agent Al powder, its mass ratio is the Al powder: the iron-based waste material is 1: 10.Compound is evenly packed in the steel pipe, is fixed on the tuber.Start centrifuge, when rotating speed reaches 800 rev/mins, light compound with tungsten filament the centrifugal reaction-sintered of SHS takes place.Under centrifugal action, form the steel pipe of " sandwich " structure, be followed successively by ceramic layer 1, iron alloy layer 2 and steel pipe base layer 3 from inside to outside.The crushing strength of steel pipe is 326MPa, and hardness is 1280kgf/mm
2Inner lining of steel pipe is respectively at 20%H
2SO
4, accelerated corrosion in 20%HCl and the chloroazotic acid, its weightlessness is respectively 0.08g/m
2D, 0.08g/m
2D and 0.12g/m
2D.
Embodiment 2:
To contain metallic element (see figure 2), Al such as Cr, Ni, V, Mn
2O
3And SiO
2Iron-based waste material (see figure 3) carry out 300 ℃ of bakings, remove steam and impurity, screening obtains-120 order powder.Mix with reducing agent Al powder, its mass ratio is the Al powder: the iron-based waste material is 1: 5.Compound is evenly packed in the steel pipe, is fixed on the tuber.Start centrifuge, when rotating speed reaches 1200 rev/mins, light compound with tungsten filament the centrifugal reaction-sintered of SHS takes place.Under centrifugal action, form the steel pipe of " sandwich " structure, be followed successively by ceramic layer 1, iron alloy layer 2 and steel pipe base layer 3 from inside to outside.The crushing strength of steel pipe is 315MPa, and hardness is 1380kgf/mm
2Inner lining of steel pipe is respectively at 20%H
2SO
4, accelerated corrosion in 20%HCl and the chloroazotic acid, its weightlessness is respectively 0.06g/m
2D, 0.04g/m
2D and 0.10g/m
2D.
Embodiment 3:
To contain metallic element (see figure 2), Al such as Cr, Ni, V, Mn
2O
3And SiO
2Iron-based waste material (see figure 3) carry out 400 ℃ of bakings, remove steam and impurity, screening obtains-180 order powder.Mix with reducing agent Al powder, its mass ratio is the Al powder: the iron-based waste material is 1: 1.Compound is evenly packed in the steel pipe, is fixed on the tuber.Start centrifuge, when rotating speed reaches 1400 rev/mins, light compound with tungsten filament the centrifugal reaction-sintered of SHS takes place.Under centrifugal action, form the steel pipe of " sandwich " structure, be followed successively by ceramic layer 1, iron alloy layer 2 and steel pipe base layer 3 from inside to outside.The crushing strength of steel pipe is 308MPa, and hardness is 1420kgf/mm
2Inner lining of steel pipe is respectively at 20%H
2SO
4, accelerated corrosion in 20%HCl and the chloroazotic acid, its weightlessness is respectively 0.05g/m
2D, 0.04g/m
2D and 0.09g/m
2D.
Embodiment 4:
To contain metallic element (see figure 2), Al such as Cr, Ni, V, Mn
2O
3And SiO
2Iron-based waste material (see figure 3) carry out 500 ℃ of bakings, remove steam and impurity, screening obtains-240 order powder.Mix with reducing agent Al powder, its mass ratio is the Al powder: the iron-based waste material is 2: 1.Compound is evenly packed in the steel pipe, is fixed on the tuber.Start centrifuge, when rotating speed reaches 1600 rev/mins, light compound with tungsten filament the centrifugal reaction-sintered of SHS takes place.Under centrifugal action, form the steel pipe of " sandwich " structure, be followed successively by ceramic layer 1, iron alloy layer 2 and steel pipe base layer 3 from inside to outside.The crushing strength of steel pipe is 300MPa, and hardness is 1510kgf/mm
2Inner lining of steel pipe is respectively at 20%H
2SO
4, accelerated corrosion in 20%HCl and the chloroazotic acid, its weightlessness is respectively 0.04g/m
2D, 0.03g/m
2D and 0.07g/m
2D.
Embodiment 5:
To contain metallic element (see figure 2), Al such as Cr, Ni, V, Mn
2O
3And SiO
2Iron-based waste material (see figure 3) carry out 300 ℃ of bakings, remove steam and impurity, screening obtains-300 order powder.Mix with reducing agent Al powder, its mass ratio is the Al powder: the iron-based waste material is 4: 1.Compound is evenly packed in the steel pipe, is fixed on the tuber.Start centrifuge, when rotating speed reaches 1300 rev/mins, light compound with tungsten filament the centrifugal reaction-sintered of SHS takes place.Under centrifugal action, form the steel pipe of " sandwich " structure, be followed successively by ceramic layer 1, iron alloy layer 2 and steel pipe base layer 3 from inside to outside.The crushing strength of steel pipe is 290MPa, and hardness is 1600kgf/mm
2Inner lining of steel pipe is respectively at 20%H
2SO
4, accelerated corrosion in 20%HCl and the chloroazotic acid, its weightlessness is respectively 0.03g/m
2D, 0.02g/m
2D and 0.05g/m
2D.
Embodiment 6:
To contain metallic element (see figure 2), Al such as Cr, Ni, V, Mn
2O
3And SiO
2Iron-based waste material (see figure 3) carry out 400 ℃ of bakings, remove steam and impurity, screening obtains-180 order powder.Mix with reducing agent Al powder, its mass ratio is the Al powder: the iron-based waste material is 1: 1.Compound is evenly packed in the copper pipe, is fixed on the tuber.Start centrifuge, when rotating speed reaches 1400 rev/mins, light compound with tungsten filament the centrifugal reaction-sintered of SHS takes place.Under centrifugal action, form the copper pipe of " sandwich " structure, be followed successively by ceramic layer 1, iron alloy layer 2 and steel pipe base layer 3 from inside to outside.The crushing strength of copper pipe is 276MPa, and hardness is 1390kgf/mm
2Inner lining of steel pipe is respectively at 20%H
2SO
4, accelerated corrosion in 20%HCl and the chloroazotic acid, its weightlessness is respectively 0.04g/m
2D, 0.03g/m
2D and 0.02g/m
2D.
Embodiment 7:
To contain metallic element (see figure 2), Al such as Cr, Ni, V, Mn
2O
3And SiO
2Iron-based waste material (see figure 3) carry out 400 ℃ of bakings, remove steam and impurity, screening obtains-200 order powder.Mix with reducing agent Al powder, its mass ratio is the Al powder: the iron-based waste material is 2: 1.Compound is evenly packed in the stainless pipe, is fixed on the tuber.Start centrifuge, when rotating speed reaches 1100 rev/mins, light compound with tungsten filament the centrifugal reaction-sintered of SHS takes place.Under centrifugal action, form the steel pipe of " sandwich " structure, be followed successively by ceramic layer 1, iron alloy layer 2 and steel pipe base layer 3 from inside to outside.The crushing strength of stainless steel tube is 312MPa, and hardness is 1360kgf/mm
2Inner lining of steel pipe is respectively at 20%H
2SO
4, accelerated corrosion in 20%HCl and the chloroazotic acid, its weightlessness is respectively 0.03g/m
2D, 0.02g/m
2D and 0.01g/m
2D.
Claims (1)
1. method with preparing SHS ceramic liner metal tube from iron-based wastes; It is characterized in that: with iron-based waste material and Al powder is raw material; With treated iron-based waste material and proportioning, the mixing charging in proportion of Al powder; Then material is carried out the SHS reaction-sintered in the centrifugal back of lighting on the centrifuge under action of centrifugal force, form iron alloy layer and ceramic of compact coating at the metal pipe material inwall; May further comprise the steps:
1) the iron-based waste material is carried out 200 ℃～500 ℃ baking hydrofuge, removal of impurities down; Said iron-based waste material is the accessory substance of Ferrous Metallurgy, comprises roll dressing material, cold rolling iron scale, hot rolling iron scale, and the composition of said iron-based waste material is Fe and oxide thereof, Al
2O
3, SiO
2, and among the Cr that exists with metal simple-substance and metal oxide form, Ni, V, Mn any one or more; Said Al
2O
3, SiO
2Can reduce the fusing point of SHS reaction system, improve flowability, increase the ceramic-lined thickness of metal pipe material, improve ceramic layer (1) surface quality;
2) carry out 80 orders～300 mesh sieve branches, close batch;
3) the powder composition detection after closing batch;
4) carry out proportioning with the Al powder and mix, said Al powder and iron-based grinding waste material mass ratio are 1: 10～4: 1;
5) raw material that mixes is added the metal pipe material uniform distribution;
6) start tuber, carry out the SHS-centrifugal process and prepare the ceramic liner metal tube material, described ceramic liner metal tube material has " sandwich " architectural feature, is followed successively by ceramic layer (1), iron alloy layer (2) and metal pipe material base layer (3) from inside to outside.
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| CN102161595A (en) * | 2011-02-14 | 2011-08-24 | 江阴东大新材料研究院 | Static-centrifugal composite method for preparing ceramic lining coating of steel tube |
| CN102699331A (en) * | 2012-05-11 | 2012-10-03 | 新兴铸管股份有限公司 | Method for making wear-resistant coating on inner surface of nodular cast iron pipe |
| CN102899663A (en) * | 2012-10-30 | 2013-01-30 | 江阴东大新材料研究院 | Method of preparing metal coating on inner surface of steel pipe through SHS (Self-propagation High-temperature Synthesis) centrifugal method |
| CN103062574B (en) * | 2012-12-26 | 2015-08-12 | 杨永利 | Cermet lining line pipe and preparation method |
| CN104046978A (en) * | 2014-05-29 | 2014-09-17 | 仲玥 | Method for preparing coating layer of steel pipe inner surface by SHS ultrasonic emulsification centrifugal method |
| CN104475734B (en) * | 2015-01-23 | 2016-07-13 | 武汉大学 | A kind of manufacture method of ceramic-lined aluminum pipe |
| CN105333238B (en) * | 2015-08-26 | 2024-06-04 | 杨永利 | Metal ceramic composite oil pipe manufactured by remanufacturing waste oil pipe and remanufacturing process thereof |
| WO2018074433A1 (en) * | 2016-10-18 | 2018-04-26 | 新日鐵住金株式会社 | Collapse strength predicting method |
| CN108746639A (en) * | 2018-05-30 | 2018-11-06 | 安徽工程大学 | A kind of the SHS metallurgical powder and its application method multiple for H13 steel pipe die repairs |
| CN108642489A (en) * | 2018-05-30 | 2018-10-12 | 安徽工程大学 | A kind of the SHS metallurgical powder and its application method multiple for 21CrMo10 steel pipe die repairs |
| CN108642490A (en) * | 2018-05-30 | 2018-10-12 | 安徽工程大学 | A kind of SHS metallurgical powders and its application method for 15CrMoQ pipe die reparations |
| CN111715883B (en) * | 2019-03-21 | 2021-03-16 | 南京科亚化工成套装备有限公司 | Preparation method of extruder barrel |
| CN110039056B (en) * | 2019-05-27 | 2020-01-03 | 西南交通大学 | Preparation method of iron-based composite material |
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