CN101254542A - Iron-based brassiness powder metallurgy material and preparation - Google Patents
Iron-based brassiness powder metallurgy material and preparation Download PDFInfo
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- CN101254542A CN101254542A CNA2008100695749A CN200810069574A CN101254542A CN 101254542 A CN101254542 A CN 101254542A CN A2008100695749 A CNA2008100695749 A CN A2008100695749A CN 200810069574 A CN200810069574 A CN 200810069574A CN 101254542 A CN101254542 A CN 101254542A
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Abstract
The invention requests to protect an iron-based brass powdery metallurgical material and relates to a preparation method thereof. The preparation method comprises the following steps: uniformly coating a copper and zinc composite layer on the surface of iron particles by liquid-phase precipitation; dewatering and oven-drying to diffuse copper and zinc metals to the surface of iron-based particles to obtain a powdery metallurgical material. The metallurgical material consists of, calculated by iron powder 100 weight parts, copper 3 to 25% of the weight of iron powder, zinc 3 to 40% of the weight of copper, and iron powder in balance. The iron-based brass powdery metallurgical material and the preparation method thereof can better solve the problems of segregation of alloy components, incomplete coating of copper layer and iron base powder, insufficient strength, easy falling off, etc. The brass alloy is superior to pure copper in oxidation resistance, so that antioxidant treatment is obviated to lower the production cost. The brass alloy is an ideal material as the substitute of copper powder, copper-coated iron powder and bronze powder desired for sintering metal oil content bearing and manufacturing mechanical parts, hard alloy and diamond products.
Description
Technical field
The invention belongs to powder metallurgical technology, be specifically related to a kind of iron-based brassiness powder metallurgy material and manufacture method, it is an important material manufacturing technology, be sintering metal oiliness bearing and manufacturing machine constitutional detail and carbide alloy in the powder metallurgy industry, required a kind of special of diamond composition substitutes the manufacture method of the iron-based brassiness powder of copper powder.
Background technology
In the modern mechanical process industry, bearing material is the important frame for movement material of a class, and all rotational parts in machine and the mechanism all need to support with bearing, bearing shell or axle sleeve.Because the moving rotary speed of modern machines and mechanism and load are sharply increasing, and because the development of aerospace, nuclear energy and cryogenic technique, in the existing bearing material, according to service life and the possibility of under different conditions, working, the application of sintered-metal bearing material all holds pride of place, and has now become the indispensable class fundamental parts of development such as automobile, household electrical appliances, stereo set, office equipment, food machinery, agricultural machinery, microminiature motor, precision optical machinery.Show according to interrelated data, be about 9000 tons, on average in each Japanese machine at one's side 10 oiliness bearings are housed in the output of Japanese sintering metal oiliness bearing in 2006, and 5 of China's less thaies.These hypomegetic metal oil bearings can't be made with the processing method of traditional metal balls bearing, but adopt powder metallurgy process, mix mutually with copper powder or use copper-clad iron powder, bronze powder manufacturing with iron powder.When mixing mutually with copper powder,, be easy to generate component segregation, cause the sintered bearing metallographic structure inhomogeneous, defective such as intensity is inhomogeneous, and running-in ability is poor, and coefficient of friction is big, and noise is big because the granularity and the apparent density of iron powder and copper powder differ bigger with iron powder; When making with the copper-clad iron powder, because copper and iron cladding are not exclusively, the iron powder that has is not multiple by copper-clad, the cladding insufficient strength of copper layer and ferrous powder granules in addition, be easy to generate the copper pull-up and fall, when making metal oil bearing, be prone to stain, piebald, intensity difference, insufficient formability, the place of revealing iron is bigger to the turning cylinder wearing and tearing, defectives such as service life is short are the powder of thick level; And make oiliness bearing with bronze powder, and because soaring of copper price causes production cost to increase severely, product price is too high, market is difficult to be accepted.Interrelated data shows that the PR of China's iron-based powder metallurgy parts in 2006 increased by 19% in 2005, and copper base part descends 29%.This be since nonferrous metal price such as copper powder increase too high due to.On the other hand,, compared with 2005 in 2006 from the output of oiliness bearing, the increase of production 39% of iron-based oiliness bearing, and copper base oil containing bearing output has lowered 31%, because the copper powder rise in price, the copper base oil containing bearing is being used the iron-based oiliness bearing in a large number instead.
Show that according to the powder metallurgy interrelated data China's electric tool after-market in 2006 increased by 29.25% auto parts market growth 28.3%, motorcycle parts market growth 12.3% than 2005.This shows that under the extraordinary speed development of China's automobile industry drove, powdered metal parts production had entered the auto parts developing stage.Auto output was about 1,200 ten thousand in Japanese 2006, use 97690 tons of powdered metal parts altogether, sintering metal oiliness bearing output is 7964 tons, and being used for vehicles such as automobile is 4371 tons, average each automobile weight of powdered metal parts, Japanese 8.7kg, U.S. 19.8kg, China 3.97kg.In 727.97 ten thousand automobiles of China's production in 2006, on average each uses powdered metal parts weight to have only 3.97kg.And these automobiles all use iron and bronze material.Because the iron corrosion resistance is poor, easily to get rusty, service life is short; Bronze sill corrosion resistance is good, but intensity difference, the production cost height.
Summary of the invention
The present invention proposes a kind of iron-based brassiness powder metallurgy material and preparation method thereof, be required a kind of special of sintering metal oiliness bearing and manufacturing machine part and carbide alloy in the powder metallurgy industry, diamond composition, substitute the ideal material of copper powder, copper-clad iron powder, bronze powder.
Iron-based brassiness powder of the present invention is to adopt liquid-phase precipitation method, coat layer of copper, zinc composite bed equably on the ferrous powder granules surface, then through dehydration, oven dry heat treatment, make copper, two kinds of metal diffusions of zinc be fused to the iron-based grains surface, obtain a kind of yellow or golden yellow, red brass clad, through broken, sieving obtains iron-based brassiness powder.Comprise iron, copper and zinc in its raw material, their content is as follows, in 100 parts of the weight of iron powder, copper is the 3-25% of iron powder weight, zinc is the 3-40% of weight of copper, can change the color (can be yellow, golden yellow, dark yellow and redness, kermesinus) of material by the percentage by weight between allotment copper, the zinc.
Above-mentioned iron-based brass powder preparation methods is:
1) preparation of liquid-phase precipitation solution:
Mantoquita, 0.5-40kg zinc sulfate with iron powder weight 15-80kg with after the dissolving of 100kg clean tap water, filters stand-by respectively respectively;
2) preparation of brightener:
300-500mL formaldehyde and the dissolving of 10-50g thiocarbamide is stand-by;
3) copper, zinc co-precipitation are on the ferrous powder granules surface
(1) with in the copper-bath of step 1), the solution of zinc sulfate suction liquid-phase precipitation device, mixes while stirring, transfer mixed liquor volume to 400-450L, continue to stir with clean tap water;
(2) add activator by above-mentioned mixed solution 5-9mL/L, press 0.5-2g/L and add toner, and press 0.01-0.025mL/L adding brightener;
(3) continue to stir and add the 100kg reduced iron powder, be deposited in the ferrous powder granules surface until copper, two kinds of metals of zinc, color gray or redness allow the solution natural subsidence;
4) after solution sinks clearly, inhale and remove supernatant, put into centrifuge dewatering, remove most of moisture content, take out and carry out the drying processing;
5) with dry grey or kermesinus powder, send in the heat-treatment furnace of reduction protection atmosphere, through 430-700 ℃ of heat treatment, two kinds of metals diffusions of copper, zinc are merged on iron matrix powder particles surface, obtain having yellow, golden yellow or the red iron-based brassiness powder brass coating layer, that slightly lump;
6) iron-based brassiness powder that will slightly lump is through smashing to pieces, after the fragmentation, by the user demand of material granule degree being sieved;
7) iron-based brassiness powder through sieving again by the requirement of user to product apparent density, flowability etc., mixes with mixing the powder machine, after inspection by sampling is qualified, and packing, warehouse-in.
In the said method, copper salt solution can adopt copper chloride, cupric pyrophosphate, copper sulphate etc.In these mantoquitas, copper sulphate has that composition is simple, and production cost is low, is easy to control, and stable, market is easily purchased, so, make iron-based brassiness powder and use copper sulphate, preferably cupric sulfate pentahydrate.Copper sulphate is main salt, and its copper ion that dissociates out in the aqueous solution is the source of copper.
Zinc sulfate is the source of zinc ion in the solution.
Activator is a sulfuric acid.In solution, can reduce the resistance of solution, make the standard electrode potential difference of various metals in the solution dwindle or equate, impel each metal ion species to precipitate quickly and can prevent that also the copper sulphate hydrolysis from generating cuprous oxide or other precipitation of salts, the use amount of sulfuric acid can change in a big way.
The primary condition of liquid phase coprecipitation
Metal in a, the alloy has at least a kind of metal to separate out from the aqueous solution of its salt, the metal that has as: tungsten, molybdenum etc. can not be from the aqueous solution of its salt precipitation separately, but can with other metal as: iron, cobalt, nickel etc. are realized co-precipitation simultaneously from the aqueous solution.So co-precipitation might not require each component metals to precipitate from the aqueous solution separately to separate out.
The deposition potential of b, two kinds of metals is very approaching or equal.Because, in coprecipitation process, the preferential precipitation always of the metal of current potential calibration, even can get rid of the negative precipitated metal of current potential fully and come out.Therefore, for the metal that makes electrode potential differ far away is separated out simultaneously, can separate out the overpotential realization by changing ionic activity or different metal ion.
The standard electrode potential of copper is+0.34V, the standard electrode potential of zinc is-0.76V, the standard electrode potential of iron is-0.44V, this shows, copper, zinc, the standard electrode potential of iron differs bigger, in solution,, the resistance of solution is reduced owing to added activator sulfuric acid, make copper like this, zinc, the deposition potential of iron is very approaching or equal, copper, zinc is deposited in the surface of iron simultaneously, obtains copper, zinc, iron composite powder is through heat treatment, zinc is at high temperature melted be diffused into the copper the inside, form alloy with copper, thereby obtain yellow, golden yellow or red layer of brass is coated on the ferrous powder granules surface, makes the iron-based brassiness powder material.
This iron-based brassiness powder can be used on alternative copper powder, the copper-clad iron powder of making sintering metal oiliness bearing, carbide alloy, diamond composition, additive and making various machine components, and part substitutes bronze powder and ideal materials lead-free environmental protection and energy saving.
Advantage of the present invention is as follows:
Advantage of the present invention is as follows: this iron-based brass powder is because after adopting liquid-phase precipitation, through one to twice heat treatment, zinc is dissolved in the copper, forms ormolu, and (brass) tightly merges and is diffused in iron matrix powder particles surface, the segregation that has solved alloying component well; The cladding of copper layer and matrix iron powder is incomplete, insufficient strength, and problem such as easily come off; And the non-oxidizability of brass alloys is better than elemental copper, and the iron-based brass powder has reduced production cost without anti-oxidant treatment.Therefore adopt the iron-based brass powder to make oiliness bearing and compare, have the following advantages with the oiliness bearing of iron, copper mixed powder, the manufacturing of copper-clad iron powder:
1, good moldability, the intensity height, corrosion-resistant, good in oxidation resistance;
2, wear-resisting, coefficient of friction is good, and noise is low;
3, can bear high load capacity, high rotating speed has good oscillating load ability, and than copper-clad iron powder, the oiliness bearing of iron copper mixed powder manufacturing prolongs 70-100% service life under equal service condition;
4, compare with bronze material:
(1) the iron-based brassiness powder material is not leaded, meets the ROHS of European Union command request;
(2) do not need too many expensive nonferrous materials, manufacturing cost is very low, about the 1/15-1/20 for bronze material, can save metallic copper 60-70%;
(3) alternative copper base, copper-clad iron powder, part substitutes the bronze powder material.
The specific embodiment
Embodiment 1,
1, the preparation of liquid-phase precipitation liquid
With 15kg cupric sulfate pentahydrate and the dissolving of 100kg clean tap water,, filter stand-by respectively with 3kg zinc sulfate and the dissolving of 100kg clean tap water.
2, the preparation of brightener
Dissolve stand-by with the 10g thiocarbamide 300mL formaldehyde.
3, copper, zinc co-precipitation are on the ferrous powder granules surface
(1) with in the above-mentioned liquid-phase precipitation liquid suction settling vessel, after mixing while stirring, transfer mixed liquor volume to be about 400L with clean tap water, continue to stir.
(2) add 5mL/L activator sulfuric acid, 0.5g/L metal zinc and 0.01mL/L brightener by above-mentioned liquor capacity.
(3) continue to stir 15 minutes, slowly add the 100kg reduced iron powder equably, stop after 15 minutes stirring, (at this moment a lot of minute bubbles have appearred in solution surface, copper, two kinds of metals of zinc have been deposited in the ferrous powder granules surface, color gray or redness), allow the solution natural subsidence.
4, after solution sinks clearly, remove most of supernatant with the suction of siphon method, put into centrifuge dewatering operation 10-20 minute, remove most of moisture content, taking-up is sub-packed in the stainless steel disc, sends into baking oven through 70-200 ℃, 20-40 minute drying processing.
5, with dry grey or kermesinus powder; the burning of packing into boat is sent in the heat-treatment furnace of reduction protection atmosphere; through 430-700 ℃, 20-70 minute heat treatment; copper, two kinds of metal diffusions of zinc are merged on iron matrix powder particles surface; (at this moment zinc and copper have formed alloy); obtain yellow, golden yellow or red brass coating layer, the iron-based brassiness powder that is slightly lumpd.
6, the iron-based brassiness powder of slight caking is through smashing to pieces, after the fragmentation, by the user demand of material granule degree being sieved.
7, the iron-based brassiness powder through sieving is packed into and is mixed in the powder machine, and to the product apparent density, the requirement of flowability etc. under the condition of mixing 18-25 rev/min in powder machine, mixed 3-19 minute, pressed control gauge and then carried out inspection by sampling by the user.
8, inspection by sampling qualified after, press the 25kg/ bag, the packing of checking the weight becomes product warehousing.
Embodiment 2
1, the preparation of liquid-phase precipitation liquid
Respectively with the 80kg copper chloride, 40kg zinc sulfate is with the dissolving of 150kg clean tap water and filter stand-by.
2, the preparation of brightener
500mL formaldehyde and the dissolving of 50g thiocarbamide is stand-by.
3, copper, zinc co-precipitation are on the ferrous powder granules surface.
(1) with in the copper chloride solution of step 1, the solution of zinc sulfate suction liquid-phase precipitation device, after mixing while stirring, transferring mixed liquor volume with clean tap water is 450L, continues to stir.
(2) add 9mL/L activator, 2g/L metal zinc and 0.025mL/L brightener by above-mentioned mixed liquor volume.
(3) continue to stir and add the 100kg reduced iron powder, stop after 15 minutes stirring, (at this moment a lot of minute bubbles have appearred in solution surface, and copper, two kinds of metals of zinc have been deposited in the ferrous powder granules surface, color gray or redness), allow the solution natural subsidence.
4, after solution sinks clearly, remove most of supernatant with the suction of siphon method, put into centrifuge dewatering operation 10-20 minute, remove most of moisture content, taking-up is sub-packed in the stainless steel disc, sends into baking oven through 70-200 ℃, 20-40 minute drying processing.
5, with dry grey or kermesinus powder; the burning of packing into boat is sent in the heat-treatment furnace of reduction protection atmosphere; through 430-700 ℃, 20-70 minute heat treatment; copper, two kinds of metal diffusions of zinc are merged on iron matrix powder particles surface; (at this moment zinc and copper have formed alloy); obtain yellow, golden yellow or red brass coating layer, the iron-based brassiness powder that is slightly lumpd.
6, the iron-based brassiness powder of slight caking is through smashing to pieces, after the fragmentation, by the user demand of material granule degree being sieved.
7, the iron-based brassiness powder through sieving is packed into and is mixed in the powder machine, and to the product apparent density, the requirement of flowability etc. under the condition of mixing 18-25 rev/min in powder machine, mixed 3-19 minute, pressed control gauge and then carried out inspection by sampling by the user.
8, inspection by sampling qualified after, press the 25kg/ bag, the packing of checking the weight becomes product warehousing.
Claims (8)
1, a kind of iron-based brassiness powder metallurgy material, it is to adopt liquid-phase precipitation method, coat layer of copper, zinc composite bed on the ferrous powder granules surface equably,, make copper, two kinds of metal diffusions of zinc be fused to the iron-based grains surface and the powdered metallurgical material of formation through dehydration, oven dry heat treatment, it is made up of iron, copper and zinc, their content is as follows, and in 100 parts of the weight of iron powder, copper is the 3-25% of iron powder weight, zinc is the 3-40% of weight of copper, and all the other are iron powder.
2, the preparation method of the described iron-based brassiness powder metallurgy material of claim 1:
1) preparation of liquid-phase precipitation solution:
Mantoquita, 0.5-40kg zinc sulfate with iron powder weight 15-80kg with after the dissolving of 100kg running water, filters stand-by respectively respectively;
2) preparation of brightener:
300-500mL formaldehyde and the dissolving of 10-50g thiocarbamide is stand-by;
3) copper, zinc co-precipitation are on the ferrous powder granules surface
(1) with in the copper-bath of step 1), the solution of zinc sulfate suction liquid-phase precipitation device, mixes while stirring, transfer mixed liquor volume to 400-450L, continue to stir with clean tap water;
(2) add activator by above-mentioned mixed solution 5-9mL/L, press 0.5-2g/L and add toner, and press 0.01-0.025mL/L adding brightener;
(3) continue to stir and add the 100kg reduced iron powder, on the ferrous powder granules surface, color gray or redness allow the solution natural subsidence until copper, two kinds of precipitated metals of zinc;
4) after solution sinks clearly, inhale and remove supernatant, put into centrifuge dewatering, remove moisture content, take out and carry out the drying processing;
5) with dry grey or kermesinus powder, send in the heat-treatment furnace of reduction protection atmosphere, through 430-700 ℃ of heat treatment, two kinds of metals diffusions of copper, zinc are merged on iron matrix powder particles surface, obtain having yellow, golden yellow or the red iron-based brassiness powder brass coating layer, that slightly lump;
6) iron-based brassiness powder that will slightly lump is through smashing to pieces, after the fragmentation, by the user demand of material granule degree being sieved;
7) iron-based brassiness powder through sieving again by the requirement of user to product apparent density, flowability etc., mixes with mixing the powder machine, after inspection by sampling is qualified, and packing, warehouse-in.
3, the preparation method of iron-based brassiness powder metallurgy material according to claim 2 is characterized in that: described mantoquita adopts copper chloride, cupric pyrophosphate or copper sulphate.
4, according to the preparation method of claim 2 or 3 described iron-based brassiness powder metallurgy materials, it is characterized in that: described activator adopts sulfuric acid.
5, the preparation method of iron-based brassiness powder metallurgy material according to claim 4 is characterized in that: described toner adopts metal zinc.
6, the preparation method of iron-based brassiness powder metallurgy material according to claim 5 is characterized in that: described dry the processing adopted baking oven, and baking temperature is 70-200 ℃, time 20-40 minute.
7, the preparation method of iron-based brassiness powder metallurgy material according to claim 6 is characterized in that: described heat treatment time is 20-70 minute.
8, the preparation method of iron-based brassiness powder metallurgy material according to claim 7 is characterized in that: the rotating speed of described mixed powder machine is controlled at 18-25 rev/min, mixes 3-19 minute.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108273989A (en) * | 2017-12-22 | 2018-07-13 | 北京机科国创轻量化科学研究院有限公司 | A kind of high-temperature heat treatment method of metal alloy attritive powder anti-caking |
| CN108779523A (en) * | 2016-03-23 | 2018-11-09 | 霍加纳斯股份有限公司 | Iron-based powder |
| CN110596089A (en) * | 2019-10-09 | 2019-12-20 | 无锡通测检测技术有限公司 | Rapid nondestructive testing method for martensitic stainless steel part welding repair material |
| CN111451519A (en) * | 2020-04-03 | 2020-07-28 | 龙门金南磁性材料有限公司 | Preparation method of brass-coated iron powder |
| CN113751712A (en) * | 2021-08-19 | 2021-12-07 | 枣庄市鲁州粉末冶金制品有限公司 | Powder metallurgy brass bearing retainer and preparation process thereof |
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2008
- 2008-04-22 CN CNA2008100695749A patent/CN101254542A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108779523A (en) * | 2016-03-23 | 2018-11-09 | 霍加纳斯股份有限公司 | Iron-based powder |
| CN108273989A (en) * | 2017-12-22 | 2018-07-13 | 北京机科国创轻量化科学研究院有限公司 | A kind of high-temperature heat treatment method of metal alloy attritive powder anti-caking |
| CN108273989B (en) * | 2017-12-22 | 2020-01-21 | 北京机科国创轻量化科学研究院有限公司 | High-temperature heat treatment method for preventing metal alloy fine powder from caking |
| CN110596089A (en) * | 2019-10-09 | 2019-12-20 | 无锡通测检测技术有限公司 | Rapid nondestructive testing method for martensitic stainless steel part welding repair material |
| CN110596089B (en) * | 2019-10-09 | 2022-02-11 | 无锡通测检测技术有限公司 | Rapid nondestructive testing method for martensitic stainless steel part welding repair material |
| CN111451519A (en) * | 2020-04-03 | 2020-07-28 | 龙门金南磁性材料有限公司 | Preparation method of brass-coated iron powder |
| CN111451519B (en) * | 2020-04-03 | 2022-10-14 | 龙门金南磁性材料有限公司 | Preparation method of brass-coated iron powder |
| CN113751712A (en) * | 2021-08-19 | 2021-12-07 | 枣庄市鲁州粉末冶金制品有限公司 | Powder metallurgy brass bearing retainer and preparation process thereof |
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