CN100424366C - Multilayered self-lubricating material with high porosity and preparation method thereof - Google Patents
Multilayered self-lubricating material with high porosity and preparation method thereof Download PDFInfo
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- CN100424366C CN100424366C CNB2006100517032A CN200610051703A CN100424366C CN 100424366 C CN100424366 C CN 100424366C CN B2006100517032 A CNB2006100517032 A CN B2006100517032A CN 200610051703 A CN200610051703 A CN 200610051703A CN 100424366 C CN100424366 C CN 100424366C
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Abstract
The present invention discloses a multilayer compound self-lubricating material with high degree of porosity, which uses low carbon steel plates as a base material. Electro-coppering processing is carried out to the surface of the plate; then copper alloy powder with certain degree of porosity is sintered on the surface of a back lining layer of the plate; then a sintering polymeric material is laid and sintered on the surface of the copper alloy powder; the plate is rolled, the thickness of the plate is adjusted, and the self-lubricating material is made. The weight content of tin in the copper alloy powder is from 1% to 15%, and the value is preferably from 8% to 12%. The weight content of zinc is from 0% to 6%. The weight content of lead is from 0% to 6%, and the value is preferably from 3% to 5%. The present invention has the advantages of good mechanical performance, excellent self lubricity, excellent abrasive resistance, high productive efficiency and low manufacture cost, can keep the carrying capacity and the mechanical strength of the back lining metal material, etc. The present invention can be widely applied to lubricating components in turbine compressors.
Description
Technical field
The present invention relates to a kind of self lubricating material and preparation method thereof, especially a kind of have highly porous multilayered self-lubricating material and preparation method thereof.
Background technique
Need reliable and stable lubricating during compressor operating.When compressor lacks oiling agent or lubricated when unreasonable, compressor inside will produce serious abnormal sound, also can cause the wear out failure of compressor part when serious.For guaranteeing the stability of compressor moving element, need cut or abrasive machining the self oiling bearing surface, in case cause compressor to produce excessive noise owing to bearing wear produces excessive gap.Because bearing mainly is a long-play under the condition of condition of boundary lubrication and oil starvation or few fuel feeding, thereby the sliding bearing that development has good self-lubricating property and long lifetime stability seems extremely important.
Chinese invention patent (the publication number CN1292852A that U.S. Dana Corp proposes, patent name is " sliding bearing ") the spherical copper alloy powder of utilization, by sintering under the uniform temperature on the copper clad steel plate, sintering is the macromolecular material of main resin with polytetrafluoroethylene (PTFE) on the surface, makes bearing by rolling technology.The shortcoming of this invention is because porosity ratio is less, after high carrier strip spare lower surface polymer modification layer wearing and tearing, though can keep the stable wearing and tearing phase of a period of time, but prolonged exercise along with bearing, the metal that exposes on the frictional interface increases gradually, cause bearing life sharply to descend, and easy interlock antithesis friction pair.
(application number is USP5217814 to the U. S. Patent of Japan Taiho Kogyo Co.Ltd application, name is called " Sintered Sliding Material ") to utilize particle diameter be that the copper of 30～200 μ m or copper alloy powder sintering are on surface of steel plate, the alloy-layer porosity ratio that guarantees sintering is 5～70%, the polyflon that surface layer sintering molybdenum disulfide and lead powder etc. are filled, thereby prepare sliding material, can significantly improve the wear resistance of material.
(application number is USP5447774 to the U. S. Patent of Japan Daido Metal company application, name is called " Composite Sliding Member with High Porosity Sintering Layer ") with the alloyed copper powder sintering of low bulk density on sheet metal, the porosity ratio of alloy-layer reaches 50～80% behind the assurance sintering, surperficial then upward the covering with teflon is the macromolecule modified layer of main resin, guarantee that by the rolling again technology of sintering polyflon embeds in the alloyed powder, by rolling the preparation self oiling bearing, can improve the wear resistance of bearing effectively.
But the deficiency of above-mentioned these inventions is higher porosity and can causes the adhesive property of metal alloy powder and sheet metal to descend, thereby causes the bearing capacity of alloy-layer to descend.Simultaneously,, be not exposed to the surface of alloy-layer fully, cause the surface aggregate thing to infiltrate because the part hole is a closed pore.In addition, because main oiling agent is the paste based on the PTFE emulsion, make the moisture in the paste enter between hole, though moisture can evaporate after drying, but having viscoelastic polymer material also is difficult for embedding in the hole fully, thereby can't obtain excellent self lubricity and wear-resisting property, and the mechanical property of material is on a declining curve.
Summary of the invention
Technical problem to be solved by this invention is to propose a kind of the highly porous multilayered self-lubricating material of having of excellent self lubricity and wear resistance is arranged, and this preparation methods.
For solving the problems of the technologies described above, the present invention is a kind of, and to have highly porous multilayered self-lubricating material be base material with the low carbon steel plate, the surface is carried out electro-coppering and is handled, sintering has the certain porosity copper alloy powder on its back sheet surface then, again at shop, surface upside down firing knot polymer material, by making behind the rolling adjustment thickness, the weight content of tin is 1～15% in the described copper alloy powder, and preferred value is 8～12%; The weight content of zinc is 0～6%; Plumbous weight content is 0～6%, and preferred value is 3～5%.
Above-mentioned a kind of highly porous multilayered self-lubricating material that has, the bulk density of alloy-layer is 2.0～4.0g/cm behind the described bronze powder sintering
3, preferred value is 2.8～3.4g/cm
3
Above-mentioned a kind of highly porous multilayered self-lubricating material that has, described polymer material is main resin with polytetrafluoroethylene (PTFE), its composition and weight content are respectively: (1), teflon, weight content are 20～99%; (2), other organic fluorine, adopt in Meltability polytetrafluorethyletubular (PFA), the perfluoroethylene-propylene (FEP) one or both, weight content is 0.1～20%; (3), fiber, adopt a kind of in glass fibre, carbon fiber, aromatic polyamide fiber (as Kevlar fiber, Technora fiber or Twaron fiber) or the potassium titanate crystal whisker, weight content is 0.1～15%; (4), solid lubricant, adopt molybdenum disulfide or graphite, weight content is 0.1～30%; (5), mineral powder with collaborative lubrication adopts fillers such as metal fluoride, metal sulfate and metal phosphate, weight content is 0.1～15%.
Above-mentioned a kind of highly porous multilayered self-lubricating material that has, the diameter of described fiber≤8 μ m, average fiber length is below the 50 μ m, slenderness ratio is 2: 1 to 5: 1.
A kind of preparation method of the present invention with highly porous multilayered self-lubricating material, it comprises the following steps: 1, with mechanical mixer organic fluorine, fiber, solid lubricant and mineral powder is fully mixed stirring, put into baking oven then, mixture is carried out drying process under 120～200 ℃ condition, the moisture of mixture is sloughed; 2, will slough that mixture behind the water is put into taper or the biconial mixer mixes, and add a certain amount of lubricant oil, with the effect that guarantees to mix; 3, the material shop that mixes is overlying on the low carbon steel plate or copper coin surface that sinters copper powder; by rolling; mixture is rolled in the alloy-layer; be placed on then in the continous way sintering furnace; carry out sintering under the nitrogen protection condition, temperature is controlled in 360～420 ℃ of scopes, and the time is 5～30 minutes; again through rolling, make the present invention and have highly porous multilayered self-lubricating material after coming out of the stove.
Above-mentioned a kind of preparation method with highly porous multilayered self-lubricating material, described copper powder sintering 5～30 minutes under 750～920 ℃ of temperature conditions is to guarantee with Copper Plated Steel good binding intensity being arranged; The bulk density of alloy-layer is controlled at 2.0～4.0g/cm behind the sintering
3, its preferred value is 2.8～3.4g/cm
3
Utilize the prepared composite material of the present invention,, can be made into sliding bearing or thrust washer by series of processes such as cut-out, jet-bedding, volume circle, shaping, chamfering, polishing, plating.It adopts low carbon steel plate or copper coin as back sheet, and surface electrical copper facing or Cuprum alloy can guarantee to possess good cohesion with the alloy copper powder.It has good mechanical property, can keep the bearing capacity and the mechanical strength of backing metallic material, self lubricity and excellent in abrasion resistance, manufacturing efficiency height, advantages such as low cost of manufacture.Concrete physical and mechanical properties such as following table:
| Test event | Performance index |
| Serviceability temperature | -200～260℃ |
| Maximum load-carrying capacity | ＞130MPa |
| Maximum PV value | 60MPam/s (oil lubrication) |
| The friction and wear behavior of material (MM-200 type ring block type friction wear testing machine: load 200N, speed is 0.419m/s, dry friction, atmosphere environment) | Friction factor :≤0.15 wearing and tearing width:＜3.2mm |
| The friction and wear behavior of surface cut 0.15m rear bearing (bearing rotary test rig: load 2MPa, linear velocity 3.85m/s, oil lubrication, time 60min) | Friction factor :≤0.15 linear abrasion amount :≤0.01mm |
Composite material of the present invention can guarantee good dimensional stability, has lower noise when turning round for a long time.Material still can keep excellent abrasive through skiving or more than the cutting 0.15mm, thereby can be widely used in the slide member in the turbocompressor.Fiber of the present invention has good wear resistance, is difficult for producing the wearing and tearing on antithesis surface.The solid lubricant that is adopted has good lubricity, and with teflon good collaborative lubricating effect is arranged.Powder filler and teflon that the present invention added have good synergistic, can promote the adhesion of PTFE at the antithesis surface of friction pair effectively, reduce friction temperature effectively.
Embodiment:
Embodiment 1:
The surperficial sintered copper alloy powder of low carbon steel (thickness is 2.1mm) in electro-coppering; tin content is 12wt% in the copper alloy powder; zinc content is 3wt%; lead content is 3wt%; above-described copper alloy powder is evenly applied on the copper facing low carbon steel plate shop; guarantee that shop powder thickness is 0.35mm, in 900 ℃ of sintering 10min, the back of coming out of the stove guarantees that copper powder and Copper Plated Steel have good binding intensity under decomposed ammonia body protective condition.
By the proportioning that following surface lubrication material (polymer material) is implemented in formula table the 1st row each component is mixed in mechanical agitator, guarantee uniformity of mixture.Put into baking oven then, mixture is carried out drying process under 200 ℃ condition, the moisture of mixture is sloughed.Mixture behind the water is put into taper or the biconial mixer mixes with sloughing, and adds No. 45 machinery oil of 1/5 volume ratio.Subsequently the material shop that mixes is overlying on the metal sheet surface of the copper powder that has sintered; by rolling; mixture is rolled in the alloy-layer; THICKNESS CONTROL after rolling is placed in the continous way sintering furnace then at 2.50mm; under the nitrogen protection condition, carry out sintering in 420 ℃; time is 20 minutes, again through rolling, can prepare the multilayer materials that meets thickness deviation after coming out of the stove.
Embodiment 2:
At the surperficial sintered copper alloy powder of low carbon steel (thickness is 2.1mm) of electro-coppering, tin content is 8wt% in the copper alloy powder, and zinc content is 5wt%, and above-described copper alloy powder is evenly applied on the copper facing low carbon steel plate shop, guarantees that shop powder thickness is 0.35mm, at NH
3In 910 ℃ of sintering 15min, the back of coming out of the stove guarantees that copper powder and Copper Plated Steel have good binding intensity under the decomposition atmosphere protection condition.
Following surface lubrication material (polymer material) is implemented the proportioning of formula table the 2nd row each component is mixed in mechanical agitator, and detailed process is identical with exemplifying embodiment 1.
Embodiment 3:
At the surperficial sintered copper alloy powder of low carbon steel (thickness is 2.1mm) of electro-coppering, tin content is 10wt% in the copper alloy powder, and lead content is 5wt%, and above-described copper alloy powder is evenly applied on the copper facing low carbon steel plate shop, guarantees that shop powder thickness is 0.35mm, at NH
3In 860 ℃ of sintering 20min, the back of coming out of the stove guarantees that copper powder and Copper Plated Steel have good binding intensity under the decomposition atmosphere protection condition.
Following surface lubrication material (polymer material) is implemented the proportioning of formula table the 3rd row each component is mixed in mechanical agitator, and detailed process is identical with exemplifying embodiment 1.
Embodiment 4:
At the surperficial sintered copper alloy powder of low carbon steel (thickness is 2.1mm) of electro-coppering, tin content is 6wt% in the copper alloy powder, and zinc content is 6wt%, lead content is 3wt%, above-described copper alloy powder is evenly applied on the copper facing low carbon steel plate shop, guarantee that shop powder thickness is 0.35mm, at NH
3In 870 ℃ of sintering 15min, the back of coming out of the stove guarantees that copper powder and Copper Plated Steel have good binding intensity under the decomposition atmosphere protection condition.
Following surface lubrication material (polymer material) is implemented the proportioning of formula table the 4th row each component is mixed in mechanical agitator, and detailed process is identical with exemplifying embodiment 1.
Embodiment 5:
At the surperficial sintered copper alloy powder of low carbon steel (thickness is 2.1mm) of electro-coppering, the component content of copper alloy powder is identical with exemplifying embodiment 1 with implementation methods.
Following surface lubrication material (polymer material) is implemented the proportioning of formula table the 5th row each component is mixed in mechanical agitator, and detailed process is identical with exemplifying embodiment 1.
Embodiment 6:
At the surperficial sintered copper alloy powder of low carbon steel (thickness is 2.1mm) of electro-coppering, the component content of copper alloy powder is identical with exemplifying embodiment 2 with implementation methods.
Following surface lubrication material (polymer material) is implemented the proportioning of formula table the 6th row each component is mixed in mechanical agitator, and detailed process is identical with exemplifying embodiment 1.
Embodiment 7:
At the surperficial sintered copper alloy powder of low carbon steel (thickness is 2.1mm) of electro-coppering, the component content of copper alloy powder is identical with exemplifying embodiment 3 with implementation methods.
Following surface lubrication material (polymer material) is implemented the proportioning of formula table the 7th row each component is mixed in mechanical agitator, and detailed process is identical with exemplifying embodiment 1.
Surface lubrication material (polymer material) is implemented formula table
Claims (1)
1. one kind has highly porous multilayered self-lubricating material, it is base material with the low carbon steel plate, the surface is carried out electro-coppering and is handled, sintering has the certain porosity copper alloy powder on its back sheet surface then, again at shop, surface upside down firing knot polymer material, by making behind the rolling adjustment thickness, it is characterized in that, described polymer material is main resin with teflon, and its composition and weight content are respectively: (1), teflon, weight content are 20～99%; (2), other organic fluorine, adopt Meltability polytetrafluorethyletubular, weight content is 0.1～20%; (3), fiber, adopt a kind of in glass fibre, carbon fiber or the potassium titanate crystal whisker, weight content is 0.1～15%; (4), solid lubricant, adopt graphite, weight content is 0.1～30%; (5), mineral powder with collaborative lubrication, adopt a kind of in metal fluoride, metal sulfate and the metal phosphate, weight content is 0.1～15%; The weight content of tin is 8～12% in the described copper alloy powder, and the weight content of zinc is 0～6%; Plumbous weight content is 3～5%.
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| CN100424366C true CN100424366C (en) | 2008-10-08 |
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| US5039575A (en) * | 1987-10-20 | 1991-08-13 | Daido Metal Company Ltd. | Single body and composite sliding members |
| US5217814A (en) * | 1991-02-09 | 1993-06-08 | Taiho Kogyo Co., Ltd. | Sintered sliding material |
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| CN1884865A (en) | 2006-12-27 |
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