EP0022869B1 - Procede de production d'un alliage d'aluminium contenant du graphite - Google Patents
Procede de production d'un alliage d'aluminium contenant du graphite Download PDFInfo
- Publication number
- EP0022869B1 EP0022869B1 EP79900934A EP79900934A EP0022869B1 EP 0022869 B1 EP0022869 B1 EP 0022869B1 EP 79900934 A EP79900934 A EP 79900934A EP 79900934 A EP79900934 A EP 79900934A EP 0022869 B1 EP0022869 B1 EP 0022869B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- graphite particles
- melt
- aluminium
- alloy
- graphite
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C32/00—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ
- C22C32/0084—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ carbon or graphite as the main non-metallic constituent
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/10—Alloys containing non-metals
- C22C1/1036—Alloys containing non-metals starting from a melt
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/02—Making non-ferrous alloys by melting
- C22C1/026—Alloys based on aluminium
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/12—All metal or with adjacent metals
- Y10T428/12486—Laterally noncoextensive components [e.g., embedded, etc.]
Definitions
- the present invention relates to a process for the preparation of aluminum alloys containing graphite, which comprises adding and dispersing particles of raw natural graphite, not covered with a metal, in a casting of aluminum or an alloy of this type. latest.
- metal alloys containing a solid lubricant have been used. This method is used to compensate for a loss of lubrication by providing a self-lubricating action of the solid lubricant when a film of a lubricating oil is destroyed.
- graphite is very suitable as a solid lubricant. Consequently, numerous alloys containing graphite particles have been proposed and manufactured to date. However, most of these metal alloys containing graphite particles are prepared according to a spray metallurgy, so that the resulting sintering products do not have sufficient mechanical properties.
- a method has therefore been proposed according to which a mixed powder of graphite particles coated with nickel and a halide is incorporated into a casting of an AI-Si hypereutectic alloy and vortices are formed in the casting by an agitator for uniformly dispersing the graphite particles, and another method in which graphite particles coated with a metal and suspended in a carrier gas are blown in a cast of an aluminum alloy, method described in the publication JP- B-45-13224.
- a metallic coating can be formed on the surfaces of the graphite particles by chemical plating or the like.
- this process involves complicated stages, the installations for treating waste water and the like pose major problems and consequently the cost prices of these products are unfavorably increased.
- the process using the mixed powder requires considerable time for this mixing, and it is very difficult to choose a suitable particle size to mix the graphite particles to be dispersed in the casting. If a carrier gas is used, the graphite particles which can be used are limited to very fine particles, and a long time is required to determine the dispersion of a predetermined amount of the graphite particles.
- the object of the present invention is to propose a process for the preparation of aluminum alloys containing graphite, according to which graphite particles of 2 to 30% by weight are thrown and dispersed in a very short time in aluminum castings or alloys of the latter, with adequate efficiency of use.
- Another object of the invention is to propose a process for the preparation of aluminum alloys containing graphite, which uses graphite particles not covered with a metal so that it is possible to use crude graphite particles for reduce manufacturing costs.
- Another object of the invention is to propose a process for the preparation of aluminum alloys containing graphite, according to which the casting structure is made fine and the graphite particles are not likely to float on the surface of the casting.
- One of the characteristics of the invention resides in a process for the preparation of aluminum alloys containing graphite, which comprises the following steps: incorporation, for example by throwing away from 1.5 to 20%, by weight, of at least one additive metal chosen from the group: titanium (Ti), chromium (Cr), zirconium (Zr), nickel (Ni), vanadium (V), cobalt (Co), manganese (Mn) and niobium (Nb), in a casting aluminum or an alloy thereof, after introduction of said metal, launch and dispersion of 2 to 30%, by weight, of particles of raw natural graphite without metallic coating inside the casting and after that, solidification of casting aluminum or aluminum alloy containing these graphite particles.
- Another characteristic of the invention lies in the stage of solidification of the casting under a pressure of 400 to 1000 kg / cm 2 to make the sintered structure very fine and to suppress the flotation of the graphite particles.
- an aluminum casting alloy in which the graphite particles are substantially and uniformly dispersed throughout the structure of the refined ingot, the metallic coating on the surface of the graphite particles is removed and the buoyancy of the latter is reduced.
- the resulting aluminum alloy containing the graphite particles is melted again, these particles do not float on the surface of the casting.
- the drawing is a simple figure showing the relationship between the dispersed amount of the graphite particles and the particle size thereof when additive metals are incorporated into a casting of aluminum alloy by varying the amount of these additive metals.
- an aluminum alloy in which graphite particles are thrown and dispersed contains at least one of the following elements: tin (Sn), copper (Cu), lead (Pb) and silicon (Si).
- tin (Sn), copper (Cu), lead (Pb) and silicon (Si) The reason for using such alloys is to further improve the usability of these, when graphite particles are dispersed in alloys of AI-Sn, AI-Cu, AI-Pb and AI-Si , alloys widely used so far in bearings or the like.
- At least one element chosen from the group: Ti, Cr, Zr, V, Nb, Ni, Co, Mn and P is incorporated into said casting. These elements were chosen on the basis of experimental results.
- graphite particles are incorporated in an amount varying by weight, from 2 to 30%, the highest lubrication effect can be obtained when the product is used under dry friction. It is difficult to obtain a sufficient lubricating effect with an incorporation of less than 2% by weight of the graphite particles. While, when the graphite particles are used in an amount greater than 30% by weight, the mechanics also decrease.
- the graphite particles are incorporated in the range of 2 to 30% by weight, it is desirable that at least one of the elements: Ti, Cr, Zr, Ni, V, Co, Mn or Nb is first incorporated in the casting in an amount varying, by weight, from 1.5 to 20%. If such elements are incorporated in a total amount greater than 20% by weight, although the effect of preventing the flotation of graphite can be achieved, there is a risk of seeing some unexpected defects appear if the resulting molded alloy is used for a bearing or a piston.
- the resulting aluminum alloys containing the graphite are suitable as metallic elements to be used at low load and at high speed.
- the resulting aluminum alloys are suitable as metallic elements to be used under conditions of friction by lubricant, because the parts containing graphite are effective in providing an oil sink.
- the graphite can also advantageously be incorporated in an amount of 15 to 20% by weight.
- the temperature of the casting into which the graphite particles are thrown is between a value greater than 50 ° C relative to the liquidus and approximately 900 ° C.
- the temperature is not maintained above this level 50 ° C higher than the liquid, the fluidity of the casting degrades and faults such as blowing are likely to form.
- the liquid is approximately at 570 ° C with an AI-Si alloy containing 12%, by weight, of Si, at 700 ° C with an Ai-Si alloy containing 20%, by weight of Si, at 640 ° C with an alloy AI-Sn containing 10%, by weight, of Sn and at 650 ° C. with an AI-Cu alloy containing 4%, by weight, of Cu. It is recommended to add Cu, Mg, Ni, Zn, Mn or Pb, and similar alloying elements in small amounts to these two element-matrix systems to strengthen the matrix.
- the liquidus temperature changes according to the quantity of elements added to suppress the buoyancy of the graphite particles and if these graphite particles are added adequately to prevent them from floating, the temperature changes only by ⁇ 200 ° C.
- the casting immediately before the incorporation of the graphite particles, is maintained either at rest or agitated. When the casting is kept at rest, it must be stirred after incorporating the graphite particles. In any case, once the graphite particles are incorporated, they are suspended in the eddies of the casting, produced by stirring, so as to facilitate their dispersion.
- This operation is very important because, otherwise, one cannot obtain a molded ingot in which the graphite particles are uniformly dispersed.
- a pressure of 400 to 1000 kg / cm 2 is desirable to achieve solidification. If this pressure is less than 400 kg / cm 2 , you cannot extract enough gas. If, on the contrary, it is greater than 1000 kg / cm 2 , such a high pressure requires too large a device, thereby increasing the costs of this apparatus.
- the latter In the aluminum alloy containing graphite, the latter generally acts as a solid lubricant and greatly contributes to improving the abrasion resistance. This action is influenced by the size of the graphite particles used.
- the mean diameter of the graphite particles is desirable for the mean diameter of the graphite particles to be used to be 50 ⁇ m.
- the degree of dispersion of the graphite particles is influenced by the speed of agitation of the casting. For example, an aluminum alloy containing, by weight, 12% of Si and 3% of Cr is melted and maintained at a temperature of 700 ° C in a graphite crucible of 90 mm in diameter. The casting is then stirred using paddles at different speeds, and powder is added. natural graphite of 60 to 80 meshes in the casting, in an amount equal to 9%, by weight, then the dispersion of the graphite particles is observed.
- pulverized natural graphite 177 to 250 ⁇ m in size is added to the casting, in an amount of 9% by weight.
- One of the following elements is incorporated into the casting: Ti, Cr, Zr, V, Ni, Co, Mn and Nb, and the quantity of such an incorporated additive element is changed to determine the quantity of the necessary additive element to disperse up to 30% by weight of graphite particles without causing them to float.
- the measured results are shown in Table 1. It can be seen there that if the casting contains one of these elements in an amount of 1 to 20%, by weight, the graphite particles can be incorporated between 2 and 30% in weight. In this process, solidification under pressure takes place at 600 kg / cm 2 .
- the aluminum casting containing the graphite is then solidified under a pressure of 600 kg / cm 2 and an aluminum alloy containing graphite is thus produced.
- An AI-Cu-Zr alloy containing, by weight, 50% Cu and 3% Zr is melted in a graphite crucible with an internal diameter of 90 mm inside diameter and the resulting casting is maintained at a temperature of 750 ° C.
- a pallet-shaped element is introduced into the crucible with which the AI-Cu-Zr alloy will be rotated and stirred at 100 revolutions / minute to form vortices in the casting.
- region 1 represents a flotation region of graphite and region II a dispersion region of graphite. It will be seen there that the quantity of dispersed graphite changes according to the quantity of the additive element added and that the graphite is likely to float on the surface of the casting according to its particle size.
- An AI-Si alloy containing, by weight, 12% of Si is melted in a graphite crucible with an inside diameter of 90 mm, and 0.1, 0.5, 1.0, 2 are added to this flow, respectively. , 0, 3.0 and 4.0%, by weight, of phosphorus. Then, the flows are maintained at a temperature of 700 ° C.
- Graphite particles from 177 to 250 ⁇ m in size are added to the casting, at a rate of 2% by weight, in order to determine the quantitative limit of the dispersed graphite particles as a function of each casting.
- the quantitative limit of the graphite particles dispersed is determined by an identical process with an AI-Si alloy containing, by weight, 20% of Si, an AI-Sn alloy containing, by weight, 5% of Sn and an AI-Cu alloy. containing, by weight, 4% Cu.
- Table 2 On the latter, it can be seen that the limit quantity of the dispersed graphite particles is influenced by the quantity of phosphorus but not by the matrix.
- an amount greater than 30%, by weight, of graphite particles, 3.0 to 4.0%, by weight, of phosphorus can be added.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacture Of Alloys Or Alloy Compounds (AREA)
- Powder Metallurgy (AREA)
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9722778A JPS5524949A (en) | 1978-08-11 | 1978-08-11 | Manufacture of graphite-containing aluminium alloy |
| JP97227/78 | 1978-08-11 |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| EP0022869A4 EP0022869A4 (fr) | 1980-12-12 |
| EP0022869A1 EP0022869A1 (fr) | 1981-01-28 |
| EP0022869B1 true EP0022869B1 (fr) | 1983-08-03 |
Family
ID=14186735
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP79900934A Expired EP0022869B1 (fr) | 1978-08-11 | 1979-08-09 | Procede de production d'un alliage d'aluminium contenant du graphite |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US4383970A (cs) |
| EP (1) | EP0022869B1 (cs) |
| JP (1) | JPS5524949A (cs) |
| DE (1) | DE2953015C1 (cs) |
| GB (1) | GB2039961B (cs) |
| WO (1) | WO1980000352A1 (cs) |
Families Citing this family (27)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4759995A (en) * | 1983-06-06 | 1988-07-26 | Dural Aluminum Composites Corp. | Process for production of metal matrix composites by casting and composite therefrom |
| US4786467A (en) * | 1983-06-06 | 1988-11-22 | Dural Aluminum Composites Corp. | Process for preparation of composite materials containing nonmetallic particles in a metallic matrix, and composite materials made thereby |
| CA1289748C (en) * | 1985-03-01 | 1991-10-01 | Abinash Banerji | Producing titanium carbide |
| JPH0630794B2 (ja) * | 1985-10-14 | 1994-04-27 | 栗田工業株式会社 | 半導体洗浄用超純水製造装置 |
| US4865806A (en) * | 1986-05-01 | 1989-09-12 | Dural Aluminum Composites Corp. | Process for preparation of composite materials containing nonmetallic particles in a metallic matrix |
| IN168301B (cs) * | 1986-09-02 | 1991-03-09 | Council Scient Ind Res | |
| GB8622458D0 (en) * | 1986-09-18 | 1986-10-22 | Alcan Int Ltd | Alloying aluminium |
| US6127047A (en) * | 1988-09-21 | 2000-10-03 | The Trustees Of The University Of Pennsylvania | High temperature alloys |
| US5028301A (en) * | 1989-01-09 | 1991-07-02 | Townsend Douglas W | Supersaturation plating of aluminum wettable cathode coatings during aluminum smelting in drained cathode cells |
| US5227045A (en) * | 1989-01-09 | 1993-07-13 | Townsend Douglas W | Supersaturation coating of cathode substrate |
| JPH03267355A (ja) * | 1990-03-15 | 1991-11-28 | Sumitomo Electric Ind Ltd | アルミニウム―クロミウム系合金およびその製法 |
| DE69219552T2 (de) * | 1991-10-23 | 1997-12-18 | Inco Ltd | Mit Nickel überzogene Vorform aus Kohlenstoff |
| US5236468A (en) * | 1992-03-19 | 1993-08-17 | J. S. Mccormick Company | Method of producing formed carbonaceous bodies |
| GB2267912A (en) * | 1992-06-15 | 1993-12-22 | Secr Defence | Metal matrix for composite materials |
| EP0582435B1 (en) * | 1992-08-06 | 1996-02-28 | Toyota Jidosha Kabushiki Kaisha | Method of producing TiC whiskers and metallic composite material reinforced by TiC whiskers |
| US5296056A (en) * | 1992-10-26 | 1994-03-22 | General Motors Corporation | Titanium aluminide alloys |
| US9963395B2 (en) | 2013-12-11 | 2018-05-08 | Baker Hughes, A Ge Company, Llc | Methods of making carbon composites |
| US9325012B1 (en) * | 2014-09-17 | 2016-04-26 | Baker Hughes Incorporated | Carbon composites |
| US10315922B2 (en) | 2014-09-29 | 2019-06-11 | Baker Hughes, A Ge Company, Llc | Carbon composites and methods of manufacture |
| US10480288B2 (en) | 2014-10-15 | 2019-11-19 | Baker Hughes, A Ge Company, Llc | Articles containing carbon composites and methods of manufacture |
| US9962903B2 (en) | 2014-11-13 | 2018-05-08 | Baker Hughes, A Ge Company, Llc | Reinforced composites, methods of manufacture, and articles therefrom |
| US9745451B2 (en) | 2014-11-17 | 2017-08-29 | Baker Hughes Incorporated | Swellable compositions, articles formed therefrom, and methods of manufacture thereof |
| US11097511B2 (en) | 2014-11-18 | 2021-08-24 | Baker Hughes, A Ge Company, Llc | Methods of forming polymer coatings on metallic substrates |
| US10300627B2 (en) | 2014-11-25 | 2019-05-28 | Baker Hughes, A Ge Company, Llc | Method of forming a flexible carbon composite self-lubricating seal |
| US10125274B2 (en) | 2016-05-03 | 2018-11-13 | Baker Hughes, A Ge Company, Llc | Coatings containing carbon composite fillers and methods of manufacture |
| US10344559B2 (en) | 2016-05-26 | 2019-07-09 | Baker Hughes, A Ge Company, Llc | High temperature high pressure seal for downhole chemical injection applications |
| CN106334787B (zh) * | 2016-10-24 | 2018-06-29 | 三峡大学 | 一种梯度石墨/铝基表层自润滑复合材料及制备方法 |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1207539A (en) * | 1966-10-07 | 1970-10-07 | Int Nickel Ltd | Graphitic aluminium alloys |
| FR95986E (fr) * | 1968-03-25 | 1972-05-19 | Int Nickel Ltd | Alliages graphitiques et leurs procédés de production. |
| CH515195A (fr) * | 1969-07-31 | 1971-11-15 | Battelle Memorial Institute | Matériau composite et procédé pour sa fabrication |
| US3753694A (en) * | 1970-07-06 | 1973-08-21 | Int Nickel Co | Production of composite metallic articles |
| JPS4918891B1 (cs) * | 1970-12-25 | 1974-05-14 | ||
| JPS5438125B2 (cs) * | 1971-08-24 | 1979-11-19 | ||
| JPS5523892B2 (cs) * | 1973-04-03 | 1980-06-25 | ||
| JPS5293621A (en) * | 1976-02-02 | 1977-08-06 | Hitachi Ltd | Production of copper alloy containing graphite |
| JPS5295503A (en) * | 1976-02-09 | 1977-08-11 | Hitachi Ltd | Production of alloy dispersed with metal particles |
-
1978
- 1978-08-11 JP JP9722778A patent/JPS5524949A/ja active Granted
-
1979
- 1979-08-09 DE DE2953015A patent/DE2953015C1/de not_active Expired
- 1979-08-09 GB GB8011125A patent/GB2039961B/en not_active Expired
- 1979-08-09 EP EP79900934A patent/EP0022869B1/fr not_active Expired
- 1979-08-09 WO PCT/JP1979/000211 patent/WO1980000352A1/ja not_active Ceased
- 1979-08-09 US US06/196,044 patent/US4383970A/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| EP0022869A4 (fr) | 1980-12-12 |
| US4383970A (en) | 1983-05-17 |
| JPS5524949A (en) | 1980-02-22 |
| JPS6158534B2 (cs) | 1986-12-12 |
| DE2953015C1 (de) | 1984-08-30 |
| WO1980000352A1 (fr) | 1980-03-06 |
| EP0022869A1 (fr) | 1981-01-28 |
| GB2039961B (en) | 1983-11-09 |
| GB2039961A (en) | 1980-08-20 |
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