JPH05190240A - Manufacture of electric brush and copper powder material for manufacturing electric brush - Google Patents
Manufacture of electric brush and copper powder material for manufacturing electric brushInfo
- Publication number
- JPH05190240A JPH05190240A JP4021587A JP2158792A JPH05190240A JP H05190240 A JPH05190240 A JP H05190240A JP 4021587 A JP4021587 A JP 4021587A JP 2158792 A JP2158792 A JP 2158792A JP H05190240 A JPH05190240 A JP H05190240A
- Authority
- JP
- Japan
- Prior art keywords
- copper powder
- electric brush
- electrolytic
- ultrafine
- particle size
- 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.)
- Pending
Links
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 title claims abstract description 68
- 238000004519 manufacturing process Methods 0.000 title claims description 10
- 239000000463 material Substances 0.000 title abstract 4
- 239000002245 particle Substances 0.000 claims description 20
- 239000002994 raw material Substances 0.000 claims description 14
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 6
- 229910002804 graphite Inorganic materials 0.000 claims description 3
- 239000010439 graphite Substances 0.000 claims description 3
- 238000005452 bending Methods 0.000 abstract description 10
- 230000003647 oxidation Effects 0.000 abstract description 9
- 238000007254 oxidation reaction Methods 0.000 abstract description 9
- 239000010949 copper Substances 0.000 abstract description 7
- 229910052802 copper Inorganic materials 0.000 abstract description 6
- 239000007770 graphite material Substances 0.000 abstract 1
- 238000005868 electrolysis reaction Methods 0.000 description 6
- 238000000034 method Methods 0.000 description 6
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 238000009826 distribution Methods 0.000 description 4
- 239000008151 electrolyte solution Substances 0.000 description 3
- 230000001771 impaired effect Effects 0.000 description 3
- 238000005065 mining Methods 0.000 description 3
- 238000007670 refining Methods 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- 239000000654 additive Substances 0.000 description 2
- 239000003963 antioxidant agent Substances 0.000 description 1
- 230000003078 antioxidant effect Effects 0.000 description 1
- QRUDEWIWKLJBPS-UHFFFAOYSA-N benzotriazole Chemical compound C1=CC=C2N[N][N]C2=C1 QRUDEWIWKLJBPS-UHFFFAOYSA-N 0.000 description 1
- 239000012964 benzotriazole Substances 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012776 electronic material Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000003973 paint Substances 0.000 description 1
- 238000004663 powder metallurgy Methods 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000010298 pulverizing process Methods 0.000 description 1
- 238000006722 reduction reaction Methods 0.000 description 1
- 239000012756 surface treatment agent Substances 0.000 description 1
- 238000004154 testing of material Methods 0.000 description 1
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は電刷子の製造方法及び電
刷子製造用銅粉原料に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an electric brush and a copper powder raw material for manufacturing the electric brush.
【０００２】[0002]
【従来の技術】銅粉は焼結含油軸受、焼結機械部品、金
属黒鉛刷子（電刷子）等の製造に用いれており、最近は
電子材料、例えば電磁波シールド（ＥＭＩ）用導電塗料
等の分野にも用途が広がっている。特に、電解銅粉は電
気分解において陰極に樹枝状に析出したもので粉末冶金
等の用途に最適のものである。2. Description of the Related Art Copper powder is used in the production of sintered oil-impregnated bearings, sintered machine parts, metal graphite brushes (electric brushes), etc., and recently in the field of electronic materials such as conductive paints for electromagnetic wave shielding (EMI). The application is expanding. In particular, electrolytic copper powder is deposited in a dendritic manner on the cathode during electrolysis and is most suitable for powder metallurgy and other applications.
【０００３】電刷子は抵抗率が低く且つ耐酸化性に優れ
ているだけでなく、曲げ強さにも優れていることが必要
である。電解銅粉の形状や粒度は電刷子の強度、特に曲
げ強さに大きく影響していると考えられており、それで
電解精錬の際の電解条件や添加物などによって形状や粒
度を制御している。The electric brush is required to have not only a low resistivity and an excellent oxidation resistance, but also an excellent bending strength. It is considered that the shape and particle size of electrolytic copper powder have a great influence on the strength of the electric brush, especially the bending strength, so the shape and particle size are controlled by the electrolytic conditions and additives during electrolytic refining. .
【０００４】[0004]
【発明が解決しようとする課題】しかし、電解銅粉の粒
度を変更するために電解条件を変更することは、現場的
な問題がある。又添加物を用いる場合には微量の添加で
電解銅粉の形状に影響を与えるので制御が困難であり、
常に一定の特性を有するものを得ることが困難である等
の問題がある。However, changing the electrolysis conditions to change the particle size of the electrolytic copper powder has a field problem. When using additives, it is difficult to control because the addition of a trace amount affects the shape of electrolytic copper powder.
There is a problem that it is difficult to obtain a product having constant characteristics.
【０００５】本発明の目的は、従来の電解銅粉を用いて
得た電刷子と比較して、抵抗率及び耐酸化性がほとんど
損なわれていないが、強度、特に曲げ強さが著しく増大
されている電刷子の製造方法及び該電刷子の製造に用い
る銅粉原料を提供することにある。The object of the present invention is that the electrical resistance and the oxidation resistance are hardly impaired, but the strength, especially the bending strength is remarkably increased, as compared with the electric brush obtained by using the conventional electrolytic copper powder. Another object of the present invention is to provide a method for producing an electric brush and a copper powder raw material used for producing the electric brush.
【０００６】[0006]
【課題を解決するための手段】本発明者らは、上記目的
を達成するために種々検討を重ねた結果、従来の電解銅
粉と所定粒度の極微細銅粉とを所定の比率で併用するこ
とにより、従来の電解銅粉を用いて得た電刷子と比較し
て、抵抗率及び耐酸化性がほとんど損なわれていない
が、強度、特に曲げ強さが著しく増大されている電刷子
が得られることを見出し、本発明を完成した。As a result of various studies to achieve the above object, the present inventors have used conventional electrolytic copper powder and ultrafine copper powder of a predetermined particle size together in a predetermined ratio. As a result, compared with the electric brush obtained by using the conventional electrolytic copper powder, the electric resistance and the oxidation resistance are hardly impaired, but the strength, particularly the bending strength is significantly increased. The present invention has been completed and the present invention has been completed.
【０００７】本発明の電刷子の製造方法は電解銅粉９６
〜８０重量％と平均粒径が１５μｍ以下である銅粉（以
下、極微細銅粉という）４〜２０重量％とからなる銅粉
原料及び黒鉛原料を用いることを特徴とする。The method for producing an electric brush of the present invention uses electrolytic copper powder 96
It is characterized by using a copper powder raw material and a graphite raw material consisting of ˜80 wt% and 4 to 20 wt% of copper powder having an average particle size of 15 μm or less (hereinafter referred to as ultrafine copper powder).
【０００８】また、本発明の電刷子製造用銅粉原料は電
解銅粉９６〜８０重量％と極微細銅粉４〜２０重量％と
からなることを特徴とする。Further, the copper powder raw material for producing an electric brush of the present invention is characterized by comprising 96 to 80% by weight of electrolytic copper powder and 4 to 20% by weight of ultrafine copper powder.
【０００９】本発明で用いる電解銅粉は市販の電解銅粉
であり、その平均粒径は一般的には２０〜５０μｍ程度
である。銅粉原料としてこのような電解銅粉のみを用い
て得られる電刷子の曲げ強さは必ずしも十分ではない。
このような電解銅粉と平均粒径が１５μｍ以下好ましく
は１２μｍ以下である極微細銅粉とを併用すると、極微
細銅粉比率の増加につれて電刷子の曲げ強さは増大し、
極微細銅粉の比率が４重量％以上で電刷子の曲げ強さの
有意の増大が認められる。しかし極微細銅粉は見掛密度
が小さいので、同じ重量でもより大きい容積量となり、
極微細銅粉の比率が大きくなるにつれてより大きい容積
量の銅粉原料を用いることになり、実用的でなくなる。
また極微細銅粉の比率が２０重量％を越えると電刷子の
耐酸化性が低下し、実用的でなくなり、またこの耐酸化
性の低下を防止するのに必要な量の酸化防止剤を用いる
と電刷子の抵抗率が高くなり、実用的でなくなる。従っ
て、本発明においては銅粉原料中の極微細銅粉の比率は
４〜２０重量％、好ましくは５〜１５重量％に限定され
る。The electrolytic copper powder used in the present invention is a commercially available electrolytic copper powder, and its average particle size is generally about 20 to 50 μm. The bending strength of an electric brush obtained by using only such electrolytic copper powder as a copper powder raw material is not always sufficient.
When such an electrolytic copper powder is used in combination with an ultrafine copper powder having an average particle size of 15 μm or less, preferably 12 μm or less, the bending strength of the electric brush increases as the ratio of the ultrafine copper powder increases,
When the ratio of the ultrafine copper powder is 4% by weight or more, a significant increase in bending strength of the electric brush is recognized. However, since the ultrafine copper powder has a low apparent density, it has a larger volume even with the same weight,
As the ratio of the ultrafine copper powder increases, a larger volume of copper powder raw material is used, which becomes impractical.
On the other hand, if the ratio of the ultrafine copper powder exceeds 20% by weight, the oxidation resistance of the electric brush is deteriorated and becomes impractical, and the amount of the antioxidant necessary for preventing the deterioration of the oxidation resistance is used. And the resistivity of the electric brush becomes high, making it impractical. Therefore, in the present invention, the ratio of the ultrafine copper powder in the copper powder raw material is limited to 4 to 20% by weight, preferably 5 to 15% by weight.
【００１０】本発明で用いる電解銅粉としては例えば下
記の特性を有する樹枝状電解銅粉（三井金属鉱業株式会
社製、ＭＮ−２）がある： 見掛密度 １．０５〜１．２５ｇ/cm3 平均粒径 ３３．０〜４０．０μｍ 粒度分布（メッシュ） ＋200 −200/＋250 −250/＋325 −325 （％） ＜5 5 〜 15 24 〜 32 50〜70 本発明で用いる極微細銅粉は平均粒径が１５μｍ以下で
ある限りは例えば機械的粉砕法、化学的還元法、電解法
等の何れの方法で得られたものでもよいが、特に次の方
法によって得られたものを用いることが好ましい：電解
液として電解尾液（銅の電解精錬を行っていると銅濃度
が段々高くなってくるので、銅濃度を調節するために希
硫酸を加えるが、これによって電解液量が増加するの
で、その増加分を取り出す。この取り出した電解液を電
解尾液という）を用い、陽極としてＰｂ電極を用い、陰
極としてＣｕ電極を用い、電解液を調整しないままで電
解を継続して銅を樹枝状電解銅粉として回収し、銅回収
後の電解液を希硫酸として電解精錬工程に循環させる。
電解尾液の電解においては銅濃度が段々薄くなっていく
ので、電解析出する銅粉は極微細になる。このような極
微細電解銅粉としては例えば下記の特性を有する樹枝状
電解銅粉がある： 見掛密度 ０．５５〜０．７０ｇ/cm3 平均粒径 ９．３０〜１０．３０μｍ 粒度分布（メッシュ） ＋200 −200/＋250 −250/＋325 −325 （％） ＜0.1 0.1〜0.4 1.5〜2.0 95〜98Examples of the electrolytic copper powder used in the present invention include dendritic electrolytic copper powder (MN-2 manufactured by Mitsui Mining & Smelting Co., Ltd.) having the following characteristics: Apparent density 1.05 to 1.25 g / cm 3 Average particle size 33.0 to 40.0 μm Particle size distribution (mesh) +200 −200 / + 250 −250 / + 325 −325 (%) <5 5 to 15 24 to 32 50 to 70 The ultrafine copper powder used in the present invention is As long as the average particle size is 15 μm or less, it may be obtained by any method such as mechanical pulverization method, chemical reduction method, electrolysis method, etc., but especially the one obtained by the following method is used. Preferred: Electrolytic tail solution as the electrolytic solution (Since the copper concentration gradually increases when electrolytically refining copper, dilute sulfuric acid is added to adjust the copper concentration, but this increases the amount of electrolytic solution. Then, take out the increased amount. ) Is used, a Pb electrode is used as an anode, a Cu electrode is used as a cathode, and electrolysis is continued without adjusting the electrolytic solution to recover copper as a dendritic electrolytic copper powder. It is circulated in the electrolytic refining process as sulfuric acid.
Since the copper concentration gradually decreases in the electrolysis of the electrolytic tail solution, the copper powder electrolytically deposited becomes extremely fine. Examples of such ultrafine electrolytic copper powder include dendritic electrolytic copper powder having the following characteristics: Apparent density 0.55 to 0.70 g / cm 3 Average particle size 9.30 to 10.30 μm Particle size distribution ( Mesh) +200 -200 / + 250 -250 / + 325 -325 (%) <0.1 0.1 ~ 0.4 1.5 ~ 2.0 95 ~ 98
【００１１】[0011]
実施例１〜３及び比較例１〜３ 電解銅粉として下記の特性を有する電刷子用樹枝状電解
銅粉（三井金属鉱業株式会社製、ＭＮ−２）を用いた： 見掛密度 １．２ｇ/cm3 平均粒径 ３６．３μｍ 粒度分布（メッシュ） ＋200 −200/＋250 −250/＋325 −325 （％） 3.0 10.1 26.6 60.3 極微細銅粉として電解尾液の電解で得た下記の特性を有
する樹枝状電解銅粉（三井金属鉱業株式会社製）を用い
た： 見掛密度 ０．６３ｇ/cm3 平均粒径 ９．８５μｍ 粒度分布（メッシュ） ＋200 −200/＋250 −250/＋325 −325 （％） 0.1 0.1 1.8 98.0 また、黒鉛粉として鱗状黒鉛粉（日本黒鉛粉工業株式会
社製、ＣＢ−１５０）を用いた。Examples 1 to 3 and Comparative Examples 1 to 3 As the electrolytic copper powder, a dendritic electrolytic copper powder for electric brushes (MN-2 manufactured by Mitsui Mining & Smelting Co., Ltd.) having the following characteristics was used: Apparent density 1.2 g / cm 3 Average particle size 36.3 μm Particle size distribution (mesh) +200 −200 / + 250 −250 / + 325 −325 (%) 3.0 10.1 26.6 60.3 As ultrafine copper powder, it has the following characteristics obtained by electrolysis of electrolytic tail solution Dendritic copper powder (manufactured by Mitsui Mining & Smelting Co., Ltd.) was used: Apparent density 0.63 g / cm 3 Average particle size 9.85 μm Particle size distribution (mesh) +200 −200 / + 250 −250 / + 325 −325 (% ) 0.1 0.1 1.8 98.0 As the graphite powder, scaly graphite powder (CB-150 manufactured by Nippon Graphite Powder Co., Ltd.) was used.
【００１２】上記の電解銅粉及び極微細銅粉を表面処理
剤ベンゾトリアゾールで処理した。それらの処理した銅
粉原料を表１に示す比率で用い、銅粉原料７０重量％と
上記の黒鉛粉３０重量％とからなる混合物を用いて、常
温でプレス圧２．５ｔ/cm2で加圧成形し、６００℃で焼
結して電刷子用成形体（厚さ約６mm、幅約１２mm、長さ
約３０mmの直方体）を得た。The above electrolytic copper powder and ultrafine copper powder were treated with a surface treatment agent benzotriazole. The treated copper powder raw materials were used in the ratios shown in Table 1, and a mixture of 70% by weight of the copper powder raw material and 30% by weight of the graphite powder was applied at room temperature under a pressing pressure of 2.5 t / cm 2 . It was pressed and sintered at 600 ° C. to obtain a molded body for an electric brush (a rectangular parallelepiped having a thickness of about 6 mm, a width of about 12 mm and a length of about 30 mm).
【００１３】上記の成形体を用い、アムスラー型材料試
験機を用い、支点間距離２５ｍｍの条件下で曲げ強さ
（Ｋｇ／ｃｍ2 ）を測定した。同一の製造条件で製造し
た５個の試料について測定し、その平均値を求めた。ま
た、上記の成形体を温度８０℃、湿度９０％の促進条件
下、２４０時間での重量増加（％）を求め、また酸化に
起因する外観の変化を観察した（耐酸化性）。それらの
結果を表１に示す。The bending strength (Kg / cm 2 ) was measured using the above-mentioned molded product and using an Amsler type material testing machine under the condition that the distance between fulcrums was 25 mm. Five samples manufactured under the same manufacturing conditions were measured, and the average value was calculated. Further, the weight increase (%) of the above-mentioned molded product at 240 hours under accelerated conditions of temperature 80 ° C. and humidity 90% was determined, and a change in appearance due to oxidation was observed (oxidation resistance). The results are shown in Table 1.
【００１４】[0014]
【表１】 [Table 1]
【００１５】[0015]
【発明の効果】本発明により、従来の電解銅粉を用いて
得た電刷子と比較して、抵抗率及び耐酸化性がほとんど
損なわれていないが、強度、特に曲げ強さが著しく増大
されている電刷子が得られる。EFFECTS OF THE INVENTION According to the present invention, the resistance and the oxidation resistance are hardly impaired, but the strength, especially the bending strength is remarkably increased, as compared with the electric brush obtained by using the conventional electrolytic copper powder. You can get the electric brush.
Claims (4)
１５μｍ以下である極微細銅粉４〜２０重量％とからな
る銅粉原料及び黒鉛原料を用いることを特徴とする電刷
子の製造方法。1. An electric brush using a copper powder raw material and a graphite raw material comprising 96 to 80% by weight of electrolytic copper powder and 4 to 20% by weight of ultrafine copper powder having an average particle size of 15 μm or less. Production method.
ある請求項１記載の製造方法。2. The manufacturing method according to claim 1, wherein the ultrafine copper powder has an average particle diameter of 12 μm or less.
１５μｍ以下である銅粉４〜２０重量％とからなること
を特徴とする電刷子製造用銅粉原料。3. A copper powder raw material for producing an electric brush, comprising 96 to 80% by weight of electrolytic copper powder and 4 to 20% by weight of copper powder having an average particle size of 15 μm or less.
ある請求項３記載の銅粉原料。4. The copper powder raw material according to claim 3, wherein the ultrafine copper powder has an average particle diameter of 12 μm or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4021587A JPH05190240A (en) | 1992-01-13 | 1992-01-13 | Manufacture of electric brush and copper powder material for manufacturing electric brush |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4021587A JPH05190240A (en) | 1992-01-13 | 1992-01-13 | Manufacture of electric brush and copper powder material for manufacturing electric brush |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH05190240A true JPH05190240A (en) | 1993-07-30 |
Family
ID=12059174
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4021587A Pending JPH05190240A (en) | 1992-01-13 | 1992-01-13 | Manufacture of electric brush and copper powder material for manufacturing electric brush |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH05190240A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0644097A1 (en) * | 1993-09-16 | 1995-03-22 | RISOMESA S.p.A. | A current return assembly for railway traction and brushes therefor |
| US6132487A (en) * | 1998-11-11 | 2000-10-17 | Nikko Materials Company, Limited | Mixed powder for powder metallurgy, sintered compact of powder metallurgy, and methods for the manufacturing thereof |
| CN103862030A (en) * | 2012-12-18 | 2014-06-18 | 重庆华浩冶炼有限公司 | Copper powder composition and preparation method thereof |
| JP2021009788A (en) * | 2019-07-01 | 2021-01-28 | 日本製鉄株式会社 | Metal graphite brush |
-
1992
- 1992-01-13 JP JP4021587A patent/JPH05190240A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0644097A1 (en) * | 1993-09-16 | 1995-03-22 | RISOMESA S.p.A. | A current return assembly for railway traction and brushes therefor |
| US6132487A (en) * | 1998-11-11 | 2000-10-17 | Nikko Materials Company, Limited | Mixed powder for powder metallurgy, sintered compact of powder metallurgy, and methods for the manufacturing thereof |
| CN103862030A (en) * | 2012-12-18 | 2014-06-18 | 重庆华浩冶炼有限公司 | Copper powder composition and preparation method thereof |
| CN103862030B (en) * | 2012-12-18 | 2017-10-27 | 重庆有研重冶新材料有限公司 | A kind of copper powder composition |
| JP2021009788A (en) * | 2019-07-01 | 2021-01-28 | 日本製鉄株式会社 | Metal graphite brush |
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