JPS6311421B2 - - Google Patents
Info
- Publication number
- JPS6311421B2 JPS6311421B2 JP26389385A JP26389385A JPS6311421B2 JP S6311421 B2 JPS6311421 B2 JP S6311421B2 JP 26389385 A JP26389385 A JP 26389385A JP 26389385 A JP26389385 A JP 26389385A JP S6311421 B2 JPS6311421 B2 JP S6311421B2
- Authority
- JP
- Japan
- Prior art keywords
- electrode
- electrode material
- weight
- discharge machining
- tungsten
- 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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- 239000007772 electrode material Substances 0.000 claims description 23
- 238000003754 machining Methods 0.000 claims description 22
- 239000011575 calcium Substances 0.000 claims description 18
- 239000010949 copper Substances 0.000 claims description 15
- 229910052709 silver Inorganic materials 0.000 claims description 13
- 239000000843 powder Substances 0.000 claims description 12
- 229910052802 copper Inorganic materials 0.000 claims description 11
- 239000004332 silver Substances 0.000 claims description 10
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 claims description 10
- 229910052721 tungsten Inorganic materials 0.000 claims description 10
- 238000004519 manufacturing process Methods 0.000 claims description 9
- 229910052791 calcium Inorganic materials 0.000 claims description 8
- 239000010937 tungsten Substances 0.000 claims description 8
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims description 7
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 7
- 238000000034 method Methods 0.000 claims description 7
- 238000005245 sintering Methods 0.000 claims description 6
- 238000002156 mixing Methods 0.000 claims description 4
- 238000000465 moulding Methods 0.000 claims description 3
- 239000002245 particle Substances 0.000 claims description 3
- 239000000463 material Substances 0.000 description 10
- 238000009760 electrical discharge machining Methods 0.000 description 6
- 239000011148 porous material Substances 0.000 description 6
- 239000002994 raw material Substances 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 239000000654 additive Substances 0.000 description 2
- 239000011230 binding agent Substances 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000005520 cutting process Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229910002804 graphite Inorganic materials 0.000 description 2
- 239000010439 graphite Substances 0.000 description 2
- 238000000227 grinding Methods 0.000 description 2
- 230000008595 infiltration Effects 0.000 description 2
- 238000001764 infiltration Methods 0.000 description 2
- 230000001590 oxidative effect Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- ZSLUVFAKFWKJRC-IGMARMGPSA-N 232Th Chemical compound [232Th] ZSLUVFAKFWKJRC-IGMARMGPSA-N 0.000 description 1
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 1
- 229910004261 CaF 2 Inorganic materials 0.000 description 1
- 229910000531 Co alloy Inorganic materials 0.000 description 1
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 229910052776 Thorium Inorganic materials 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- 238000010835 comparative analysis Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000010891 electric arc Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 239000012188 paraffin wax Substances 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 229910052712 strontium Inorganic materials 0.000 description 1
- CIOAGBVUUVVLOB-UHFFFAOYSA-N strontium atom Chemical compound [Sr] CIOAGBVUUVVLOB-UHFFFAOYSA-N 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 229910052727 yttrium Inorganic materials 0.000 description 1
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical compound [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 description 1
- 229910052726 zirconium Inorganic materials 0.000 description 1
Landscapes
- Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
- Powder Metallurgy (AREA)
Description
［発明の技術分野］
本発明は放電加工用電極材料に関し、さらに詳
しくは、加工速度が大きく、電極消耗が小さいと
同時に、電極材料自体の切削または研削加工性が
良好な放電加工用電極材料に関する。
［発明の技術的背景とその問題点］
放電加工法は、被加工物と加工電極とを絶縁性
の加工液中で極めて微小な間隙をもつて対向さ
せ、加工電極に間欠的に通電を行なうことにより
パルス性アーク放電を繰返し、被加工物を溶融も
しくは、蒸発せしめて加工する方法であり、例え
ば、超硬、ダイス鋼などに電極形状に対応した凹
部を形成する際に有用である。
かかる放電加工に使用される電極には、加工時
の自らの消耗が少ないこと、加工速度が大きいこ
とに加えて、電極自身の組織が健全で、その加工
性が優れていることが要求される。従来、放電加
工用電極材料としては、銅―タングステン、銀―
タングステンあるいはこれらにジルコニウム、チ
タン、鉄、ニツケル、ホウ素、ストロンチウム、
イツトリウム、トリウムなどを添加してなるもの
などが使用されている。これらは、いずれもタン
グステンあるいはタングステンに種々の添加物を
を配合して得られた原料粉末を成形、焼結してス
ケルトンを製造したのち、このスケルトンに銀ま
たは銀を溶浸することにより製造させることが一
般的である。
しかしながら、かかる従来の材料は、第１に材
料自身の被加工性が悪く、第２に、内部に空孔
（ポア）を有するため、この材料から製造された
電極を使用して例えば超硬材料よりなる被加工体
の底付け加工を行なうと被加工体の凹部底面に突
起が形成されてしまうなどの問題がある。また、
この材料により得られた電極の放電加工時におけ
る耐消耗性も未だ充分とは言い難く、改良の余地
が残されている。
［発明の目的］
本発明は従来のかかる問題を解消し、空孔など
のない健全な組織を有し、かつ、研削加工あるい
は切削加工などに対する被加工性に優れており、
しかも、製造された電極の放電加工時の耐消耗特
性が良好な放電加工用電極材料およびその製造方
法の提供を目的とする。
［発明の概要］
本発明者らは、上記目的を達成すべく鋭意研究
を重ねた結果、従来のCuおよび／またはAg―Ｗ
よりなる電極材料にカルシウム（Ca）を添加す
るとその被加工性が著しく向上するとともに、材
料中にポアが生ずることが少なく、しかも得られ
た電極の耐消耗特性も向上することを見出して本
発明を完成するに到つた。
すなわち、本発明の放電加工用電極材料は、カ
ルシウム0.3〜3.0重量％、銅および／または銀20
〜40重量％、および残部がタングステンよりなる
ことを特徴とし、その製造方法は、タングステン
粉末およびカルシウム粉末を混合したのち成形、
焼結して得られた焼結体に銅および／または銀を
溶浸させてなる放電加工用電極材料の製造方法で
あつて、該電極材料中、カルシウムが0.3〜3.0重
量％、銅および／または銀が20〜40重量％、残部
が実質的にタンクズテンであることを特徴とす
る。
本発明の放電加工用電極材料は、前述の如く
Ca、Ｗ、Cuおよび／またはAgの３もしくは４成
分よりなることを特徴とするものである。まず、
Caは電極材料の被加工性を向上させるとともに
空孔の発生を防止するために有効な添加成分であ
り、その配合量は0.3〜3.0重量％に設定する必要
がある。Caの添加量が0.3重量％未満の場合は充
分な添加効果が得られにくく、一方、3.0重量％
を超えると被加工性は向上するものの逆に電極の
耐消耗性が低下してしまう。好ましくは、0.8〜
２重量％である。また、Ｗ、CuおよびAgは従来
の電極材料に使用される成分であり、その配合量
はCuおよび／またはAgが20〜40重量％、Ｗが残
部にそれぞれ設定される。
かかる電極材料は次のようにして製造する。
すなわち、まず、Ca粉末とＷ粉末とを所定の
割合で混合し、しかるのち、これにバインダーを
添加して混合し、ふるい分けすることにより原料
粉を得る。このとき、Ｗの平均粒径を2.0〜10μm
とすると、CuまたはAgの溶浸処理工程におい
て、スケルトンに対するCuまたはAgのぬれ性に
不具合がなく、ポアの少ない健全な組織を実現す
ることができ、また、Caの添加がよりぬれ性を
向上させるのに効果的である。さらに、このCa
源としては、上記の如きCa単体のほかに、焼結
時にCaを生成しうるもの、例えば、CaBr2、
CaF2、CaI2、CaCO3、CaSO4、CaOなどのCa化
合物粉末を使用することもできる。ついで、この
原料粉を加圧成形して所望の形状の成形体を得た
のち、この成形体を非酸化性雰囲気中で焼結し、
ＷおよびCaよりなるスケルトンを製造する。こ
のときの焼結温度は1000〜1200℃程度とする。
しかるのち、得られたスケルトンにCuおよ
び／またはAgを溶浸させ電極材料を得る。この
溶浸工程は、例えば黒鉛容器中、1100〜1300℃に
おいて行なう。この工程終了後、電極材料に機械
加工を施すことにより所望の形状の電極とする。
［発明の実施例］
実施例１〜８、比較例１，２
Ca粉末と表示の平均粒径を有するＷ粉末を表
示の割合で混合し、このものにバインダーとして
パラフインを加えてふるい分けを行ない＃80の原
料粉を得た。この原料粉を１〜４トン／cm2で加圧
成形し、得られた成形体を非酸化性雰囲気中、
1200℃において焼結してスケルトンを製造し、こ
のスケルトンにCuおよび／またはAgを黒鉛容器
中1300℃で溶浸させ全体として表示の組成の電極
材料を得た。このものの空隙率（％）は表示した
とおりであつた。なお、空隙率は0.7％以下が望
ましい値である。ついで、このものに機械加工を
施して10×10×10mmの電極を製造し、この電極を
使用して以下のような条件で放電加工を行ない、
その加工速度（ｇ／min）および電極の重量消耗
比（％）を測定し結果を表に示した。この重量消
耗比は11.5％以下が望ましい値である。なお、表
中には電極材料の被加工性も併せて示した。但
し、被加工性については、実施例１を100として
比較評価を行ない、95以上を良好なものとする。
被加工材：超硬
加工の種類：荒加工
加工方法：底付加工
比較例 ３
スケルトンとしてＷ＋ZrO2を使用したほかは、
上記実施例と同様にして電極を製造し、同様の評
価試験を行なつて結果を表に示した。
[Technical Field of the Invention] The present invention relates to an electrode material for electrical discharge machining, and more particularly, to an electrode material for electrical discharge machining that has a high machining speed, low electrode wear, and has good cutting or grinding machinability of the electrode material itself. . [Technical background of the invention and its problems] In the electric discharge machining method, a workpiece and a machining electrode are opposed to each other with an extremely small gap in an insulating machining fluid, and the machining electrode is intermittently energized. This is a method of processing a workpiece by repeating pulsed arc discharge to melt or evaporate the workpiece, and is useful, for example, when forming a recess corresponding to the shape of an electrode in cemented carbide, die steel, etc. The electrodes used in such electric discharge machining are required to have a healthy structure and excellent machinability, in addition to low wear and tear during machining and high machining speed. . Conventionally, electrode materials for electrical discharge machining include copper, tungsten, and silver.
Tungsten or these include zirconium, titanium, iron, nickel, boron, strontium,
Products containing yttrium, thorium, etc. are used. All of these are manufactured by molding and sintering tungsten or a raw material powder obtained by blending various additives with tungsten to manufacture a skeleton, and then infiltrating this skeleton with silver or silver. This is common. However, such conventional materials firstly have poor processability and secondly, have pores inside. If the bottoming process is performed on a workpiece made of the above-mentioned materials, there are problems such as protrusions being formed on the bottom surface of the recess of the workpiece. Also,
The wear resistance of electrodes obtained using this material during electrical discharge machining is still far from satisfactory, and there is still room for improvement. [Object of the Invention] The present invention solves the conventional problems, has a healthy structure without pores, and has excellent workability for grinding or cutting.
Moreover, it is an object of the present invention to provide an electrode material for electric discharge machining, in which the manufactured electrode has good wear resistance properties during electric discharge machining, and a method for manufacturing the same. [Summary of the Invention] As a result of intensive research to achieve the above object, the present inventors discovered that the conventional Cu and/or Ag-W
The present invention was based on the discovery that when calcium (Ca) is added to an electrode material made of the following materials, its workability is significantly improved, pores are less likely to be formed in the material, and the wear resistance of the resulting electrode is also improved. I have come to complete it. That is, the electrode material for electrical discharge machining of the present invention contains 0.3 to 3.0% by weight of calcium, 20% by weight of copper and/or silver.
~40% by weight, and the balance is tungsten, and its manufacturing method involves mixing tungsten powder and calcium powder, then molding,
A method for producing an electrode material for electric discharge machining, which comprises infiltrating a sintered body obtained by sintering with copper and/or silver, the electrode material containing 0.3 to 3.0% by weight of calcium, copper and/or silver. Or, it is characterized by having 20 to 40% by weight of silver, and the remainder being substantially tank's tin. The electrode material for electric discharge machining of the present invention is as described above.
It is characterized by being composed of three or four components: Ca, W, Cu and/or Ag. first,
Ca is an effective additive component for improving the workability of the electrode material and preventing the generation of pores, and its content needs to be set at 0.3 to 3.0% by weight. If the amount of Ca added is less than 0.3% by weight, it is difficult to obtain a sufficient addition effect;
If it exceeds this, the workability improves, but the wear resistance of the electrode decreases. Preferably 0.8~
It is 2% by weight. Further, W, Cu, and Ag are components used in conventional electrode materials, and their blending amounts are set to 20 to 40% by weight for Cu and/or Ag, and the balance for W. Such an electrode material is manufactured as follows. That is, first, Ca powder and W powder are mixed at a predetermined ratio, then a binder is added thereto, mixed, and sieved to obtain raw material powder. At this time, the average particle size of W is 2.0 to 10 μm.
Therefore, in the Cu or Ag infiltration process, there is no problem in the wettability of Cu or Ag to the skeleton, and a healthy structure with few pores can be achieved, and the addition of Ca further improves the wettability. It is effective to Furthermore, this Ca
In addition to the simple Ca mentioned above, sources that can generate Ca during sintering, such as CaBr 2 ,
Ca compound powders such as CaF 2 , CaI 2 , CaCO 3 , CaSO 4 , CaO can also be used. Next, this raw material powder is pressure-molded to obtain a molded body of a desired shape, and this molded body is sintered in a non-oxidizing atmosphere.
A skeleton made of W and Ca is manufactured. The sintering temperature at this time is approximately 1000 to 1200°C. Thereafter, the obtained skeleton is infiltrated with Cu and/or Ag to obtain an electrode material. This infiltration step is carried out, for example, in a graphite container at 1100-1300°C. After this process is completed, the electrode material is machined to form the electrode into a desired shape. [Examples of the Invention] Examples 1 to 8, Comparative Examples 1 and 2 Ca powder and W powder having the indicated average particle size were mixed in the indicated ratio, paraffin was added as a binder, and sieved. Obtained 80 raw powders. This raw material powder is pressure-molded at 1 to 4 tons/cm 2 , and the resulting molded body is heated in a non-oxidizing atmosphere.
A skeleton was produced by sintering at 1200°C, and this skeleton was infiltrated with Cu and/or Ag at 1300°C in a graphite container to obtain an electrode material having the overall composition shown. The porosity (%) of this material was as indicated. Note that a desirable value for the porosity is 0.7% or less. Next, this material was machined to produce a 10 x 10 x 10 mm electrode, and this electrode was used to perform electrical discharge machining under the following conditions.
The processing speed (g/min) and weight consumption ratio (%) of the electrode were measured and the results are shown in the table. This weight consumption ratio is desirably 11.5% or less. The table also shows the processability of the electrode material. However, regarding processability, a comparative evaluation is performed with Example 1 set as 100, and a value of 95 or higher is considered good. Workpiece material: Carbide Type of machining: Rough machining Processing method: Comparative example of bottom machining 3 Except for using W+ZrO 2 as the skeleton,
Electrodes were manufactured in the same manner as in the above examples, and the same evaluation tests were conducted and the results are shown in the table.
【表】
［発明の効果］
以上の説明から明らかなように、本発明の放電
加工用電極材料は、従来の材料に比べ、ポアの含
有率が少なく健全な組織を有するとともに被加工
性に優れており、さらに、本発明の電極材料によ
り製造された放電加工用電極は、とくに、WC―
Co合金などの超硬材料よりなる被加工体の加工
時にその電極消耗が著しく低減されるため、電極
の寿命が長く、例えばかかる電極を放電加工によ
る金型の製造に適用した場合、その製造コストの
低廉化に極めて有効であり、その工業的価値は大
である。[Table] [Effects of the Invention] As is clear from the above description, the electrode material for electric discharge machining of the present invention has a healthy structure with less pore content and has excellent machinability compared to conventional materials. Furthermore, the electrode for electric discharge machining manufactured using the electrode material of the present invention is particularly suitable for WC-
Since electrode wear is significantly reduced when machining workpieces made of cemented carbide materials such as Co alloy, the life of the electrode is long and, for example, when such an electrode is applied to the manufacture of molds by electric discharge machining, the manufacturing cost is reduced. It is extremely effective in reducing the cost of production, and its industrial value is great.
Claims (1)
は銀20〜40重量％、および残部が実質的にタング
ステンよりなることを特徴とする放電加工用電極
材料。 ２ タングステン粉末およびカルシウム粉末を混
合したのち成形、焼結して得られた焼結体に銅お
よび／または銀を溶浸させてなる放電加工用電極
材料の製造方法であつて、 該電極材料中、カルシウムが0.3〜3.0重量％、
銅および／または銀が20〜40重量％、残部がタン
グステンであることを特徴とする放電加工用電極
材料の製造方法。 ３ 該タングステンの平均粒径が、２〜10μmで
ある特許請求の範囲第２項に記載の方法。[Scope of Claims] 1. An electrode material for electric discharge machining, characterized in that it contains 0.3 to 3.0% by weight of calcium, 20 to 40% by weight of copper and/or silver, and the balance essentially consists of tungsten. 2. A method for producing an electrode material for electric discharge machining, which comprises infiltrating copper and/or silver into a sintered body obtained by mixing tungsten powder and calcium powder, then molding and sintering, the electrode material comprising: , calcium 0.3-3.0% by weight,
A method for producing an electrode material for electric discharge machining, characterized in that copper and/or silver are 20 to 40% by weight, and the balance is tungsten. 3. The method according to claim 2, wherein the tungsten has an average particle size of 2 to 10 μm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26389385A JPS62127449A (en) | 1985-11-26 | 1985-11-26 | Electrode material for electric discharge machining and its production |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26389385A JPS62127449A (en) | 1985-11-26 | 1985-11-26 | Electrode material for electric discharge machining and its production |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62127449A JPS62127449A (en) | 1987-06-09 |
| JPS6311421B2 true JPS6311421B2 (en) | 1988-03-14 |
Family
ID=17395717
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP26389385A Granted JPS62127449A (en) | 1985-11-26 | 1985-11-26 | Electrode material for electric discharge machining and its production |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62127449A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004044255A1 (en) * | 2002-11-11 | 2004-05-27 | Sumitomo Electric Industries, Ltd. | Electrode material for electric discharge machining and method for production thereof |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109234597A (en) * | 2018-11-22 | 2019-01-18 | 江苏经纬阀业有限公司 | A kind of tungsten-copper alloy and preparation method thereof |
-
1985
- 1985-11-26 JP JP26389385A patent/JPS62127449A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004044255A1 (en) * | 2002-11-11 | 2004-05-27 | Sumitomo Electric Industries, Ltd. | Electrode material for electric discharge machining and method for production thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62127449A (en) | 1987-06-09 |
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