【発明の詳細な説明】[Detailed description of the invention]
本発明は銅−窒化物系の封入用電気接点材料に
係る。従来、封入用電気接点材料としては、銀系
合金、金系合金、パラジウム系合金などの貴金属
系例えば銀−酸化カドミウム12重量％より成る複
合電気接点材料が小電流乃至中電流域で優れた接
点特性を示すものとして各方面で広く用いられて
きた。然し乍ら、近時電気機器及び電子機器の小
型化により電気接点材料に要求される接点特性が
苛酷になつてきており、従来の銀−酸化カドミウ
ム系の複合電気接点材料では耐溶着性に劣り、使
用に耐えなくなつてきた。この為更に耐溶着性に
優れた封入用電気接点材料が要望されている。
一方貴金属の使用をおさえ安価な接点材料を供
給する為に電気電導度が銀についで大きく銀より
融点の高い銅に着目し、これを母合金とする接点
材料を使用しようとする試みがなされはじめた。
銅を接点材料として使用する場合銅の耐蝕性が問
題となるが、この問題は銅を真空中あるいは中性
ガス中で使用することにより解決され貴金属を母
合金として用いた場合に比較して何ら遜色のない
特性を示すものである。特に窒化物は融点の高い
材料が多くこれらの高融点材料を銅の分散強化材
として使用した場合、消耗量が小さくまた、溶着
力についても優れた特性を示すことが期待され
る。
本発明は上記諸事項に鑑みなされたものであり
従来の銀−酸化物系の複合電気接点材料よりも優
れた接点性能、とりわけ優れた消耗特性及び耐溶
着性を有する複合電気接点材料を提供せんとする
ものである。
本発明の封入用電気接点材料は銅中に室化亜鉛
0.6〜20重量％を添加して成るものである。銅中
に窒化亜鉛を添加した理由は窒化亜鉛が空気中で
なければ熱に対して安定であり、苛酷な条件で使
用される接点を強化する充分な性質を有するから
である。
本発明の電気接点材料に於いて、銅中に添加す
る窒化亜鉛を0.6〜20重量％としたのは、0.6重量
％以下では銅の地が充分に強化されない為に耐消
耗特性、あるいは耐溶着特性に関しては良好な結
果は得られない。また20重量％以上の組成では加
工が困難となり、材料の導電率も低くなるので良
好な結果は得られない。以上の理由により特許請
求の範囲に記載した組成を限定したものである。
なおこれらの銅−窒化物材料を窒素雰囲気中で
使用した場合さらにすぐれた耐溶着特性を示すも
のである。
実施例
平均粒径4μの銅粉と、重量比で１％、10％、
18％の窒化亜鉛粉を加えた３種をそれぞれＶ型混
合器により３時間混合した後粉末をルツボに充て
んし所定の密度に達するまで焼結圧縮を繰り返し
た材料を熱間で押出した。これを伸線機により線
材とした後、ヘツダー機により加工し下表の組成
を有する頭部径4φmm、頭高1.1mm、脚部径2.8φmm、
脚長1.6mmのリベツト型接点を得た。
従来例
銀−カドミウム合金を鋳造後引ぬき伸線加工を
行ないこれをヘツダー機により頭部径4φmm、頭
高1.1mm、脚部径2.8φmm、脚長1.6mmのリベツト形
状に成形した後５気圧800℃で内部酸化を行ない
銀酸化カドミウム12重量％とした。
然して上記実施例、従来例の電気接点を下記の
試験条件にて開閉試験を行い、溶着発生までの開
閉回数を測定し且つ接触抵抗、消耗を測定したと
ころ、下記の表の右欄に示すような結果を得た。
試験条件
電圧 A.C.100V50Hz
電流 投入電流40A、定常電流 10A
開閉頻度 20回／分
負荷 抵抗
開閉回数 溶着発生まで
雰囲気 窒素雰囲気
The present invention relates to a copper-nitride based electrical contact material for encapsulation. Conventionally, as electrical contact materials for encapsulation, noble metals such as silver alloys, gold alloys, and palladium alloys, for example, composite electrical contact materials made of 12% by weight of silver and cadmium oxide, have been used as contacts that are excellent in the small to medium current range. It has been widely used in various fields to indicate characteristics. However, with the recent miniaturization of electrical and electronic devices, the contact characteristics required of electrical contact materials have become more severe, and conventional silver-cadmium oxide composite electrical contact materials have poor welding resistance and are no longer used. I've become unable to bear it. For this reason, there is a need for an electrical contact material for encapsulation that has even better welding resistance. On the other hand, in order to reduce the use of precious metals and provide inexpensive contact materials, attention has been focused on copper, which has the second highest electrical conductivity after silver and a higher melting point than silver, and attempts have begun to use copper as a mother alloy for contact materials. Ta.
When copper is used as a contact material, corrosion resistance of copper becomes a problem, but this problem is solved by using copper in a vacuum or neutral gas, and it is no more expensive than using precious metals as the mother alloy. It shows comparable characteristics. In particular, many nitrides have high melting points, and when these high melting point materials are used as dispersion reinforcing materials for copper, they are expected to exhibit small consumption and excellent welding strength. The present invention has been made in view of the above-mentioned matters, and it is an object of the present invention to provide a composite electrical contact material that has superior contact performance, especially superior wear characteristics and welding resistance, than conventional silver-oxide composite electrical contact materials. That is. The electrical contact material for encapsulation of the present invention contains zinc chloride in copper.
It is made by adding 0.6 to 20% by weight. The reason for adding zinc nitride to the copper is that zinc nitride is thermally stable except in air and has sufficient properties to strengthen contacts used in harsh conditions. In the electrical contact material of the present invention, the reason why the zinc nitride added to the copper is 0.6 to 20% by weight is that if it is less than 0.6% by weight, the copper base will not be sufficiently strengthened, so the wear resistance or welding resistance can be improved. Good results cannot be obtained regarding properties. Furthermore, if the composition is more than 20% by weight, processing becomes difficult and the conductivity of the material becomes low, making it difficult to obtain good results. For the above reasons, the compositions described in the claims are limited. Furthermore, when these copper-nitride materials are used in a nitrogen atmosphere, they exhibit even better anti-welding properties. Example Copper powder with an average particle size of 4μ and 1%, 10% by weight,
After mixing each of the three types with 18% zinc nitride powder in a V-type mixer for 3 hours, the powders were filled into a crucible and sintered and compressed repeatedly until a predetermined density was reached, and the material was hot extruded. This is made into a wire rod using a wire drawing machine, and then processed using a header machine to create a wire with a head diameter of 4φmm, a head height of 1.1mm, and a leg diameter of 2.8φmm, which have the composition shown in the table below.
A rivet type contact with a leg length of 1.6 mm was obtained. Conventional example: After casting a silver-cadmium alloy, it was drawn and wire-drawn, and then formed into a rivet shape with a head diameter of 4φmm, head height of 1.1mm, leg diameter of 2.8φmm, and leg length of 1.6mm using a header machine, and then heated to 5 atm 800 Internal oxidation was carried out at ℃ to give 12% by weight of silver cadmium oxide. However, the electrical contacts of the above example and conventional example were subjected to opening/closing tests under the following test conditions, and the number of openings and closings until welding occurred was measured, as well as contact resistance and wear. As a result, as shown in the right column of the table below. I got good results. Test conditions Voltage AC100V50Hz Current Supply current 40A, steady current 10A Switching frequency 20 times/min load Resistance switching number of times Atmosphere until welding occurs Nitrogen atmosphere
【表】【table】
【表】
上記の表の右欄の数値で明らかなように実施例
の電気接点材料にて作つた電気接点は、従来例の
電気接点材料に比し窒化亜鉛の添加量の少ない実
施例１では低い接触抵抗を示し、添加量の多い実
施例２では優れた耐溶着性を示していることがわ
かる。また実施例２では従来例の電気接点材料に
比し耐消耗性、耐溶着性が優るとも劣らずかつ安
定した低接触抵抗を示すことがわかる。
以上詳記した通り本発明による複合電気接点材
料は、従来の銀−酸化カドミウム電気接点材料に
較べ耐溶着性、耐消耗性に優れた性能を示すので
最近の電気及び電子機器の小型化に伴なう苛酷な
使用条件にも対応できる接点性能を備えた画期的
な封入用電気接点材料と言える。[Table] As is clear from the values in the right column of the table above, the electrical contacts made with the electrical contact material of Example 1 had a smaller amount of added zinc nitride than the electrical contact material of the conventional example. It can be seen that Example 2, which exhibits low contact resistance and has a large addition amount, exhibits excellent welding resistance. Furthermore, it can be seen that Example 2 exhibits excellent wear resistance and welding resistance as well as stable low contact resistance compared to the conventional electrical contact materials. As detailed above, the composite electrical contact material according to the present invention exhibits superior performance in welding resistance and abrasion resistance compared to conventional silver-cadmium oxide electrical contact materials, and is therefore used in conjunction with the recent miniaturization of electrical and electronic equipment. It can be said to be an innovative electrical contact material for encapsulation with contact performance that can withstand even the harshest operating conditions.