JPH0425681B2

JPH0425681B2 -

Info

Publication number: JPH0425681B2
Application number: JP57226207A
Authority: JP
Inventors: Hideyuki Kanai; Takashi Takahashi; Motomasa Imai; Osamu Furukawa
Original assignee: Tokyo Shibaura Electric Co Ltd
Current assignee: Toshiba Corp
Priority date: 1982-12-24
Filing date: 1982-12-24
Publication date: 1992-05-01
Also published as: JPS59117202A

Description

[Detailed description of the invention]

［発明の技術分野］本発明は酸化亜鉛（ZnO）を主成分とする焼結
体からなる電圧電流非直線抵抗体に関する。［発明の技術的背景とその問題点］従来から各種の電圧電流非直線抵抗体が研究さ
れているが、その中の一つにZnOを主成分とした
焼結体を用いたものがある。このZnOを主成分と
した焼結体を用いたものにおいては、各種副成分
が添加されて所望の特性を得ることが試みられて
いる。このような電圧電流非直線抵抗体に要求さ
れる特性としては、電圧電流非直線特性、寿命特
性等があるが、いずれにも優れた特性を有するも
のを得るのは困難なことである。例えば特開昭49
−119188号に示されているように、ZnOを主成分
としBi₂O₃、CoO、Sb₂O₃、NiO、MnOを副成分
として添加した電圧電流非直線抵抗体があるが、
この場合も電圧電流非直線特性において十分な特
性は得られていない。また特公昭56−33842号に示されているように、
ZnOを主成分とし酸化硼素を含むガラスを添加し
て焼結することにより、直流通電において制限電
圧の低下しない電圧電流非直線抵抗体を得ること
が試みられている。しかしながらこのような電圧
電流非直線抵抗体においても、電圧電流非直線特
性、寿命特性ともにすぐれたものは得られていな
い。特に避雷器等の大きなサージ吸収を目的とす
る場合は特に電圧電流非直線特性、寿命特性に優
れたものが要求される。［発明の目的］本発明は電圧電流非直線特性、寿命特性ともに
優れた電圧電流非直線抵抗体を提供することを目
的とする。［発明の概要］本発明は酸化亜鉛を主成分とし、副成分として
ビスマス、コバルト、マンガン、アンチモン、ニ
ツケル、アルミニウムがそれぞれBi₂O₃、Co₂O₃、
MnO、Sb₂O₃、NiO、Al³⁺に換算して、 Bi₂O₃ 0.1〜5mol％、 Co₂O₃ 0.1〜5mol％、 MnO 0.1〜5mol％、 Sb₂O₃ 0.1〜5mol％、 NiO 0.1〜5mol％、 Al³⁺ 0.001〜0.05mol％含有され；かつこの組成に対してAg₂O、SiO₂の
うち少なくとも一種がそれぞれ0.002〜0.2wt％、
0.001〜0.1wt％含有された焼結体からなることを
特徴とする電圧電流非直線抵抗体である。上記組成をとることにより、電圧電流非直線特
性、寿命特性ともに向上する。Bi₂O₃、Co₂O₃、
MnO、Sb₂O₃、NiOをそれぞれ0.1〜5mol％とし
たのは、この範囲をはずれると、非直線特性、寿
命特性が劣化してしまうからである。またAl3＋
を0.001〜0.05mol％としたのは、この範囲をはず
れると、非直線特性、寿命特性特に非直線特性が
大幅に劣化してしまうからである。またAg₂O、SiO₂をそれぞれ0.002〜0.2wt％、
0.001〜0.1wt％としたのは、この範囲より少ない
含有量だと、寿命特性を改善する効果があらわれ
ず、この範囲を越えてしまうと、寿命特性を改善
する効果がほとんどあらわれず、かえつて非直線
性をも劣化させてしまうからである。またこの
Ag₂O、SiO₂はそれぞれ単独で加えても寿命改善
の効果はあるが、単独よりは２種加えた方がより
一層の効果を得ることができる。さらに本発明では、前述したようなAg₂O、
SiO₂に加えて0.002〜0.2wt％のB₂O₃を含有する
ことにより、一層寿命特性を改善することが可能
である。［発明の効果］以上説明したように本発明によれば、電圧電流
非直線特性、寿命特性ともに優れた電圧電流非直
線抵抗体を得ることができる。従つて避雷器等の
大きいサージ吸収を行なう場合に用いると好適で
ある。［発明の実施例］以下本発明の実施例を説明する。 ZnOに副成分としてBi₂O₃、Co₂O₃、MnO、
Sb₂O₃、NiO、Al（NO₃）₃・9H₂O、Ag₂O、SiO₂、
B₂O₃を所望の組成比で調合・混合の後、バイン
ダーとしてPVAを加え造粒し、円板状の板材に
成形した。この板材を乾燥した後1100〜1300℃
2hr程度の焼成の後両面研磨を施して、直径20mm
厚さ２mmの焼結体を形成した。この試料の両面にAl溶射により電極を設け電
圧電流非直線抵抗体を形成し各種特性を測定し
た。この結果を第１表に示す。第１表には各組成
分で本発明の範囲外のものについても比較例とし
て示した。第１表において、電圧電流非直線特性
はV_1KA／V₁m_A、寿命特性はL₂₀₀で示す。 V_1KA／V₁m_A＝Ｖ（1KA電流通電時の電圧）／Ｖ（１ｍＡ
電流通電時の電圧） L₂₀₀＝Ｖ（200hr後）−Ｖ（初期）／Ｖ（初期）×100 〔L₂₀₀中の電圧は１ｍＡ通電時の50Hz正弦波波高
値であり、Ｖ（200hr後）はV₁m_Aの95％の電圧を
周囲温度150℃で200時間印加後、室温で測定した
値である。〕 [Technical Field of the Invention] The present invention relates to a voltage-current nonlinear resistor made of a sintered body containing zinc oxide (ZnO) as a main component. [Technical background of the invention and its problems] Various types of voltage-current nonlinear resistors have been studied in the past, and one of them uses a sintered body containing ZnO as a main component. In products using this sintered body mainly composed of ZnO, attempts have been made to add various subcomponents to obtain desired characteristics. The characteristics required of such a voltage-current non-linear resistor include voltage-current non-linear characteristics, life-span characteristics, etc., but it is difficult to obtain one that has excellent characteristics in all of them. For example, JP-A-49
As shown in No. 119188, there is a voltage/current nonlinear resistor that has ZnO as its main component and Bi ₂ O ₃ , CoO, Sb ₂ O ₃ , NiO, and MnO are added as subcomponents.
In this case as well, sufficient voltage-current nonlinear characteristics are not obtained. Also, as shown in Special Publication No. 56-33842,
Attempts have been made to obtain a voltage-current nonlinear resistor whose limiting voltage does not drop under direct current flow by adding and sintering a glass containing ZnO as a main component and boron oxide. However, even in such voltage-current non-linear resistors, excellent voltage-current non-linear characteristics and life characteristics have not been obtained. In particular, when the purpose is to absorb large surges such as in lightning arresters, a material with excellent voltage-current nonlinear characteristics and life characteristics is required. [Object of the Invention] An object of the present invention is to provide a voltage-current nonlinear resistor that is excellent in both voltage-current nonlinear characteristics and life characteristics. [Summary of the invention] The present invention has zinc oxide as the main component, and bismuth, cobalt, manganese, antimony, nickel, and aluminum as subcomponents, respectively Bi ₂ O ₃ , Co ₂ O ₃ ,
In terms of MnO, Sb ₂ O ₃ , NiO, Al ³⁺ , Bi ₂ O ₃ 0.1-5 mol%, Co ₂ O ₃ 0.1-5 mol%, MnO 0.1-5 mol%, Sb ₂ O ₃ 0.1-5 mol%, Contains 0.1 to 5 mol% of NiO, 0.001 to 0.05 mol% of Al ³⁺ ; and 0.002 to 0.2 wt% of at least one of Ag ₂ O and SiO ₂ to this composition, respectively.
This is a voltage/current nonlinear resistor characterized by being made of a sintered body containing 0.001 to 0.1 wt%. By adopting the above composition, both voltage-current nonlinear characteristics and life characteristics are improved. _Bi2O3 _, _Co2O3 _,
The reason why MnO, Sb ₂ O ₃ , and NiO are each set at 0.1 to 5 mol % is because outside this range, nonlinear characteristics and life characteristics deteriorate. Also Al3+
The reason why is set to 0.001 to 0.05 mol % is because if it deviates from this range, nonlinear characteristics, life characteristics, especially nonlinear characteristics will deteriorate significantly. In addition, Ag ₂ O and SiO ₂ were added at 0.002 to 0.2 wt%, respectively.
The reason for setting it at 0.001 to 0.1wt% is that if the content is less than this range, the effect of improving the life characteristics will not appear, and if it exceeds this range, the effect of improving the life characteristics will hardly appear, and on the contrary, the effect of improving the life characteristics will not appear. This is because nonlinearity is also deteriorated. Also this
Although Ag ₂ O and SiO ₂ have the effect of improving the life span even if they are added alone, the effect can be obtained even more when two types are added than when they are added alone. Furthermore, in the present invention, Ag ₂ O as described above,
By containing 0.002 to 0.2 wt% of B ₂ O ₃ in addition to SiO ₂ , it is possible to further improve the life characteristics. [Effects of the Invention] As explained above, according to the present invention, a voltage-current nonlinear resistor having excellent both voltage-current nonlinear characteristics and life characteristics can be obtained. Therefore, it is suitable for use in cases where large surge absorption is required, such as in lightning arresters. [Embodiments of the Invention] Examples of the present invention will be described below. Bi ₂ O ₃ , Co ₂ O ₃ , MnO,
Sb ₂ O ₃ , NiO, Al(NO ₃ ) ₃・9H ₂ O, Ag ₂ O, SiO ₂ ,
After preparing and mixing B ₂ O ₃ in a desired composition ratio, PVA was added as a binder and granulated, and the mixture was formed into a disc-shaped plate. After drying this plate material, the temperature is 1100~1300℃.
After baking for about 2 hours, both sides are polished and the diameter is 20mm.
A sintered body with a thickness of 2 mm was formed. Electrodes were provided on both sides of this sample by Al spraying to form a voltage-current nonlinear resistor, and various characteristics were measured. The results are shown in Table 1. In Table 1, compositions outside the scope of the present invention are also shown as comparative examples. In Table 1, the voltage-current nonlinear characteristics are expressed as V _1KA /V ₁ _mA , and the life characteristics are expressed as L ₂₀₀ . V _1KA /V ₁ m _A =V (voltage when 1KA current is applied) /V (1mA
Voltage when current is applied) L ₂₀₀ = V (after 200 hours) - V (initial) / V (initial) x 100 [The voltage in L ₂₀₀ is the peak value of a 50Hz sine wave when 1 mA is applied, and V (after 200 hours) is the value measured at room temperature after applying a voltage of 95% of V ₁ _mA for 200 hours at an ambient temperature of 150°C. ]

【表】【table】

【表】第１表から明らかなように、本発明の実施例１
〜69においては、非直線特性（V_1KA／V₁m_A）、
寿命特性（L₂₀₀）ともに、比較例１〜15に比べ優
れていることがわかる。実施例１〜６はAg₂O、SiO₂のうち少なくとも
一種を含有するもの、実施例７〜69はさらに
0.002〜0.2wt％のB₂O₃を含有するものである。第
１表から明らかなように、Ag₂O、SiO₂の１種を
含有するものより２種を含有するものの方が寿命
特性が良く、さらに0.002〜0.2wt％のB₂O₃を添加
すれば、一層寿命特性が向上している。しかしな
がら比較例13〜14からわかるように含有量が多く
なつてしまうと、寿命特性を改善する効果があら
われないばかりか、非直線性をも悪くしてしま
う。[Table] As is clear from Table 1, Example 1 of the present invention
~69, the nonlinear characteristics (V _1KA /V ₁ m _A ),
It can be seen that both the life characteristics (L ₂₀₀ ) are superior to Comparative Examples 1 to 15. Examples 1 to 6 contain at least one of Ag ₂ O and SiO ₂ , and Examples 7 to 69 further contain
It contains 0.002-0.2wt _% _B2O3 . As is clear from Table 1, those containing Ag ₂ O and SiO ₂ have better life characteristics than those containing one of them, and even if 0.002 to 0.2 wt% B ₂ O ₃ is added In other words, the life characteristics are further improved. However, as can be seen from Comparative Examples 13 and 14, when the content increases, not only is the effect of improving the life characteristics not achieved, but also the nonlinearity becomes worse.

Claims

[Claims] 1 Main component is zinc oxide, and subcomponents are bismuth, cobalt, manganese, antimony, nickel, and aluminum, respectively, Bi ₂ O ₃ , Co ₂ O ₃ ,
In terms of MnO, Sb ₂ O ₃ , NiO, Al ³⁺ , Bi ₂ O ₃ 0.1-5 mol% Co ₂ O ₃ 0.1-5 mol% MnO 0.1-5 mol% Sb ₂ O ₃ 0.1-5 mol% NiO 0.1-5 mol % Al ³⁺ 0.001 to 0.05 mol%, and based on this basic composition, Ag ₂ O,
At least one of SiO ₂ is 0.002~
A voltage/current nonlinear resistor comprising a sintered body containing additives of 0.2wt% and 0.001 to 0.1wt%. 2 In claim 1, the Ag ₂ O,
_SiO2 is 0.002~0.2wt% and 0.001~0.1wt% respectively
A voltage/current nonlinear resistor characterized by containing an additive. Claim 1, characterized in that 0.002 to 0.2 wt% of B ₂ O ₃ is added to the basic composition.
The voltage/current nonlinear resistor according to item 1 or 2.