Kabushiki Kaisha Meidensha

Tsutai Suzuki

Nobuyuki Yoshioka

Yoshiyuki Kashiwagi

Hideo Koyama

Masanori Haba

A process for bonding a copper or copper-chromium alloy body and a ceramic body of components of an electrical or electronic device to each other includes a step of directly sandwiching a layer of chromium oxide between the ceramic and copper or copper-chromium bodies, a step of heating a temporary assembly of the ceramic and copper or copper-chromium alloy bodies and the layer of chromium oxide, under an atmosphere which can oxidize chromium without oxidizing copper, at a temperature of at least 900.degree. C. but below the melting point of copper or the alloy, and then a step of slowly cooling the resulting bonded assembly. In particular, in a process for bonding the alloy body to the ceramic body, the chromium oxide sandwiching step is performed concurrently with the temporary assembly heating step. The bonding process can produce a hermetic envelope, particularly a vacuum envelope of a vacuum interrupter. The process for bonding the copper or alloy body to the ceramic body of this invention is more advantageous than bonding processes employing the so-called Telefunken method, in terms of cost and steps.

Process for bonding copper or copper-chromium alloy to ceramics, and

There is provided a method of making a non-linear voltage-dependent resistor containing a ZnO element including zinc oxide as its major component by forming or coating a layer of high insulation material on the element. The layer is formed due to a vapor-solid reaction in the atmosphere of a vaporizable molecular compound containing Sb.sub.2 O.sub.3, Bi.sub.2 O.sub.4 or SiO.sub.2 at a sintering temperature. Preferably, the layer is formed due to a vapor-solid reaction in the atmosphere of a vaporization retarding compound containing ZnO, or SiO.sub.2 in addition to the vaporizable molecular compound at a sintering temperature within a sintering vessel.

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Tokyo, Japan

Tsutai Suzuki