Abstract: A roller for rolling mill comprising an entirely non-metallic sintered body composed principally of at least one material selected from silicon carbide, silicon nitride, sialon, alumina and zirconia and having a relative density which is at least 96% of the theoretical density, the roller having an initial crown in the range of -300 .mu.m to +300 .mu.m, is provided. This roller for rolling mill has a high hardness and high wear resistance and can be used as a work roll.

Abstract: A roller for rolling mill comprising an entirely non-metallic sintered body composed principally of at least one material selected from silicon carbide, silicon nitride, sialon, alumina and zirconia and having a relative density which is at least 96% of the theoretical density of the sintered body, the roller having an initial crown in the range of -300 .mu.m to +300 .mu.m, is provided. This roller for rolling mill has a high hardness and high wear resistance and can be used as a work roll.

Abstract: In a process for producing a zirconium-based alloy in which after the zirconium-based alloy is subjected to hot plastic working, it is subjected to cold plastic working and then to annealing and these steps are repeated at least twice, the present invention provides a process for producing a zirconium-based alloy characterized in that after the alloy is subjected to solid solution treatment in which it is heated to a temperature within the range including the .alpha. phase and the .beta. phase of the alloy, or within the range of the .beta. phase and is then quenched, cold plastic working is effected at least twice.

Abstract: In a process for producing a zirconium-based alloy in which after the zirconium-based alloy is subjected to hot plastic working, it is subjected to cold plastic working and then to annealing and these steps are repeated at least twice, the present invention provides a process for producing a zirconium-based alloy characterized in that after the alloy is subjected to solid solution treatment in which it is heated to a temperature within the range including the .alpha. phase and the .beta. phase of the alloy, or within the range of the .beta. phase and is then quenched, cold plastic working is effected at least twice.

Abstract: A zirconium alloy having superior corrosion resistance, containing Sn of a small amount not less than the amount of Sn existing in the solid-solution of the zirconium alloy at a room temperature, and at least one kind of Fe and Cr each of a small amount not less than the amount of each of Fe and Cr existing in the solid-solution of the zirconium alloy at a room temperature,the zirconium alloy being annealed after the solution heat treatment at a temperature at which both the .alpha. phase and .beta. phase thereof are included in the zirconium alloy,the total amount of said at least one kind of Fe and Cr existing in the solid-solution of the zirconium alloy being not less than 0.26%.

Abstract: A small-sized, light weighted vacuum circuit interrupter is provided. The interrupter comprises a vacuum container confining a vacuum atmosphere of a pressure less than 10.sup.-5 mmHg and a pair of electrodes at least one of which is a movable electrode for making and breaking an electric circuit including either a transformer of a rated surge voltage strength of less than 45 kV or a motor of a rated surge voltage strength of less than 25 kV. At least one of the electrodes has a contact made of a porous body of a refractory conductive material and an impregnate selected from the group consisting of silver telluride, silver selenide and mixtures thereof impregnated in the porous body in an amount sufficient to give the interrupter a chopping current of not more than 1A and an arc extinguishing capability at 1MHz of not more than 27 A/.mu.s when measured in a circuit of 6 kV.

Abstract: A vacuum circuit breaker comprising a vacuum vessel and a pair of electrodes disposed in the vessel, which is superior in chopping current characteristic, at least a contact of at least one of the electrodes being made of a member having a skeleton of an iron group element, pores in which skeleton are impregnated with at least one kind selected from a group consisting of silver; an alloy of Ag and at least one of Te, Se, Bi, Pb, Tl, In, Cd, Sn and Sb; and the intermetallic compound of Ag, the breaker having rated voltage of 3.6 to 36 KV and rated breaking currents of 8 to 60 KA.

Abstract: A ceramic substrate with metal plate, wherein a metal plate consisting mainly of copper is bonded to a ceramic substrate through a brazing layer consisting of a mixture of copper oxide and copper.

Abstract: Herein disclosed is a stacked or laminated structure which is rigidly integrated by sandwiching a metal layer between a first matrix-fiber composite layer prepared to have as a whole a thermal expansion coefficient and a second matrix-fiber layer prepared to have as a whole another thermal expansion coefficient different from that of the first matrix-fiber composite layer. The intervening metal layer acts as a buffer for the first and second matrix-fiber composite layers. The stacked structure according to the present invention can by used as the chip carrier of a semiconductor device, for example.

Abstract: A method of production of a composite billet for a nuclear fuel cladding tube wherein a hollow inner billet of zirconium is inserted in a hollow outer billet of a nuclear fuel cladding material. Following insertion of a resilient member in the hollow inner billet, pressure is applied to the resilient member axially of the billets to force the inner billet against the outer billet, to produce a pressure bonding between an inner surface of the outer billet and an outer surface of the inner billet.

Abstract: A semiconductor device includes a semiconductor substrate having electrodes brazed thereto. The electrode is made of a Cu-C composite material in which carbon fibers are embedded in copper matrix. The carbon fibers are so disposed as to be in a ring-like shape or a loop shape substantially in parallel with a surface of the semiconductor substrate onto which the electrode is brazed. The carbon fibers disposed in an outer peripheral portion have a higher longitudinal elastic modulus than that of the carbon fibers positioned at a central portion of the electrode. The electrode thus has a thermal expansion coefficient approximating to that of the semiconductor substrate. Content of copper can be increased at the central portion of the electrode for attaining a high thermal conductivity.

Abstract: An electrode of a vacuum circuit breaker, having a high dielectric strength, large breaking current and superior non-welding characteristic. The electrode is made of a cast alloy comprising copper, 20 wt% or less of rare earth metal such as lanthanum, cerium or an alloy of either one of these rare earth metal with another rare earth metal, 10 wt% or less of a metal such as lead and bismuth having a lower melting point and a higher vapor pressure than copper, and 0.1 to 30 wt% of a metal of iron group. A part of the rare earth metal and a part of the metal having the lower melting point and higher vapor pressure than copper are crystallized in the grain boundary and in the grains of copper.

Abstract: A bundle of carbon fibers each coated with copper or copper alloy is uniformly wound around a core rod under tension, and subjected to a hot press treatment in a non-oxidizing atmosphere. The core rod is then cut off along the surface of a plate formed by the hot-press to form a supporting electrode plate for a semiconductor device. The electrode plate thus fabricated incorporates therein carbon fibers in a spiral and concentric circular array around the core rod.

Abstract: A light source is disclosed which can be used in atomic absorption analysis using the Zeeman effect. In operation, an external magnetic field is applied to the hollow cathode of the light source to cause the Zeeman-splitting of an emission line from the cathode material. The hollow cathode is made of a ferromagnetic metal as which is the element of interest for analysis and a metal for reducing the magnetic shield of the externally applied magnetic field by the ferromagnetic metal so that the external magnetic field effectively acts on the hollow portion of the cathode to provide the desired Zeeman-splitting. The hollow cathode is designed such that the product of the saturation flux densities of the cathode materials and the volume thereof is equal to or smaller than 0.2(Wb.multidot.m).times.10.sup.-6. The emission line from the cathode material is produced by excitation from a high frequency power supply, the power supply being connected to the cathode and the anode of the light source.

Abstract: A method of producing a vacuum circuit breaker, the breaker contacts of which are made of a cast alloy which contains copper or a copper alloy as its main component and, as the sub-component, a metal having a lower melting point and a higher vapor pressure than the main component and having a solubility limit to the main component at room temperature, e.g. lead, bismuth or an alloy of lead and bismuth, the sub-component being contained in excess of said solubility limit. The cast alloy is heated at a temperature not lower than 800.degree. C. but not so high as to cause a melting of the cast alloy, in a vacuum atmosphere which ranges in a pressure between 10.sup.-4 and 10.sup.-6 Torr, before the alloy is mounted as the breaker contacts in the vacuum circuit breaker. A plastic working may be imparted to the cast alloy before the mounting, by, for example, forging.

Abstract: A vacuum-type circuit breaker comprising an evacuated container, and a pair of contacts disposed in the container and adapted to be moved between an open position and a closed position to permit a circuit breaking arc to be generated across the contacts, the contacts being made of a copper alloy containing manganese. The vacuum-type circuit breaker provided with the contacts of the aforementioned type has a higher dielectric strength than conventional vacuum-type circuit breakers.

Abstract: A composite joint system is disclosed in which a composite structure containing carbon fibers embedded in a copper matrix in any configuration, e.g. in one direction, in random directions, in mesh form, spirally or radially is joined to another structure through a brazing material such as solder, Al brazer or Ag brazer. A film of metal such as Ni, Cr, Mo, W, Ta, Ti, Zr, V, an alloy of one or some of such metals, or the combination of some thereof is interposed between the composite structure and the brazing material. The metal film has a good wettability to both the composite structure material and the brazing material.

Abstract: A semiconductor device comprises a semiconductor substrate and at least one supporting electrode soldered to one surface of the semiconductor substrate. The supporting electrode is constituted by a composite body having fibers embedded in a matrix of an electrically conductive metal. The coefficient of the thermal expansion of the fibers is substantially equal to or smaller than that of the semiconductor substrate. The fiber is arrayed in an annular, circular, spiral or the like pattern at least in the surface portion of the composite body on which the composite body is bonded to the substrate.

Abstract: In a vacuum-type circuit breaker, a contact is composed of a principal component material of Cu alloy, to which a Pb-Bi alloy, containing either 18 to 45 weight % Bi or 65 to 80 weight % Bi and at least one of either cobalt or iron are added. Said contact is provided with a structure in which at least one of either cobalt phase or iron phase is dispersed in a copper matrix and Pb-Bi alloy phase is dispersed in the grain boundary, and has extremely low chopping current.

Abstract: Copper powder, carbon fibers arranged in random directions and a metal capable of reacting with carbon fibers are homogeneously mixed together, and the mixture is heated and molded under high pressure to form an integral composite. The so formed carbon fiber-copper matrix composite has no directional characteristic in mechanical properties, and the linear thermal expansion coefficient of the composite is low and the thermal stability of the composite is so high that when it is exposed to high temperature, no damage by thermal deformation is caused.