Abstract: A new electrode is joined to a consumed electrode of the electric furnace according to a method comprising the steps of lifting and transporting the new electrode suspended from a joining apparatus by a crane, aligning both electrodes by throwing a laser beam from a projector disposed to the crane on a positioning marker disposed on a deck plate provided in the vicinity of the electric furnace, screwing a screw thread of the new electrode into a threaded hole of the consumed electrode by actuating an electric motor disposed in the joining apparatus, and tightening both electrodes at desired tightening torque by operating the motor in a stalled state with a small electric current of low frequency.

Abstract: A high-strength member of precipitation hardening martensitic steel is manufactured through the steps of heating precipitation hardening martensitic stainless steel at an austenitizing temperature, performing the first plastic working at a temperature between 200.degree. C. and 700.degree. C. so as to leave a part of austenite as retained austenite at the time of cooling the steel at Ms point or below thereafter, cooling the steel at the temperature not higher than Ms point, performing the next plastic working at a temperature not higher than As point so as to transform the retained austenite into martensite, and performing age hardening treatment at a temperature between not lower than 370.degree. C. and lower than 480.degree. C.

Abstract: An electron emitting element including a semiconductor opto-electronic layer having a split valence band and capable of emitting a beam of spin-polarized electrons from an emitting surface thereof upon incidence of an excitation laser radiation upon the emitting surface, and a reflecting mirror formed on one of opposite sides of the opto-electronic layer remote from the emitting surface and cooperating with the emitting surface to effect multiple reflection therebetween of the incident laser radiation. The emitting element may be provided with a semiconductor light modulator element for modulating the intensity of the laser radiation incident upon the opto-electronic layer. A laser source may be formed integrally with the emitting element and disposed on the side of the opto-electronic layer remote from the emitting surface.

Abstract: A levitation melting method and device through which a material having various configurations can be melted through efficient induction heating. First, a starting material(WB), whose outer diameter has been adapted to the inner diameter of a crucible(13), is inserted in crucible(13). The crucible(13) is shielded with argon gas, thereby starting the melting of the material(WB) to molten metal(WM). Subsequently, a suction tube(33) of a mold(31) is inserted into the molten metal(WM) for drawing a part of molten metal(WM) up into the mold(31) for casting. After part of the molten metal(WM) is drawn up, a sliding cover(15) is slid such that a material holder(19) is positioned right above the crucible(13). By opening a sliding plate(35) of the material holder(19), material pieces(WS) are inserted from the material holder(19) into the molten metal(WM) left in the crucible(13).

Abstract: A process of producing a highly spin-polarized electron beam, including the steps of applying a light energy to a semiconductor device comprising a first compound semiconductor layer having a first lattice constant and a second compound semiconductor layer having a second lattice constant different from the first lattice constant, the second semiconductor layer being in junction contact with the first semiconductor layer to provide a strained semiconductor heterostructure, a magnitude of mismatch between the first and second lattice constants defining an energy splitting between a heavy hole band and a light hole band in the second semiconductor layer, such that the energy splitting is greater than a thermal noise energy in the second semiconductor layer in use; and extracting the highly spin-polarized electron beam from the second semiconductor layer upon receiving the light energy.

Abstract: Molten metal melted in a levitation melting furnace is cast through a suction pipe immersed therein from above into a mold having a gas permeability in a double-structure mold chamber arranged directly above the melting furnace. The metal is levitation-melted in an inert atmosphere under atmospheric pressure. An outer mold chamber of the double-structure mold chamber is joined to the levitation melting furnace. Pressure in the outer mold chamber and in an inner mold chamber of the double-structure mold chamber and in an upper space in the levitation melting furnace is reduced to below atmospheric pressure. The suction pipe arranged in the inner mold chamber and communicating with the mold therein is immersed into the molten metal. The molten metal is cast into the mold under an increased pressure by blowing an inert gas into the upper space in the melting furnace. The inner mold chamber is raised, thereby pulling out the suction pipe from the molten metal.

Abstract: A method of producing magnetic soft ferrite of the general formula: M.sub.x Zn.sub.1-x O.Fe.sub.2 O.sub.3 (M stands for one or more of Cu, Mn, Ni, Fe, Co and Mg; and X is in the range of 0.4-0.7) by melting and casting is disclosed. Melting is carried out under controlling evaporation of Zn-component in the material of the ferrite by disposing Zn-source around the material, sealing up the melting chamber as tight as possible, or under a pressurized gas atmosphere so as to obtain the product having uniform and precise composition.

Abstract: A spring steel of medium strength and sufficient corrosion resistance prepared by simple procedures, and therefore, at a low cost, is provided. The spring steel has the alloy composition of: C 0.3-0.6%, Si 1.0-2.0%, Mn 0.1% to less than 0.5%, Cr 0.4-1.0%, V 0.1-0.3%, Ni more than 0.5% to 1.2%, Cu 0.1-0.3% and the balance of Fe, wherein S being at highest 0.005%, and [O], at highest 0.0015%. Addition of Ca 0.001-0.005% is preferable. In order to ensure clearly improved fatigue limit under corrosive environment to the conventional steel, SUP7, specific contents of S, Ni, Cr, Cu and V are chosen in the range set forth above. For the purpose of obtaining such a low hardness after normalizing at which annealing prior to processing is unnecessary contents of C, Si, Mn, Cr and Ni are further chosen in the above ranges.

Abstract: A new electrode is joined to a consumed electrode of the electric furnace according to a method comprising the steps of lifting and transporting the new electrode suspended from a joining apparatus by a crane, aligning both electrodes by throwing a laser beam from a projector disposed to the crane on a positioning marker disposed on a deck plate provided in the vicinity of the electric furnace, screwing a screw thread of the new electrode into a threaded hole of the consumed electrode by actuating an electric motor disposed in the joining apparatus, and tightening both electrodes at desired tightening torque by operating the motor in a stalled state with a small electric current of low frequency.

Abstract: Disclosed is a levitation melting crucible which can facilitate penetration of magnetism into the crucible and which can prevent a molten metal from being contaminated by an insulating material. The levatation melting crucible comprises a cylindrical main body having a closed bottom, a plurality of slits defined vertically in the circumferential wall of the main body to open inward and outward at predetermined intervals in the circumferential direction and an insulating material filled in each of the slits; wherein each slit is designed to have an inner opening width smaller than its outer opening width, with respect to the radius of the main body, for example, 1.5 A>B.

Abstract: A precipitation hardening stainless steel, which is excellent in cold workability at a solution treated state and good in proof stress after overaging treatment, consists essentially of C.ltoreq.0.010, Ni 0.010.about.0.025% (provided C+N.ltoreq.0.025%), Si.ltoreq.1.0%, Mn.ltoreq.1.2%, P.ltoreq.0.040%, S.ltoreq.0.030%, Cu: 3.0.about.5.0%, Ni: 3.0.about.4.65%, Cr: 13.0.about.16.5%, Mo.ltoreq.1.0%, Nb: (-11.43 (C+N)+0.6).about.0.5% and the balance Fe on condition that452 (C+N)+11.1 (Ni+Mn).ltoreq.73.1.

Abstract: A work 12 is selectively loaded one of forming portions 20, 22, and so on, which are formed on a mandrel 18. Then, the work 12 is pressed between the selected forming portion and a forming roll 10 and rotated together with the forming roll 10 and the mandrel 18 in this state, thereby rolled and formed a groove on its inner surface. The mandrel 18 is provided movably in its axial direction, and the forming portions 20, 22, and so on, are subsequently selected for rolling the work 12 step by step. After finishing the rolling, the work 12 is unloaded from the mandrel 18, guided by a work guiding passage, and is supplied to the sizing device 120, wherein the work 12 is pushed into a die 121 and sized the outer diameter thereof.

Abstract: Fe-based alloy powder suitable for manufacturing sintered products with excellent corrosion resistance for example, which comprises by weight percentage of not more than 0.03% of C; not more than 2% of Si; not more than 0.5% of Mn; from 8 to 28% of Ni; from 15 to 25% of Cr; from 3 to 8% of Mo; optionally at least one of not more than 5% of Cu; not more than 3 % of Sn; not more than 2% of Nb and not more than 2% of Ti; and the balance being Fe and incidental impurities. The Fe-based alloy powder is sintered in an inert gas such as Ar or H.sub.2, or in an atmosphere of N.sub.2 with pressure of 1 to 10 torr after being compacted. A sintered compact sintered in an atmosphere of N.sub.2 with pressure of higher than 10 torr and not higher than 200 torr is cooled at cooling rate of higher than 50.degree. C./min.

Abstract: A heat resisting alloy for use in exhaust valves and the like low in price and excellent in structural stability, high-temperature strength and hot workability, which consists essentially by weight percentage of C: 0.01.about.0.10%, Si.ltoreq.2.0%, Mn.ltoreq.2.0%, Cr: 14.about.20%, Nb+Ta: 0.3.about.1.5%, Ti: 1.5.about.3.5%, Al: 0.5.about.1.5%, Ni+Co: 35.about.45%, B: 0.001.about.0.01%, one or both of Ca: 0.001.about.0.03% and Mg: 0,001.about.0.03%, and the balance of Fe, additionally the total atomic percentage of Al, Ti, Nb, and Ta: 4.5.about.6.0%, an atomic percentage ratio of Ti/Al: 1.0.about.2.0, and M-value obtained through the following equation.ltoreq.0.925;M=0.717 Ni (atomic fraction)+0.858 Fe (atomic fraction)+1.142 Cr (atomic fraction)+1.90 Al (atomic fraction)+2.271 Ti (atomic fraction)+2.117 Nb (atomic fraction)+1.001 Mn (atomic fraction)+1.90 Si (atomic fraction)+0.777 Co (atomic fraction)+2.224 Ta (atomic fraction).

Abstract: A engine valve having composite structure including a valve stem and a valve head which are made from Ti--Al based alloy and a tail end formed with heat resisting steel are produced by joining a stem end member made from the heat resisting steel to an end of the valve stem made from the Ti--Al based alloy opposite to the valve head by, for example, brazing.

Abstract: A cover with a spray cooling system for the main body of an electric furnace is of a double-layered structure with a hollow inner space in which are provided a plurality of spray nozzles such that cooling water sprayed therefrom will cool the cover. A water collecting box with one or more water outlets is attached to the outer circumferential side surface of the cover such that its bottom surface is below the bottom surface of the cover, and the interior of the box is connected to the hollow inner space of the cover such that the sprayed cooling water can be discharged without the use of a vacuum pump and does not cover the inner surface of the inner space to prevent uniform and efficient cooling of the cover.

Abstract: In the production of stainless steel it is aimed at to depress the highest temperature reaching during refining the molten steel with keeping the necessary tapping temperature so as to prolong the life of refractory materials of the refining furnace. After carrying out decarburization treatment under atmospheric pressure in a refining furnace by blowing an oxygen-containing gas into molten steel, further decarburization of the molten steel and reduction of chromium oxides is carried out under stirring by blowing a non-oxidizing gas under a reduced pressure, and then, reducing agent is charged into the furnace to reduce chromium oxides under keeping the reduced pressure.

Abstract: A process of producing a highly spin-polarized electron beam, including the steps of applying a light energy to a semiconductor device comprising a first compound semiconductor layer having a first lattice constant and a second compound semiconductor layer having a second lattice constant different from the first lattice constant, the second semiconductor layer being in junction contact with the first semiconductor layer to provide a strained semiconductor heterostructure, a magnitude of mismatch between the first and second lattice constants defining an energy splitting between a heavy hole band and a light hole band in the second semiconductor layer, such that the energy splitting is greater than a thermal noise energy in the second semiconductor layer in use; and extracting the highly spin-polarized electron beam from the second semiconductor layer upon receiving the light energy.

Abstract: Bottom ash is taken out of an incinerator after undergoing a moistening process and is subjected to a drying process to reduce its water content to less than 10 weight % or it is taken out of the incinerator with water content less than 10 weight %. Fly ash is taken out of the discharge gas processing system of the incinerator without going through a moistening process. The bottom ash and fly ash, thus taken out, are separately weighed and discharged to a same transporting device and are transported to a melting furnace while being mixed together.

Abstract: An impeller for a high-temperature gas blower suitable for a floating conveyor furnace, having vanes each formed of a dispersion-strengthened alloy which includes as a disperse or internal phase 0.1-2.0% by weight of finely divided particles of an oxide of a high melting-point metal, such as Y.sub.2 O.sub.3, Ce.sub.2 O.sub.3, ZrO.sub.2, Al.sub.2 O.sub.3 and Gd.sub.2 O.sub.3, preferably dispersed in an austenite matrix or external phase of Cr, Fe, Al, Ti and Ni. A gas blower having such impeller, and a furnace using such gas blower are also disclosed.