Abstract: A distributor rotor electrode comprising an electrode head having a pair of flat surfaces substantially parallel to a plane of rotation of the rotor electrode and a generally arcuated, convexed discharge surface perpendicular to the plane of rotation to define a discharge gap on it. The electrode head has an electrically high-resistance layer attached to at least the pair of substantially flat surfaces, and comprises a material including a ceramic effective to suppress noise electromagnetic wave radiation at the discharge surface. The high-resistance layer material may comprise 10% to 70% of SiC and a mixture of SiOx, Si and C and may be attached to the discharge surface as well as to the flat surfaces, or to the flat surfaces only to expose the arcuated discharge surface to the discharge gap. The arcuated discharge surface may have ridges and grooves extending generally perpendicularly to the plane of rotation, and may have a wave-shaped or comb-shaped contour.

Abstract: A laser vapor deposition apparatus includes a vacuum chamber which includes an exhaust port and in which a material to be vaporized and a substrate are enclosed, a laser beam source for irradiating the material to be vaporized with a laser beam so as to deposit from the material a desired compound onto the substrate, and a gas supply source which supplies to the surface of the material, a gas that can prevent changes in property of the material which could be caused by the laser beam irradiation.

Abstract: A control apparatus for energy beam hardening which has an electromagnetic wave detector for detecting an electromagnetic wave irradiated from the surface of a hardened portion to which an energy beam is being emitted, a temperature converter for converting a detection signal from the electromagnetic wave detector to a temperature, hardening characteristics presuming means for presuming hardening characteristics by processing temperature distribution data from the temperature converter, energy beam deciding means for deciding the output and moving velocity of the energy beam emitted to obtain desired hardening characteristics and according to hardening characteristics to be presumed, and energy beam control means for controlling at least one of the output and moving velocity of the energy beam according to the output of the energy beam deciding means to thus suppress the irregularities in the hardening characteristics, thereby obtaining hardening characteristics of the hardened material as desired even if pre

Abstract: A noble metal coating method of coating an underlying metal with a noble metal comprises the steps of feeding a mixture comprising the noble metal, an oxide film removing agent, such as borax, and a binder for binding the metal and the agent to each other to a portion of the underlying metal that is to be coated and irradiating a laser beam onto the mixture on the underlying metal.

Abstract: A method and apparatus for detecting and regulating a focused condition of an electron beam emitted from an electron gun of an electron beam welding apparatus. An electron beam of a low intensity is first directed onto the workpiece. The coil current of an electromagnetic condenser lens used to focus the electron beam is then varied linearly. The resulting electrons and other radiation produced from the workpiece as a result of this irradiation is then sensed and a signal corresponding to the intensity thereof is produced. The focus position of the electron beam is determined in accordance with variations in this signal.

Abstract: A short circuiting arc welding machine increases an arc current density by adding a pulsed current having upper and lower limits to a current flowing when an arc is produced, thereby increasing the depth of bead penetration into a workpiece, removing welding defects, and speeding up the welding operation. The welding machine is capable of alternately changing the direction of flow of a welding current at desired periods to produce arcs in straight, reverse and mixed polarities for achieving intermediate characteristics of arcs of straight and reverse polarities, with a resultant ability to adjust in a wide range a wire melting rate and the amount of heat applied to the workpiece.

Abstract: A short circuit transfer arc welding machine including a wire electrode which is fed towards a base metal, a DC source for applying a voltage across the base metal and the wire electrode, a switching element for interrupting the voltage, a voltage detector for detecting a voltage developed across the base metal and the wire electrode, a first comparator for determining when a detection voltage outputted by the voltage detector reaches a voltage value corresponding to the short circuiting of the base metal and wire electrode, a second comparator for determining when the detection voltage of said voltage detector reaches an arc discharge voltage, and a switching element control circuit for closing the switching element in response to a signal from the first comparator and for opening the switching element in response to a signal from the second comparator.

Abstract: A DC welding device is provided with an adder which sums the signals from a base current setting circuit and a shorting current setting circuit and applies the same to a welding current control unit. When a short circuit occurs, the shorting current circuit outputs a gradually increasing signal until the short is removed, whereupon a gradually decreasing signal, which reaches zero after a predetermined time, is output.

Abstract: A process for preparing a press die comprises forming a metal overlaid on a base metal which is different in kind from the overlaid metal, and cutting the base metal together with overlaid metal into a predetermined shape.

Abstract: In a welding apparatus for overlaying on a base metal, a reverse polarity soft plasma arc is formed between an electrode and the base metal and a welding rod is fed into the arc to weld the base metal by melting the welding rod and the feeding speed of the welding rod is controlled corresponding to the arc current to form a bead having low penetration.The electrode is oscillated and an active gas such as CO.sub.2 or O.sub.2 is incorporated in a shield gas at a rate controlled corresponding to the oscillation of the electrode.

Abstract: An arc welding apparatus and method is described which includes a guide nozzle surrounding a non-consumable electrode and a shielding nozzle disposed outside the guide nozzle so as to feed a protecting inert gas about the electrode from a position within the guide nozzle and to feed a shielding carbon dioxide gas or a mixture of carbon dioxide gas and oxygen or other inert gas from a position within the shielding nozzle, whereby the electrode is protected by means of the guide nozzle and the protecting gas supplied therethrough and the outer portion of the arc is cooled to restrict the radial extent thereof by the shielding gas, while a deoxidizing reaction with the melted metal may be performed by means of the carbon dioxide gas and a deoxidizing agent within a welding rod when the latter is employed between the electrode and a base metal, or in the vicinity of the welding arc.

Abstract: A method of removing surface defects from the surface of a steel product, such as a slab designed for rolling, wherein the defects are melted by an arc generated by an arc welding apparatus having a non-consumable electrode, a guide nozzle about the electrode to maintain an inert gas atmosphere immediately thereabout, and a shield nozzle about the guide nozzle to inject a mainly carbon dioxide gas therefrom, and a deoxidizer is applied to the molten pool formed in the welding operation so as to cover the surface thereof with a slag formed by the deoxidizer which is oxidized.