Abstract: A laser welding method is usable to weld a material containing copper as a main component. The laser welding method includes heating the material by irradiation with a first laser light and welding the material by irradiation of a portion, which has been irradiated with the first laser light, of the material with a second laser light with which an energy absorption rate of the copper contained in the material increases by an increase in a temperature of the material. A wavelength of the first laser light is 400 nm to 470 nm.

Abstract: Realized is a welding wire containing flux used for a gas shielded arc welding of a direct current/positive polarity mode, with use of which a quantity of sputter generated is small, a good weldability is realized and a weld metal with an excellent toughness is obtained in all the welding positions under application of a welding current in the range of a low current to a medium current, or in a definite manner in the range of 50 to 300 A. The flux contains 0.7 to 3 wt % Al, 0.1 to 1.0 wt % Mg and 1.2 to 5 wt % BaF2, each content being a value in wt % to a total weight of the wire and the sum of a content of Al plus a content of Mg multiplied by 3 being in the range of 1.3 to 5 wt %, a filling ratio of the flux to the total weight of the wire is in the range of 5 to 30 wt %, a total Mn content in a steel sheath and the flux combined is in the range of 0.2 to 1.9 wt % and a total Si content in the steel sheath and the flux combined in the range of 0.001 to 0.9 wt %.

Abstract: An injection mold device comprises a first matrix attached to a movable platen and a second matrix attached to a fixed platen. A multiplicity of first cavity units are attached to the first matrix. A multiplicity of second cavity units are provided for selective removable attachment to the first matrix during a mold-clamping state and to the second matrix during a mold-opening state. A self-holding device is associated with the first matrix for maintaining a clamping force between the first cavity units and the second cavity units during the mold-clamping state. A mold-opening device is associated with the second matrix for removably attaching the second cavity units to the first matrix in the mold-clamping state and for removing the second cavity units from the first matrix in the mold-opening state.

Abstract: There are disclosed flux cored wire electrodes for self-shielded arc welding which comprise a steel sheath filled with a powdery flux containing as essential components thereof the following components set forth in terms of weight percentage: BaF.sub.2 (25-70), alkali metal fluoride (1-30), compound oxide composed of the oxide of an alkaline earth metal selected from among Ca, Sr, and Ba and the oxide of a metal selected from among Fe, Mn, Ni, Co, Ti, Al and Zr (1-30), Al (3-12), Mg (2-10) and Mn (0.5-10).

Abstract: A flux-cored wire electrode suitable for use in gas-shielded arc-welding, characterized in that the sum of the carbon content in the sheath made of soft steel and the carbon content in a lubricant adhered on the sheath is 0.045 wt. % or lower relative to the total weight of the sheath and a flux, which contains 20-50 wt. % of TiO.sub.2, 1-15 wt. % of SiO.sub.2, 2.5-10 wt. % of ZrO.sub.2, 0.1-5 wt. % of an arc-stabilizing agent, 10-45 wt. % of a deoxidizer and up to 50 wt. % of iron powder, all based on the total weight of the flux, is filled to an amount of 10-30 wt. % of the total weight of the wire electrode in the cavity surrounded by the sheath. The above flux-cored wire electrode features a low fume emission rate comparable with that of a solid wire electrode.

Abstract: The present invention relates to a coated welding electrode containing at least 0.5% of Cr based on the total weight of the welding electrode and comprising a metal core and a coating flux composition. In this welding electrode, the content of Na and K components in the coating flux calculated as (Na.sub.2 O + K.sub.2 O) is reduced below 1% based on the total weight of the coating flux composition, whereby amounts of fumes generated at the welding step, especially the amount of toxic soluble Cr, are suppressed and minimized.