Provided is a technique by which an optical member is marked without degrading the quality of the optical member. The optical member is produced through a removing step (S108, S113) of partially removing a low refractive index layer, which is the outermost layer of a multilayer structure in which the low refractive index layer and a high refractive index layer are layered on each other, by performing non-heating processing on an antireflection film that is formed to cover an optical surface of an optical base member and has the multilayer structure, through irradiation with an ultrashort pulse laser beam so as to expose the high refractive index layer.

A method of joining first and second parts formed of dissimilar materials is provided. The first part defines a first part contacting surface having a frustoconical shape. The first and second parts are brought into contact with one another, with one of the first and second parts being rotated while the other remains stationary, so as to generate frictional heat between the contacting surfaces of the parts, the generated frictional heat producing softened adjacent regions in the first and second parts. A force is applied to the first and second parts to plastically deform the softened adjacent regions and to forge together the first and second parts to form a solid-state joint. A composite torsional damper hub assembly includes a steel stem and a damper hub welded to the stem at an interface. The damper hub is formed of aluminum or an aluminum alloy, and the interface is generally frustoconical.

A method for welding a zinc coated steel sheet is provided. The method for welding a zinc coated steel sheet of the present invention is a method for welding a zinc coated steel sheet by using a welding material, wherein when welding, the welding current is 150-300 A, a shielding gas is a mixed gas of Ar+10-30% CO2, and the welding polarity is alternately altered so that the welding polarity fraction defined by relational equation 1 satisfies the range of 0.25-0.35.

A laser welding method includes a pretreatment process and a welding process. At least one metal member of the plurality of metal members is formed from a metal-plated steel plate in which a base metal has been covered with a coating material that has a melting point lower than the base metal. In the pretreatment process, with the position of the first metal member in the in-plane direction fixed, processing is performed from the front surface of the first metal member to form on the back surface, a protrusion that bulges from the back surface. Then, in the welding process, the first metal member in which a protrusion has been formed is superposed on a second metal member with the protrusion therebetween while maintaining the position in the in-plane direction, and laser light is irradiated on the superposed region to weld the plurality of metal members to each other.

A method of separating a coated substrate includes directing an infrared laser beam onto a first surface of the coated substrate. The coated substrate includes a coating layer disposed on a transparent workpiece, a plurality of defects is disposed within the coated substrate along a contour line that divides a primary region from a dummy region of the coated substrate from a dummy region of the coated substrate. The method also includes translating at least one of the coated substrate and the infrared laser beam relative to each other such that an infrared beam spot traces an oscillating pathway that follows an offset line in a translation direction and oscillates between an inner and outer track line, the oscillating pathway is disposed on the dummy region of the coated substrate, and the infrared laser beam applies thermal energy to the plurality of defects to induce separation of the coated substrate.

A welded blank assembly is formed by welding first and second sheet metal pieces together at a weld joint. At least one of the sheet metal pieces includes a boron steel or press hardenable steel base material layer and an aluminum-based coating material layer, along with a weld notch where at least a portion of the coating material layer is removed before welding. An additional material can be provided during welding to influence weld joint composition and/or a secondary heat source can be used to heat and flow a protective material in a weld region of the blank assembly. The weld notch has a width that may be related to the width of a heat-affected zone formed during welding.

The invention relates to a method to produce a metal blank with a predetermined contour, with the following steps: continuously moving the metal strip in a transport direction x; concurrently removing material from the surface of a top of a metal strip in at least one predetermined surface section by ablation by means of a first laser that is a component of a first removal device, and then concurrently cutting the metal strip along a cutting path corresponding to the contour of the metal blank by means of at least one second laser that is a component of a cutting device provided downstream of the first removal device; the surface section of an upstream metal blank being produced simultaneously with the cutting of a downstream metal blank.

A brazing material is interposed between an aluminum-based material and an iron-based material plated with Ni. The brazing material has a structure in which an Al—Si—Ni based alloy layer and an Al layer are bonded via a flux layer. A structure for brazing is formed such that the Al—Si—Ni based alloy layer is located on the aluminum-based material side and the Al layer is located on the iron-based material side. The structure is heated in a furnace and is thereafter cooled, thereby obtaining a brazed joint body in which the Ni plating that is a barrier layer remains and an Al—Ni layer is formed.

Disclosed are an aluminum-coated blank, a manufacturing method thereof, and an apparatus for manufacturing the same. The blank includes two or more aluminum-coated steel sheets connected together by a joint, each of the steel sheets including: a base steel sheet including 0.01-0.5 wt % of carbon, 0.01-1.0 wt % of silicon, 0.5-3.0 wt % of manganese, greater than 0 but not greater than 0.05 wt % of phosphorus, greater than 0 but not greater than 0.01 wt % of sulfur, greater than 0 but not greater than 0.1 wt % of aluminum, greater than 0 but not greater than 0.001 wt % of nitrogen, and the balance of iron and other inevitable impurities; and a coating layer including aluminum and formed on at least one surface of the base steel sheet.

A method for laser soldering includes selecting a copper-containing material as a filler material, supplying the filler material at a butt joint of two components, and melting the filler material in a main process zone by means of laser radiation in an advancement direction. The filler material in the main process zone is melted by means of laser radiation of a wavelength λH in the blue or green spectral range with 400 nm≤λH≤600 nm.