A circumferential welded joint of a line pipe is formed by butting against each other end portions of steel pipes having a yield strength according to 5L Specification of API Standards not smaller than 555 N/mm.sup.2 and welding the butted portions in a circumferential direction. A joint strength ratio σ.sub.match=(TS-w/TS-b).Math.(YS-w/YS-b) represented by a product of a ratio between a tensile strength TS-w of a weld metal and a tensile strength TS-b of a base material and a ratio between a yield strength YS-w of the weld metal and a yield strength YS-b of the base material, and a critical equivalent plastic strain ε.sub.p-cri [%] for ductile crack generation in a base material heat affected zone satisfy Equation (1), and the yield strengths YS-w, YS-b of the weld metal and base material satisfy Equation (2).
σ.sub.match>4.85ε.sub.p-cri.sup.−0.31  (1)
YS-w/YS-b≧1.0  (2)

A friction stir welding method for welding steel sheets together includes a heating device disposed ahead of a rotating tool in an advancing direction that preheats an unwelded portion before the welding thereof by the rotating tool and at the time of preheating, the surface temperature distribution in a direction perpendicular to the advancing direction in a position at which the welding by the rotating tool is initiated is set such that given that T.sub.Ac1 is the Ac.sub.1 point of a steel sheet, the maximum temperature (T.sub.U) thereof is 0.6×T.sub.Ac1<T.sub.U<1.8×T.sub.Ac1, and given that L is the width of the heating region exceeding a temperature (T.sub.L)=0.6×T.sub.Ac1, 0.3×d≦L≦2.0×d is satisfied with a diameter (d) of the shoulder.

A method and system to manufacture workpieces employing a high intensity energy source to create a puddle and at least one resistively heated wire which is heated to at or near its melting temperature and deposited into the puddle as droplets.

A method, a component part of an end fitting and a preformed member for manufacturing a component part of an end fitting are disclosed. The method comprises the steps of, via an additive process, providing a near net shape (NNS) precursor corresponding to a component part of an end fitting layer-by-layer and subsequently performing at least one post NNS processing operation on the NNS precursor to provide the component part.

A high resolution system for additive manufacturing, soldering, welding and other laser processing applications. A blue laser system for additive manufacturing, soldering, welding and other laser processing applications and operation for additive manufacturing of materials.

A visible light laser system and operation for welding materials together. A blue laser system and operation for welding conductive elements, and in particular thin conductive elements, together for use in energy storage devices, such as battery packs.

A method comprising the steps of: distributing a titanium alloy or pure titanium powder layer on a work table inside a vacuum chamber, directing at least one electron beam from at least one electron beam source over the work table causing the powder layer to fuse in selected locations, distributing a second powder layer on the work table of a titanium alloy or pure titanium inside the build chamber, directing the at least one electron beam over the work table causing the second powder layer to fuse in selected locations, and releasing a predefined concentration of the gas from the metal powder into the vacuum chamber when at least one of heating or fusing the metal powder layer, wherein at least one gas comprising hydrogen is absorbed into or chemically bonded to the titanium or titanium alloy powder to a concentration of 0.01-0.5% by weight of the hydrogen.

A method for forming a three-dimensional article through successive fusion of parts of a metal powder bed is provided, comprising the steps of: distributing a first metal powder layer on a work table inside a build chamber, directing at least one high energy beam from at least one high energy beam source over the work table causing the first metal powder layer to fuse in selected locations, distributing a second metal powder layer on the work table, directing at least one high energy beam over the work table causing the second metal powder layer to fuse in selected locations, introducing a first supplementary gas into the build chamber, which first supplementary gas comprising hydrogen, is capable of reacting chemically with or being absorbed by a finished three-dimensional article, and releasing a predefined concentration of the gas which had reacted chemically with or being absorbed by the finished three dimensional article.

An apparatus and method for protecting an inner radial surface of a radial member of a turbomachine from corrosion are provided. The method may include shaping the inner radial surface of the radial member and a corresponding outer radial surface of a corrosion-resistant liner. The method may also include heating the radial member to increase a diameter of the inner radial surface of the radial member, and inserting at least a portion of the corrosion-resistant liner into the radial member. The method may further include attaching the corrosion-resistant liner to the inner radial surface of the radial member to thereby protect the inner radial surface of the radial member of the turbomachine from corrosion.

The method of metal-thermoplastic resin direct bonding is characterized by comprising a first step for irradiating a surface of the metal material with a pulse laser under an oxidizing atmosphere to form a surface modification region, a second step for causing the thermoplastic resin material to abut against the surface modification region to form a bonding interface, and a third step for heating up the bonding interface by laser irradiation to achieve bonding, the first step including forming metal oxide particle clusters obtained when metal oxide particles having a particle diameter of 5-500 nm to be continuously bonded at the surface modification region, so that the maximum height (Sz) of a surface of the metal oxide particle clusters is 50 nm-3 .Math.m.