A welded steel part with a very high mechanical strength is provided. The welded steel part is obtained by heating followed by hot forming, then cooling of at least one welded blank obtained by butt welding of at least one first and one second sheet. The at least one first and second sheets including, at least in part, a steel substrate and a pre-coating which includes an intermetallic alloy layer in contact with the steel substrate, topped by a metal alloy layer of aluminum or aluminum-based alloy. A method for the fabrication of a welded steel part and the fabrication of structural or safety parts for automotive vehicles are also provided.

Embodiments of the present disclosure are directed to coiled steel tubes and methods of manufacturing coiled steel tubes. In some embodiments, the final microstructures of the coiled steel tubes across all base metal regions, weld joints, and heat affected zones can be homogeneous. Further, the final microstructure of the coiled steel tube can be a mixture of tempered martensite and bainite.

A method for post-weld heat treatment of a without a filler material welded high strength component made of a gamma prime () strengthened superalloy can include providing the welded component, heating the welded component by applying a rapid heating-up rate in the range of 20 C./min to 40 C./min during the entire temperature range from room temperature (RT) up to a temperature T.sub.1 of at least 1000 C., holding the welded component at T.sub.1 and then heating the component by applying a slow heating-up rate of about 5 C./min to a final temperature T.sub.f, then holding the welded component at T.sub.f for a time t.sub.f sufficient for at least partially dissolving the gamma prime phase in a weld of the welded component and also in a base material surrounding the weld, and cooling the component with a cooling rate that is greater than or equal to about 20 C./min.

A deformed part in a case in which the application of a collision load causes bending deformation in a structural member for an automobile body having a hardness distribution (strength distribution) composed of a quenched part, a base metal hardness part, and a transition part in a longitudinal direction is used as the base metal hardness part to avoid plastic strain concentration in the quenched part.

This structural member for an automobile body has a hollow steel main body having a rectangular cross section. The main body includes a quenched part, a base metal hardness part, and a transition part in this order, in at least a part thereof in an axial direction. The length (L) of the transition part as related to the axial direction satisfies the relationship of 0.006 (mm.sup.1)<LA/I0.2 (mm.sup.1) in a case in which the cross-sectional area of the main body is (A) and the moment of inertia of area is (I).

A method of fabricating of an object includes causing a first heat source to heat a feed material to form a melt pool of the feed material on a surface. The method further includes causing a second heat source to heat the melt pool on the surface to regulate grain formation of the feed material in the melt pool as the melt pool cools and solidifies on the surface to form at least a portion of the object. The method also includes causing the first heat source and the second heat source to move relative to the surface as the melt pool is formed and cooled.

A method for producing a welded blank (1) includes providing two precoated sheets (2), butt welding the precoated sheets (2) using a filler wire. The precoating (5) entirely covers at least one face (4) of each sheet (2) at the time of butt welding. The filler wire (20) has a carbon content between 0.01 wt. % and 0.45 wt. %. The composition of the filler wire (20) and the proportion of filler wire (20) added to the weld pool is chosen such that the weld joint (22) has (a) a quenching factor FT.sub.WJ: FT.sub.WJ0.9FT.sub.BM0, where FT.sub.BM is a quenching factor of the least hardenable substrate (3), and FT.sub.WJ and FT.sub.BM are determined: FT=128+1553C+55Mn+267Si+49Ni+5Cr79Al2Ni.sup.21532C.sup.25Mn.sup.2127Si.sup.240CNi4NiMn, and (b) a carbon content C.sub.WJ<0.15 wt. % or, if C.sub.WJ0.15 wt. %, a softening factor FA.sub.WJ such that FA.sub.WJ>5000, where FA=10291+4384.1Mo+3676.9Si522.64Al2221.2Cr118.11Ni1565.1C246.67Mn.

A process for manufacturing a bimetallic part by means of a first component formed by a first aluminum alloy and a second component formed by a second aluminum alloy, said process involving: assembling the first component and the second component to obtain an assembled part; applying a thermal treatment to the assembled part at a temperature of 100 to 250 C., the thermal treatment causing the assembled part to deform, in particular as a result of a metallurgical deformation by a precipitation of hardening phases of the first component and/or the second component; cooling the part to ambient temperature, upon which the part remains deformed. The process involves, prior to the assembling step, an estimation of the degree of deformation that the assembled part will undergo under the effect of the thermal treatment.

A high strength electric resistance welded steel pipe has a yield strength of 450 MPa or more and excellent resistance to softening for a long period in an intermediate temperature range and a method of manufacturing the steel pipe are provided. The steel pipe has a chemical composition containing, by mass%, C: 0.026% or more and 0.084% or less, Si: 0.10% or more and 0.30% or less, Mn: 0.70% or more and 1.90% or less, Al: 0.01% or more and 0.10% or less, Nb: 0.001% or more and 0.070% or less, V: 0.001% or more and 0.065% or less, Ti: 0.001% or more and 0.033% or less, Ca: 0.0001% or more and 0.0035% or less, in which the condition that Pcm is 0.20 or less is satisfied.

A weld bead shaping apparatus including: a gouging torch for gouging an object to be shaped; a shape sensor for measuring a shape of the object; a slider apparatus and an articulated robot for driving the gouging torch and shape sensor; an image processing apparatus; and a robot controlling apparatus. The image processing apparatus includes: a shape data extracting unit extracting shape data of the object, from a measurement result obtained by the shape sensor; and a weld reinforcement shape extracting/removal depth calculating unit calculating a weld reinforcement shape of the weld bead from a difference between the shape data and a preset designated shape of the object, and calculating a removal depth by which gouging is performed, based on the weld reinforcement shape. The robot controlling apparatus controls the slider apparatus, the articulated robot, and the gouging torch based on the weld reinforcement shape and the removal depth.

A method for producing a welded blank (1) includes providing two precoated sheets (2), butt welding the precoated sheets (2) using a filler wire. The precoating (5) entirely covers at least one face (4) of each sheet (2) at the time of butt welding. The filler wire (20) has a carbon content between 0.01 wt. % and 0.45 wt. %. The composition of the filler wire (20) and the proportion of filler wire (20) added to the weld pool is chosen such that the weld joint (22) has (a) a quenching factor FT.sub.WJ: FT.sub.WJ0.9 FT.sub.BM0, where FT.sub.BM is a quenching factor of the least hardenable substrate (3), and FT.sub.WJ and FT.sub.BM are determined: FT=128+1553C+55Mn+267Si+49Ni+5Cr79Al2Ni.sup.21532C.sup.25Mn.sup.2127Si.sup.240CNi4NiMn, and (b) a carbon content C.sub.WJ<0.15 wt. % or, if C.sub.WJ0.15 wt. %, a softening factor FA.sub.WJ such that FA.sub.WJ5000, where FA=10291+4384.1Mo+3676.9Si522.64Al2221.2Cr118.11Ni1565.1C246.67Mn.