One embodiment of the present invention relates to a welded member obtained by overlapping portions of two sheets of base metal and performing fillet welding thereon using weld material, and provides a welded member having excellent fatigue strength of welded portion, and a method for manufacturing same, the welded member comprising base metal, a weld bead and root-reinforcing weld metal, wherein the base metal has a tensile strength of 780 MPa, the weld bead has a toe angle of 160 degrees or greater and the weld bead and the root-reinforcing weld metal have a Vicker's hardness of 280-320 Hv and a fatigue strength of 350 MPa or higher.

An exemplary embodiment of the present invention discloses an aluminum-based blank including: a first plated steel plate; a second plated steel plate connected to the first plated steel plate; and a joint connecting the first plated steel plate and the second plated steel plate at a boundary between the first plated steel plate and the second plated steel plate.

Described herein are methods for and devices prepared from welding shape memory alloys. The weld produced from the present methods can approach 100% joint strength relative the ultimate tensile strength of the shape memory alloy, and are substantially free of heat affected zones and brittle intermetallics.

A steel sheet with a tensile strength (TS) of 1180 MPa or more, a member, and a method for producing them. In a region of the steel sheet within 4.9 μm in the thickness direction, a region with a Si concentration not more than one-third of the Si concentration in the chemical composition of the steel sheet and with a Mn concentration not more than one-third of the Mn concentration in the chemical composition of the steel sheet has a thickness of 1.0 μm or more. The lowest Si concentration L.sub.Si and the lowest Mn concentration L.sub.Mn in the region within 4.9 μm in the thickness direction from the surface of the steel sheet and a Si concentration T.sub.Si and a Mn concentration T.sub.Mn at a quarter thickness position of the steel sheet satisfy the following formula (1):

L.sub.Si+L.sub.Mn≤(T.sub.Si+T.sub.Mn)/4  (1).

A method for producing a zinc or zinc-alloy coated steel sheet with a tensile strength higher than 900 MPa, for the fabrication of resistance spot welds containing in average not more than two Liquid Metal Embrittlement cracks per weld having a depth of 100 μm or more, with steps of providing a cold-rolled steel sheet, heating cold-rolled steel sheet up to a temperature T1 between 550° C. and Ac1+50° C. in a furnace zone with an atmosphere (A1) containing from 2 to 15% hydrogen by volume, so that the iron is not oxidized, then adding in the furnace atmosphere, water steam or oxygen with an injection flow rate Q higher than (0.07%/h×α), α being equal to 1 if said element is water steam or equal to 0.52 if said element is oxygen, at a temperature T≥T1, so to obtain an atmosphere (A2) with a dew point DP2 between −15° C. and the temperature Te of the iron/iron oxide equilibrium dew point, then heating the sheet from temperature T.sub.1 up to a temperature T.sub.2 between 720° C. and 1000° C. in a furnace zone under an atmosphere (A2) of nitrogen containing from 2 to 15% hydrogen and more than 0.1% CO by volume, with an oxygen partial pressure higher than 10.sup.−21 atm., wherein the duration t.sub.D of heating of the sheet from temperature T.sub.1 up to the end of soaking at temperature T.sub.2 is between 100 and 500 s., soaking the sheet at T.sub.2, then cooling the sheet at a rate between 10 and 400° C./s, then coating the sheet with zinc or zinc-alloy coating.

The present invention includes a laser-welded lap joint including a weld zone formed by laser lap welding in a lapped portion including a plurality of lapped steel sheets. The weld zone includes a main weld zone that penetrates the steel sheets in the lapped portion and a final weld zone formed at one end of the main weld zone and having a crater, and the weld zone satisfies formulas (1) to (4):
L≥15.0;  (1)
10.0≥L2≥2l.sub.c;  (2)
t1≥2d.sub.c;  (3)
w.sub.c>d.sub.c  (4).

A mobile pipe welding machine includes a welding unit for welding pipes and a pipe receiver for guiding a pipe to the welding unit. The pipe receiver has a distal end facing away from the welding unit and a proximal end facing towards the welding unit. On the distal end there is at least one linearly movable contact body for lifting the pipe.

A grain-oriented silicon steel with low iron loss, wherein the silicon steel is provided with a plurality of grooves on its surface, each of the grooves is 10-60 μm in width and 5-40 μm in depth, and the spacing between adjacent grooves is 1-10 mm. The manufacturing method therefor comprises: scoring the surface of the grain-oriented silicon steel with low iron loss by using a laser in order to form the grooves. The grain-oriented silicon steel with low iron loss can maintain the magnetic domain refining effect in a stress-relief annealing process, and avoid the introduction of more residual stress.

A controlled thermal coefficient product manufacturing system and method is disclosed. The disclosed product relates to the manufacture of metallic material product (MMP) having a thermal expansion coefficient (TEC) in a predetermined range. The disclosed system and method provides for a first material deformation (FMD) of the MMP that comprises at least some of a first material phase (FMP) wherein the FMP comprises martensite randomly oriented and a first thermal expansion coefficient (FTC). In response to the FMD at least some of the FMP is oriented in at least one predetermined orientation. Subsequent to deformation, the MMP comprises a second thermal expansion coefficient (STC) that is within a predetermined range and wherein the thermal expansion of the MMP is in at least one predetermined direction. The MMP may be comprised of a second material phase (SMP) that may or may not transform to the FMP in response to the FMD.

A welded steel part obtained by welding a first sheet with a second sheet, at least one with a coating of aluminum alloy. The welding uses a welding wire which, after melting and cooling, constitutes a weld bead connecting the first sheet to the second sheet and being part of said welded steel part. The respective peripheral edge of the first and second sheets are in a joggled edge type configuration in which the peripheral edge of the first sheet is arranged above, and on or near the upper face of an end portion of the peripheral edge of the second sheet which is extended by an inclined junction portion, at least one part of the upper face of the inclined junction portion delimits at least laterally with the edge of the peripheral edge of the first sheet a groove receiving the weld bead, the inclined joining portion extending by a welding portion in longitudinal continuity with the peripheral edge of the first sheet.