| 摘要 |
<p>The welded structures are designed for the civil engineering and have tensility strength higher than 900 MPa (130 ksi) and the metal of the welded seams has fracture strength meeting with the requirements for application in cryogen temperatures. The method for welding the basic metal includes the stage of welding where welding process in protected gas medium is used, protected gas based on argon and fusible welding wire where metal of the welding seam is produced having the temperature of the transition from plasticity to brittleness, lower than -73 deg.C (-100 deg. F) which metal has fine grain volume centred cubic crystalline structure consisting of at least 50 vol.% self-annealed plastic martensite and less than 250 per mm2 nonmetallic inclusions with diameters larger than 1000 nm determined on the surface of a small plate of the metal of the welding seam. The metal of the welding seam contains iron and the following alloying elements, in wt.%: carbon 0.06-0.10, manganese from 1.60 to 2.05, silicon from 0.20 to about 0.32, nickel from 1.87 to 6.00, chromium from 0,30 to about 0.87 and molybdenum 0.40-0.56. By the method welded structures are produced having tensility strength larger than about 900 MPa (130 ksi). 12 claims, 2 figures</p> |
