Gas shielded welding wire matched with weather-resistant bridge steel Q690qE and preparation method thereof

Abstract

The invention discloses a gas shielded welding wire and a preparation method thereof. The welding wire comprises the following components of, in percentage by weight, 1.40% to 1.80% of Mn; 2.00% to 3.00% of Ni; 0.30% to 0.65% of Mo; greater than 0 and less than or equal to 0.10% of C; greater than 0 and less than or equal to 0.60% of Si; greater than 0 and less than or equal to 0.010% of S; greater than 0 and less than or equal to 0.010% of P; greater than 0 and less than or equal to 0.60% of Cr; greater than 0 and less than or equal to 0.35% of Cu; greater than 0 and less than or equal to 0.005% of Ti; greater than 0 and less than or equal to 0.005% of V; and the balance Fe and other impurities. The preparation method comprises the following steps of (a) preparing a disc strip according to the formula of the welding wire, and then drawing the disc strip roughly; (b) annealing the disc strip treated in the step (a) to remove an oxidation layer on the surface of the disc strip; (c) roughly drawing the disc strip treated in the step (b) again to a certain specification; and (d) finely drawing the disc strip treated in the step (c), plating copper on the surface of the disc strip, andwinding the disc strip. According to the gas shielded welding wire, through a reasonable welding process, the tensile strength of weld metal is greater than 810 MPa and the yield strength is larger than 755 MPa, which is close the mechanical property of a base material, and meets the mechanical property requirement of the bridge steel Q690qE.

Description

technical field [0001] The invention belongs to the technical field of welding materials, and in particular relates to a weather-resistant bridge steel Q690qE matching gas-shielded welding wire and a preparation method thereof. Background technique [0002] With the rapid development of the national economy and modern industry, my country's welded steel bridges have been widely used in bridge construction due to their unique advantages such as light weight, large span, good earthquake resistance, and easy repair and replacement. Due to the service environment and performance requirements, traditional steel can no longer meet its design and construction requirements. Steel for bridges must have the characteristics of high strength, lightweight structure, large thickness, excellent low temperature impact toughness, excellent weldability, and excellent corrosion resistance. [0003] With the first design and application of weather-resistant bridge steel Q690qE in actual product...

AI Technical Summary

Problems solved by technology

However, this flux is suitable for submerged arc welding process. For submerged arc welding process, there are disadvantages such as difficult construction in bridge structures with complex structures.

[0005] Patent CN21021520025B discloses a gas shielded welding with a tensile strength of 900 MPa. Its main alloy system is Mn-Ni-Mo, in which the content of Ti element is relatively high, and the carbon equivalent of the welding wire is 0.7-0.85. The tensile strength of the deposited metal is between 940-1010MPa, which matches the 900MPa grade steel. However, it is found through relevant experiments that the weather resistance of the deposited metal after welding with the welding wire disclosed in this patent is poor, and the weldability of the welding wire is poor. The seam formation is poor, and the deposited metal after welding with this welding wire does not match the Q690QE bridge steel, so it is not suitable for Q690QE bridge steel

[0006] Patent CN104227264B discloses a solid wire for gas-shielded arc welding of high-strength steel, which can obtain weld metal with appropriate strength and good toughness in low-temperature regions in the welding of 780-grade high-strength steel, and has excellent welding workability , but there are many Ti elements added in the welding wire, the welding performance of the welding wire is poor, it is easy to produce spatter during welding, and the weld seam is not beautiful

Images