High-toughness gas protective welding wire for large-linear energy welding low-alloy steel

Abstract

The invention relates to a high-toughness gas protective welding wire for large-linear energy welding low-alloy steel. The technical scheme is that the welding wire comprises the following chemical components in percentage by weight: 0.02-0.12 percent by weight of C, 1.00-2.50 percent by weight of Mn, 0.05-0.50 percent by weight of Si, 0.03-0.30 percent by weight of Ti, 0.001-0.004 percent by weight of B, less than or equal to 0.50 percent by weight of Cr, less than or equal to 0.5 percent by weight of Mo, less than or equal to 0.025 percent by weight of S, less than or equal to 0.025 percentby weight of P, 0.03-0.3 percent by weight of two or three kinds of Ca, Mg and Ba and the balance of Fe and inevitable impurities. The high-toughness gas protective welding wire is manufactured by thefollowing steps: carry out steel making on molten iron or scrap steel or the molten iron and the scrap steel by adopting a converter or an electric arc furnace, and then refining and adjusting molteniron components, casting into square billets, and then rolling into coil rods and cold-drawing into welding wires by conventional processes. The prepared welding material has good metal welding toughness and high tensile strength and is suitable for the welding of low-alloy high-strength steel under the condition of large-linear energy welding condition of 100-800kj / cm.

Description

technical field [0001] The invention belongs to the technical field of gas shielded welding wire. Specifically relates to a high-toughness gas-shielded welding wire for welding low-alloy steel with large input energy. Background technique [0002] In the past 30 years, in order to improve the welding efficiency of large-scale engineering structures and ensure the safety and reliability of their use, single-side submerged arc welding, gas-electric welding, electroslag welding and other high-energy welding technologies with high welding efficiency have been adopted one after another. The traditional low-alloy high-strength steel has brought new problems, that is, the strength and toughness of the weld and the heat-affected zone (HAZ) of the welded coarse grain are deteriorated, and defects such as welding cold cracks are prone to occur. Therefore, the improvement of weld seam and HAZ toughness has become a hot spot and focus in the research and development of high-input energ...

AI Technical Summary

Problems solved by technology

[0005] 1. The content of Si in the welding material is relatively high, because a higher content of Si will promote the formation of M / A and reduce the toughness of the weld and welding heat-affected zone (HAZ);

[0006] 2. The welding material contains one or more of expensive metals such as Ni, Cr, Mo, Cu and other precious alloying elements, which increases the cost of the product;

[0007] 3. The welding material contains rare earth elements. Rare earth elements are very active elements, which are not easy to control, and are easy to pollute the weld metal, which is not conducive to the improvement of the quality of welded joints.