900MPa-level high-performance gas shielded welding wire

Abstract

The invention provides a 900MPa-level high-performance gas shielded welding wire, which is suitable for welding large-sized important structural members in the heavy load fields of engineering machinery, coal mine machinery, railroad bridges, automobile cranes, high pressure vessels and the like. The gas metal arc welding welding wire comprises the following chemical components in percentage by mass: 0.05 to 0.10 percent of C, 0.40 to 0.80 percent of Si, 1.60 to 2.00 percent of Mn, 2.0 to 2.6 percent of Ni, 0.3 to 0.7 percent of Mo, 0.20 to 0.60 percent of Cr, 0.02 to 0.08 percent of Ti, 0.002 to 0.006 percent of B, 0.02 to 0.08 percent of Zr, less than or equal to 0.010 percent of S, less than or equal to 0.010 percent of P, less than or equal to 0.003 percent of O, less than or equal to 0.007 percent of N, and the balance of Fe and inevitable impurities. The welding wire adopts Ar+20 percent CO2 gas shielded welding rich in argon, can be used for welding high-strength low ally steel of which the tensile strength Rm is more than or equal to 900MPa, and a weld metal has high obdurability and cracking resistance under a welding condition and a post-welding hardening and tempering condition.

Description

technical field [0001] The invention belongs to the field of welding materials, specifically a high-strength and high-toughness gas-shielded welding wire with low impurity content and Ti, B, Zr microalloying, using Ar+20% CO 2 Argon-rich gas shielding can weld low-alloy high-strength structural steel with a strength level greater than 900MPa. Background technique [0002] The continuous development of science and technology has put forward higher and higher requirements for the performance of steel used in engineering structures and mechanical parts, not only must have high strength, but also have good plasticity, toughness and excellent welding process performance. The new generation of 900MPa grade high-strength structural steel has fine-grained, ultra-clean, high-uniformity, high-strength, high- With the characteristics of toughness and good comprehensive performance, it has been applied in heavy-duty fields such as mining machinery, bridges, railways, and truck cranes. ...

AI Technical Summary

Problems solved by technology

However, the low-temperature impact toughness of the weld metal of the former welding wire is low, while the latter welding wire contains precipitation strengthening elements V and Nb, which will lead to a significant increase in the strength of the weld metal and a significant decrease in impact toughness during the post-weld heat treatment process. , at the same time, the content of S and P in the welding wire is controlled below 0.10, which is obviously too high, which is not conducive to the crack resistance and low temperature toughness requirements of the weld metal

Images