Gas-shielded welding wire for welding high-strength steel

Abstract

The invention relates to a solder which is protected by the gas for soldering high intensity and high toughness steel. The main aim solutes the question that the intensity and the toughness of the welding line of the jointing material which is protected by the gas that the high intensity and the high toughness of the new steel used doesn't match at the present. Its technique measure is that its chemic component weight percent of the solder is C 0.04~0.12,Mn 1.50~2.10,Si 0.50~1.0,Ni 0.9~2.0,Ti 0.09~0.25,B 0.002~0.010,Cu 0.10~0.55,Cr 0.20~0.60,S <=0.015,P <=0.020 and Als <=0.015,and the leavingses are Fe and other inevitable impurity substances. The solder in the present invention adopts the mixed gas (80% Ar + 20% CO2) to protect. The metal resisted drawing intensity of the welding line of the invention reaches to 805MPa and the -30 Deg. C impact power is Akv >= 127J.

Description

1. Technical field [0001] The invention relates to a gas-shielded welding wire for welding metal materials, especially suitable for welding 800MPa high-strength and high-toughness steel for engineering structures. 2. Background technology [0002] With the continuous improvement of the strength and toughness of new steel types for construction machinery, there is a large gap between the strength and toughness of existing welding wire welds and base materials. High-strength series welding materials need to be imported in large quantities every year, which cannot meet the needs of key domestic projects. In order to meet the needs of gas-shielded welding materials for the new generation of high-performance engineering structural steel in my country's construction machinery, oil pipelines, pressure vessels, and automobile manufacturing industries, it is urgent to develop a new generation of high-strength and high-toughness gas-shielded welding wire. Gas shielded welding has the ...

AI Technical Summary

Problems solved by technology

The disadvantage of this welding wire is that the tensile strength of the weld metal is lower than 700MPa, and the low temperature impact toughness is poor

Although the deposited metal of ST700 mixed gas shielded welding wire produced by ESAB has reached 700MPa, its shortcoming is that its low-temperature impact toughness is poor, which cannot meet the requirements of the structure in low-temperature service.

Japanese patent P2000-218391A introduces a gas-shielded welding wire. The weld metal of this welding wire has good low-temperature impact toughness, but the disadvantage is that the tensile strength cannot reach 700MPa stably.

Low-temperature impact toughness cannot meet the technical requirements for matching the strength and toughness of high-strength engineering series structural steels in low-temperature service

Chinese patent publication number is the patent of CN1413795A, although its welding wire can be matched with the high-strength steel of 700-800MPa to use, its deficiency is because Ni content is higher, easily breaks in the drawing of welding wire, and manufacturing process is relatively complicated, and Also, due to the more expensive Mo element, the production cost increases