CN101987403B

CN101987403B - 900MPa-level high-performance gas shielded welding wire

Info

Publication number: CN101987403B
Application number: CN2010105809334A
Authority: CN
Inventors: 国旭明; 莫春立; 马红岩; 高双胜; 张占伟
Original assignee: Shenyang Aerospace University
Current assignee: Shenyang Aerospace University
Priority date: 2010-12-09
Filing date: 2010-12-09
Publication date: 2012-11-07
Anticipated expiration: 2030-12-09
Also published as: CN101987403A

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

A kind of 900MPa level high performance gas protection welding wire

Technical field

The invention belongs to field of welding material, it is low to be specially a kind of impurity content, and the high-strength high-tenacity gas shielded welding wire of Ti, B, Zr microalloying adopts Ar+20%CO ₂Argon-rich gas shielded, but the weld strength rank is greater than the low-alloy high-tensile structural steel of 900MPa.

Background technology

The continuous development of science and technology has proposed increasingly high requirement to the performance of engineering structure and the employed steel of machine components, not only will have high intensity, but also will have good plasticity, toughness and excellent welding processing properties.Other high-tensile structural steel of the 900MPa of a new generation level obtains characteristics such as fine grain, ultra cleanliness factor, high uniformity, high strength, high tenacity and good combination property through control carbon content, impurity content, microalloying and means such as controlled rolling process and modifier treatment, be applied in heavily loaded fields such as mining machinery, bridge, railway, autocranes.Based on the characteristics of high-strength steel of new generation self, require supporting with it welding material also should have high cleanliness factor, high obdurability and good cracking resistance.Yet the tensile strength that in existing welding material, can guarantee weld metal is few greater than the gas protecting welding wire of 900MPa, mainly contains ED-FK1000 solid core welding wire and Chinese invention patent disclosed " 90 kilogram-scale low welding crack sensibility high-strength steel plates are used welding wire " (publication number CN101244495) that Sweden OERLIKON company produces.But the low-temperature impact toughness of the weld metal of preceding a kind of welding wire is lower; In then a kind of welding wire owing to contain precipitation strength element V and Nb; In the post weld heat treatment process, will cause the intensity of weld metal significantly to increase, impact flexibility obviously descends, and S, P content are controlled at below 0.10 in this welding wire simultaneously; Obviously higher, be unfavorable for the crack resistance and the low-temperature flexibility requirement of weld metal.

Summary of the invention

The object of the present invention is to provide that a kind of impurity content is low, the grade gas shielded welding wire of the 900MPa of microalloying; Greater than 900MPa, and have good plasticity, toughness and cracking resistance by its tensile strength that adopts the deposited metal that argon-rich gas shielded welding obtains.

For realizing above-mentioned purpose, the present invention adopts following technical proposals:

(mass percent %) is the main chemical compositions of welding wire: C 0.05-0.10, Si 0.40-0.80, Mn 1.60-2.00; Ni 2.0-2.6, Mo 0.3-0.7, Cr 0.20-0.60, Ti 0.02-0.08; B0.002-0.006, Zr 0.02-0.08, S≤0.010, P≤0.010; O≤0.003, N≤0.007, surplus is Fe and unavoidable impurities.

Existing foundation with welding wire chemical composition design of the present invention is narrated as follows:

Chemical composition C is the key factor of proof strength, but also is to cause crisp element in the high-strength steel weld seam, and influences the cracking resistance and the impact flexibility of weld metal, so want the carbon content in the strict control welding wire, makes weld metal produce low-carbon martensite.Adding Mn, Ni element can make the CCT curve move to right, and impel the formation of weld seam acicular ferrite, and help improving the low-temperature flexibility of weld metal.Add Mo, Cr element; Improved the intensity of weld metal on the one hand through solution strengthening, Mo, Cr element have improved the hardenability of weld metal on the other hand, have reduced austenitic phase transition temperature; Promote the formation of low-temperature transformation product low-carbon martensite, improved the obdurability of weld metal.Add further refinement seam organization of a spot of Ti, B element, TiO and TiN that Ti and O, N form are as the forming core particle of acicular ferrite; Promote the formation of weld seam acicular ferrite; And element B is gathered to austenite grain boundary partially, has reduced crystal boundary energy, can suppress the formation of high temperature transformation product.Ti protects B not oxidized in weld seam simultaneously.Adding a spot of Zr element can form ZrO forming core particle with O, impels the formation of weld seam acicular ferrite, and Zr also can generate zirconium nitride with N chemical combination simultaneously, reduces the nomadic nitrogen in the weld seam, improves the toughness of weld seam.S, P, O, N when content is higher, will impel weld metal to produce fire check and cold crack as impurity element, reduce the cracking resistance and the low-temperature flexibility of weld metal, therefore should strict control in weld metal.

Welding wire of the present invention compared with prior art has following characteristics:

1. welding wire of the present invention is controlled impurity contents such as S, P, O, N owing to strict, and has good cracking resistance and low-temperature flexibility.

2. welding wire of the present invention is suitable for the welding of the structural member of postwelding requirement modifier treatment owing to do not contain precipitation strength elements such as V, Nb

2. welding wire of the present invention forms the forming core particle through adding microalloy element Ti, B, Zr and O, impels the formation of weld seam acicular ferrite, and has further improved the toughness of weld metal.

3. welding wire of the present invention adopts Ar+20%CO ₂Mixed gas arc welding connects, the tensile strength R of gained deposited metal _m>=900MPa, low-temperature flexibility A _{KV-50 ℃}>=60J.

4. welding wire of the present invention is applicable to the welding production of the large-scale important structure parts in heavily loaded field such as engineering machinery, coal mine machinery, railroad bridge, autocrane and high-pressure bottle.

The specific embodiment

Below in conjunction with embodiment the present invention is described further.

According to chemical composition scope of the present invention; Adopt whether vaccum sensitive stove (is the commercially available prod; Specification is there there requirement?) smelted three stove welding wire steels (concrete processing step, as: specification requirements such as temperature, time), through forge, rolling, hot candied, copper facing and twine operation such as axle; Be processed into the finished product welding wire of diameter 1.2mm, the chemical composition of welding wire is as shown in table 1.Three kinds of welding wires adopt Ar+20%CO ₂The argon-rich gas shielded welding, the mechanical performance of gained deposited metal is as shown in table 2.

The chemical composition of table 1 embodiment welding wire (mass percent, %)

The mechanical performance of table 2 embodiment welding wire deposited metal

Surplus is Fe and unavoidable impurities in the listed chemical analysis of welding wire in the above-mentioned table 1.

Through experiment, have only S in the welding wire≤0.010, P≤0.010, O≤0.003, N≤0.007, and the microalloy elements such as Ti, B, Zr that add trace could guarantee that weld metal has good cracking resistance and low-temperature flexibility.

Claims

1. a 900MPa level high performance gas is protected welding wire, and it is characterized in that its concrete chemical composition by quality % is: C 0.081; Si 0.68; Mn 1.93; Ni 2.23; Mo 0.52; Cr 0.34; Ti 0.06; B 0.0021; Zr 0.03; S 0.003; P 0.009; O 0.0012; N 0.0054; Surplus is Fe and unavoidable impurities, should adopt Ar+20%CO during this welding wire welding ₂Argon-rich gas shielded welding.

2. a 900MPa level high performance gas is protected welding wire, and it is characterized in that its concrete chemical composition by quality % is: C 0.087, and Si 0.72; Mn 1.78; Ni 2.18; Mo 0.48; Cr 0.35; Ti 0.08; B 0.0032; Zr 0.04; S 0.004; P 0.006; O 0.0009; N 0.0065, and surplus is Fe and unavoidable impurities, should adopt Ar+20%CO during this welding wire welding ₂Argon-rich gas shielded welding.

3. a 900MPa level high performance gas is protected welding wire, and it is characterized in that its concrete chemical composition by quality % is: C 0.093; Si 0.79; Mn 1.86; Ni 2.09; Mo 0.47; Cr 0.31; Ti 0.05; B 0.0036; Zr 0.02; S 0.001; P 0.007; O 0.0018; N 0.0062, and surplus is Fe and unavoidable impurities, should adopt Ar+20%CO during this welding wire welding ₂Argon-rich gas shielded welding.