Welding material with low weld porosity and application thereof

Abstract

The invention belongs to the field of corrosion-resistant steel welding materials for railway vehicles, and particularly relates to a welding material with low weld porosity and application of the welding material. The invention provides a high-corrosion-resistance argon-rich gas shielded welding material with low weld porosity for railway vehicles. The high-corrosion-resistance argon-rich gas shielded welding material comprises the following elements in percentage by mass: 0 to 0.05 percent of C, 0.65 to 0.80 percent of Si, 1.20 to 1.50 percent of Mn, 1.70 to 2.50 percent of Cr, 1.50 to 2.00 percent of Ni, 0 to 0.15 percent of Cu, 0 to 0.1 percent of Mo, 0.02 to 0.03 percent of Ti, 0 to 0.05 percent of Ca, 0 to 0.03 percent of Mg, 0.01 to 0.03 percent of Y, 0 to 0.001 percent of B, less than or equal to 0.004 percent of O, less than or equal to 0.006 percent of N and the balance of Fe and other inevitable impurities.

Description

Technical Field

[0001] The invention belongs to the field of corrosion-resistant steel welding materials for railway vehicles, and in particular relates to a welding material with low weld porosity and application thereof. Background Art

[0002] With the development of steel smelting technology and the continuous improvement of the requirements for high speed, heavy load and low cost of railway vehicles, the main materials of railway vehicle bodies have undergone a transformation from ordinary low-strength carbon steel to low-strength atmospheric corrosion-resistant steel and high-strength atmospheric corrosion-resistant steel. At present, Q350EWR1-Q450EWR1 grade high corrosion-resistant steel with high corrosion resistance has been widely developed in the field of railway vehicles. Its practical application is generally mainly welded structural parts. Since the railway vehicle itself needs to bear dynamic loads, it puts forward higher requirements on the crack resistance of the joint. Therefore, the gas-shielded solid welding wire and submerged arc welding wire with good weld metal crack resistance are generally used in the welding process. In particular, argon-rich gas-shielded solid welding wire has less spatter during welding, stable droplet transition, and excellent weld impact performance. It has been widely used in flat-position welded fillet joints and butt joints of high-corrosion-resistant steel. However, the welding pool of argon-rich gas-shielded welding wire is small and the weld cooling speed is fast. The gas generated by metallurgical reaction in the molten pool is easy to overflow and remain in the weld before it can form pore defects. To ensure a service life of 25 years, high corrosion-resistant steel has added corrosion-resistant elements such as 3-5.5wt.% Cr and 0.1-0.65wt.% Ni. To ensure that the weld metal matches the base material, the welding wire also has added a high proportion of alloy elements such as Cr and Ni. In the actual welding process, a large amount of alloy elements are melted and transferred to the weld through the welding wire, the viscosity of the welding pool increases, and the fluidity decreases. This makes the high porosity problem of the argon-rich gas protected weld of high corrosion-resistant steel more prominent, the flaw detection pass rate is low, and the risk of weld repair is extremely high. Summary of the invention

[0003] To solve the above problems, the present invention provides a welding material, comprising the following elements in percentage by mass: C: 0-0.05, Si: 0.65-0.80, Mn: 1.20-1.50, Cr: 1.70-2.50, Ni: 1.50-2.00, Cu: 0-0.15, Mo: 0-0.1, Ti: 0.02-0.03, Ca: 0-0.05, Mg: 0-0.03, Y: 0.01-0.03, B: 0-0.001, O: ≤0.004, N: ≤0.006, and the balance is Fe and other inevitable impurities.

[0004] The present invention also provides a welding wire, the composition of which includes the above welding material.

[0005] Furthermore, the diameter of the welding wire is 1.2 mm, and the thickness of the copper plating layer on the surface of the welding wire is 0.19-0.22 μm.

[0006] Furthermore, the welding wire contains at least three of Ti, Ca, Mg, Y and B; the chemical composition calculated by weight percentage satisfies: 0.02≤α≤0.07, 0.04≤γ≤0.60, wherein: α=(Ti+1 / 2Ca+1 / 2Mg+3Y) / (Si+Mn); γ=Ni+7Cu+15Mo-Cr-Si.

[0007] The invention also provides application of the welding material in argon-rich gas shielded welding.

[0008] The present invention has the following beneficial effects:

[0009] The present invention limits the content of each chemical element in the welding wire, puts forward innovative technical requirements, and accurately controls the addition amount of some key elements to play the key regulating role of element ratio on the metallurgical quality, corrosion resistance, mechanical properties and other comprehensive properties of the argon-rich gas shielded welding weld. The argon-rich gas shielded welding wire dedicated to Q350EWR1-Q450EWR1 high corrosion-resistant steel is obtained, with a porosity of less than 1% and a relative corrosion rate of less than 7.4% with high corrosion-resistant steel under the process conditions of 10-25kJ / cm heat input, and an impact toughness of not less than 75J at -40℃. The welding wire can be widely used in the welding of fillet joints and butt joints of flat-position welding of high corrosion-resistant steel. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0011] Figure 1 The morphology of the wire rod for argon-rich gas shielded welding wire of the embodiment and the comparative example;

[0012] Figure 2 Appearance morphology and radiographic flaw detection results of the argon-rich gas shielded welding welds of the embodiments and comparative examples;

[0013] Figure 3 The macroscopic morphology of the argon-rich gas welds of the embodiments and comparative examples after 48h and 72h of accelerated corrosion test. DETAILED DESCRIPTION

[0014] Now, various exemplary embodiments of the present invention are described in detail. The methods in the examples are conventional methods unless otherwise specified, and the reagents used are conventional commercially available reagents or reagents prepared by conventional methods unless otherwise specified. This detailed description should not be considered as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, features and embodiments of the present invention.

[0015] It should be understood that the terms described in the present invention are only for describing a particular embodiment and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. The intermediate value in any stated value or stated range, and each smaller range between any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0016] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0017] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present invention description and examples are exemplary only.

[0018] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0019] Examples 1-7 and Comparative Examples 1-3

[0020] The invention provides a high corrosion-resistant argon-rich gas shielded welding wire and wire rod for railway vehicles with low weld porosity, comprising the following elements in percentage by mass: C: 0-0.05, Si: 0.65-0.80, Mn: 1.20-1.50, Cr: 1.70-2.50, Ni: 1.50-2.00, Cu: 0-0.15, Mo: 0-0.1, Ti: 0.02-0.03, Ca: 0-0.05, Mg: 0-0.03, Y: 0.01-0.03, B: 0-0.001, O: ≤0.004, N: ≤0.006, and the balance is Fe and other inevitable impurities.

[0021] The high corrosion-resistant argon-rich gas welding wire and wire rod for railway vehicles with low weld porosity adopts 80% to 95% Ar and CO 2 and / or 2 The welding is performed with a mixed gas of 5% to 20%, and the welding wire contains 3 or 4 of Ti, Ca, Mg, Y, and B. The mass percentage of each element satisfies the following conditions: 0.02≤α≤0.07, wherein α=(Ti+1 / 2Ca+1 / 2Mg+3Y) / (Si+Mn); 0.04≤γ≤0.60, wherein γ=Ni+7Cu+15Mo-Cr-Si;

[0022] In terms of mass percentage, the present invention includes C: 0-0.05wt.%. C is one of the alloy elements with the strongest strengthening effect. Adding a certain amount of C to the steel is beneficial to improving the drawing performance of the welding wire steel and reducing cracks on the surface of the wire rod. However, when excessive C is added to the welding wire, the welding performance will be deteriorated, and the plasticity and toughness of the weld will be significantly reduced.

[0023] In terms of mass percentage, the present invention includes Si: 0.65-0.80wt.%, Si: Si plays a major role in strong deoxidation in the weld, reduces the viscosity of the welding molten pool, improves the fluidity of the molten pool, and can improve the strength and toughness of the weld within a certain range. At the same time, the Si element can also form a Si-rich protective film on the surface of the steel, refine α-FeOOH, and thus reduce the corrosion rate of the steel; but when Si is excessive, coarse M / A components and side plate ferrite will appear in the weld.

[0024] In terms of mass percentage, the present invention includes Mn: 1.2-1.5wt.%. The main role of Mn in the weld is similar to that of Si, which plays a deoxidizing role. It can also increase the width and depth of the molten pool with Si. In addition, Mn can also significantly reduce the phase change start temperature and refine the structure of the weld. However, the increase in Mn content will increase the segregation inside the steel plate and affect the drawing performance of the welding wire steel rod.

[0025] In terms of mass percentage, the present invention includes Cr: 1.70-2.50wt.%. In the present invention, the most important function of Cr is to improve the weather resistance of the weld metal. With the addition of Cr element, a dense passivation film can be formed on the surface of the weld metal, which significantly improves the atmospheric corrosion resistance, and with the increase of Cr content, the corrosion resistance continues to improve; but too high Cr content will have an adverse effect on weldability, and coarse M / A components and side plate ferrite are easily generated in the weld structure, reducing the toughness of the weld.

[0026] In terms of mass percentage, the present invention includes Ni: 1.50-2.00wt.%, and adding Ni to the weld is also conducive to forming a stable and dense rust layer on the surface of the steel material, and can also improve the low-temperature toughness of the steel plate, greatly improve the low-temperature toughness of the weld metal, and effectively prevent the cracking caused by the hot brittleness of Cu. However, adding too much Ni will significantly increase the viscosity of the molten pool, reduce fluidity, and deteriorate the metallurgical quality of the weld. At the same time, adding a large amount of Ni elements will significantly increase the cost.

[0027] In terms of mass percentage, the present invention includes Cu: 0-0.15wt.%. The increase in Ni content in the weld can also significantly improve the corrosion resistance. At the same time, a certain amount of Cu addition is also conducive to the formation of ε-Cu in the weld, thereby improving the strength of the weld. However, if the Cu content is too high, brittle cracks will occur in the steel plate, affecting the quality of the wire rod and the welding wire. A high Cu content in the weld will increase the crack sensitivity. Considering that copper plating on the surface of the welding wire will transition the Cu element to the weld, the Cu content added to the welding wire is 0-0.15wt.%.

[0028] In terms of mass percentage, the present invention includes Mo: 0-0.10wt.%. Appropriate addition of Mo element to the weld can improve the rust layer structure, increase the density of the rust layer with Si and Ni, and improve the atmospheric corrosion resistance. At the same time, Mo can expand the bainite area and refine the weld structure, but too high Mo content will cause high-density hard and brittle phase M / A components to be generated in the argon-rich gas welding weld.

[0029] In terms of mass percentage, the present invention includes Ti: 0.02-0.03wt.%, the main function of Ti in the weld is deoxidation, and its ability to combine with oxygen is stronger than that of Mn and Si, which is beneficial to protecting the transition of Si and Mn into the weld, and at the same time, 0.1-0.3μm Ti oxide is an effective nucleation site for acicular ferrite, but when the Ti content increases, the size of the inclusions will increase. In welds with high Ti content, large-sized inclusions often appear, which increases crack sensitivity. At the same time, large-sized inclusions are also strong pitting corrosion areas, which can easily destroy the dense oxide film formed on the surface of the weld metal by elements such as Cr and Ni, and significantly reduce corrosion resistance.

[0030] In terms of mass percentage, the present invention includes Ca: 0-0.05wt.%. Ca is also a strong deoxidizing element. In the welding molten pool reaction, it can generate calcium salts with compounds with higher melting points, reduce the viscosity of the welding molten pool, and improve the fluidity of the molten pool. The addition of Ca can also denature the inclusions, and significantly reduce the number of inclusions in the weld. At the same time, the addition of Ca element to the welding wire can also reduce the rust liquid flying phenomenon in welding. However, excessive addition of Ca element will cause the molten pool to react violently, which is not conducive to obtaining excellent weld metallurgical quality.

[0031] In terms of mass percentage, the present invention includes Mg: 0-0.03wt.%, which is also a strong deoxidizing element. It reacts with oxygen to form Mg oxides that can pin the original austenite grain boundaries and significantly reduce the size of austenite grains. At the same time, through Mg treatment, micron-level magnesium oxide and sulfide composite inclusions can be formed, the size and shape of the inclusions can be regulated, and needle-shaped ferrite can be induced to nucleate on the inclusions. However, when the Mg content is too high, it is easy to form a low-melting point eutectic structure with other metals, and crystal cracks are easy to form in the weld.

[0032] In terms of mass percentage, the present invention includes Y (yttrium): 0.01-0.03wt.%. The transition of metal Y to the weld can improve the fluidity of the weld molten pool, accelerate the overflow of pores, and reduce the porosity. At the same time, the addition of Y can also react with oxygen and nitrogen to purify the weld. However, the large amount of Y added will cause it to precipitate along the grain boundary, increase the brittleness of the grain boundary, and is not conducive to obtaining high weld toughness.

[0033] In terms of mass percentage, the present invention includes B: 0-0.001wt.%. The B element can promote the movement and recrystallization of grain boundaries, making the grain boundaries smoother, which is beneficial to improving the weld morphology and reducing welding defects. It can also act in combination with Mo to refine the weld structure. However, when the B content increases, the hardenability of the weld metal will be improved. When the content is too high, the joint hardness and welding crack sensitivity will be significantly increased.

[0034] In terms of mass percentage, the present invention strictly controls the O content in the welding wire to be no higher than 0.004wt.%, and the N content to be no higher than 0.006wt.%.

[0035] In the present invention, the mass percentage of each element in the high corrosion-resistant argon-rich gas shielded welding wire and wire rod for railway vehicles with low weld porosity meets the following conditions: 0.02≤α≤0.07, wherein α=(Ti+1 / 2Ca+1 / 2Mg+3Y) / (Si+Mn); 0.04≤γ≤0.60, wherein γ=Ni+7Cu+15Mo-Cr-Si;

[0036] For argon-rich gas shielded welding, the actual welding process has a small molten pool volume and a fast cooling rate. The gas generated in the metallurgical reaction stage of welding is easy to overflow and form pores before it has time. Especially in the welding wire for corrosion-resistant steel containing high Cr and high Ni, the problem of pores in the weld is more prominent due to the increase in the viscosity of the molten pool, and the porosity generally reaches more than 15%. In the present invention, by adding Ca, Y, and Si elements, the viscosity of the molten pool can be significantly reduced and the fluidity of the molten pool can be improved; at the same time, the ratio α of Ti, Ca, Mg, Y to Si and Mn is regulated to be 0.02-0.07, which, on the one hand, increases the volume of the molten pool, reduces the cooling rate of the liquid metal in the weld, and is conducive to the overflow of pores; on the other hand, the type and size of the inclusions are regulated to increase the number of acicular ferrite nucleation sites and avoid the occurrence of high-density and large-sized inclusions.

[0037] In addition, the present invention regulates the element ratio γ between Ni, Cu, Mo, Cr and Si at 0.04-0.6. The addition of the above elements can significantly increase the corrosion resistance of the weld metal, but the increase of Cr and Si can easily lead to the appearance of coarse side plate ferrite and hard phase M / A components in the weld structure. By regulating the ratio between Ni, Cu, Mo and Cr, Si, the starting temperature of the phase transformation from austenite to ferrite is reduced. On the basis of increasing the number of acicular ferrite nucleation sites by the above regulation formula α, the nucleation of acicular ferrite rather than granular bainite is promoted, the weld structure is significantly refined, and the weld toughness is improved.

[0038] In order to further illustrate the present invention, the highly corrosion-resistant argon-rich gas shielded welding wire and wire rod with low weld porosity for railway vehicles provided by the present invention are described in detail below in conjunction with the accompanying drawings and embodiments, but they should not be understood as limiting the scope of protection of the present invention.

[0039] Seven furnaces of welding wire steel of the embodiment of the present invention and three furnaces of welding wire steel of the comparative example were refined in a 75kg vacuum induction furnace, wherein the element ratio of the welding wire steel of the embodiment of the present invention meets the requirements of the present invention. The welding wire steel of the embodiment and the comparative example were melted and cast in sequence according to a certain element composition ratio to obtain a cast alloy billet, and the composition of the welding wire steel of the embodiment and the comparative example was detected according to GB / T4336 "Spark Source Atomic Emission Spectroscopy Analysis Method for Carbon Steel and Medium and Low Alloy Steel (Conventional Method)", and the specific chemical composition is shown in Table 1.

[0040] Table 1 Chemical composition of welding wire steel of Examples 1 to 7 and Comparative Examples 1 to 3 (wt.%, balance Fe)

[0041] serial number C Si Mn P S Cr Ni Cu Mo Ti Ca Mg B Y V O N α γ Example 1 0.04 0.69 1.35 0.007 0.005 1.85 1.85 0.05 0.04 0.024 0 0.012 0.0009 0.015 - 0.004 0.005 0.037 0.26 Example 2 0.03 0.66 1.42 0.011 0.004 2.14 1.94 0.14 0.03 0.025 0.015 0 0 0.017 - 0.003 0.006 0.040 0.57 Example 3 0.05 0.78 1.26 0.009 0.004 2.34 1.85 0.1 0.07 0.027 0 0.023 0.0007 0.027 - 0.004 0.006 0.059 0.48 Example 4 0.03 0.68 1.37 0.009 0.005 1.97 1.89 0.12 0 0.021 0 0.026 0 0.018 - 0.003 0.005 0.043 0.08 Example 5 0.04 0.67 1.29 0.012 0.005 1.89 1.67 0.09 0.05 0.028 0.036 0.016 0 0.018 - 0.004 0.005 0.055 0.49 Example 6 0.05 0.78 1.44 0.008 0.003 1.96 1.98 0.12 0 0.029 0 0 0.005 0.025 - 0.003 0.006 0.047 0.08 Example 7 0.04 0.71 1.48 0.009 0.005 2.41 1.61 0.13 0.06 0.022 0.025 0 0.007 0.019 - 0.004 0.006 0.042 0.30 Comparative Example 1 0.01 0.51 0.89 0.011 0.004 1.35 3.50 0.25 - 0.04 - - 0.004 - - 0.004 0.005 0.029 3.39 Comparative Example 2 0.06 0.60 0.57 0.007 0.005 1.0 3.20 0.45 0.35 0.10 - - - - - 0.003 0.006 0.086 10 Comparative Example 3 0.08 0.58 0.75 0.009 0.004 1.30 4.0 0.25 - 0.11 - - - - 0.03 0.004 0.006 0.083 3.87

[0042] Performance measurement and result analysis

[0043] Forging welding wire steel billet into a cross section of 50x50mm 2The billet is kept at 1100-1140℃ for 3h, and then dephosphorized at 1020-1050℃, and rolled in multiple passes at 880-920℃, and sized and wire-laying is performed at 800-820℃. Then, the wire rod with a diameter of φ5.5mm is slowly cooled in a heat preservation cover, and the slow cooling temperature range is 740-465℃, and the slow cooling time is 630-670s. The specific welding wire steel wire rod rolling process of the embodiment and the comparative example is shown in Table 2 below. Finally, the wire rod is processed into φ1.2mm welding wire through the process of pickling, borax treatment, rough drawing (φ5.5mm→φ2.55mm), primary fine drawing (φ2.55mm→φ1.25mm), secondary fine drawing (φ1.25mm→φ1.175mm) and copper plating. Figure 1 The morphology of the wire rods after rolling of Example 5 and Comparative Example 3 was observed. The surface of the wire rods of the example was smooth, while the surface of the wire rods in the comparative example had cracks and warping problems, which led to multiple wire breakage problems in the subsequent wire drawing process of the wire rods, seriously affecting the drawing efficiency and the quality of the finished welding wire.

[0044] Table 2 Welding steel wire rod rolling process parameters of Examples 1 to 7 and Comparative Examples 1 to 3

[0045]

[0046] The welding wires prepared in Examples 1 to 7 and Comparative Examples 1 to 3 were subjected to welding tests of typical butt joints. The specific welding process parameters are shown in Table 3. The welding test plate was made of Q450EWR1 corrosion-resistant steel with a thickness of 16 mm. The steel plate had a yield strength of 485 MPa, a tensile strength of 605 MPa, an elongation of 21%, and a low-temperature impact of -40°C of 205 J.

[0047] Table 3 Process parameters of argon-rich gas shielded welding of welding wire in Examples 1 to 7 and Comparative Examples 1 to 3

[0048]

[0049] After welding, the specimens were inspected for appearance and the welds were inspected using X-rays. The macroscopic morphology and X-ray inspection photos of the joints of Example 2 and Comparative Example 1 are shown in Figure 1 The welding wire provided by the present invention has excellent weld formation, and no obvious defects are found inside under irradiation; while the weld of the comparative wire has a concave-convex surface and poor formation, and pores of different sizes can be found under irradiation. Samples were taken from the defect-free area, and the chemical composition of the weld metals of the embodiment and the comparative example was tested in accordance with GB / T 4336 "Spark Source Atomic Emission Spectrometric Analysis Method for Carbon Steel and Medium and Low Alloy Steel (Conventional Method)", and the test results are shown in Table 4.

[0050] Table 4 Chemical composition of weld metal after argon-enriched gas shielded welding of Examples 1 to 7 and Comparative Examples 1 to 3 (wt.%, remainder Fe)

[0051] serial number C Si Mn P S Cr Ni Cu Mo Ti Ca Mg B Y V O N Example 1 0.03 0.61 1.22 0.009 0.004 1.83 1.84 0.17 0.04 0.010 0 0.005 0.0009 0.004 - 0.006 0.008 Example 2 0.03 0.60 1.34 0.010 0.005 2.11 1.93 0.21 0.03 0.008 0.005 0 0 0.006 - 0.007 0.009 Example 3 0.04 0.71 1.19 0.009 0.005 2.30 1.82 0.24 0.07 0.011 0 0.009 0.0007 0.009 - 0.007 0.008 Example 4 0.03 0.59 1.21 0.009 0.003 1.95 1.87 0.23 0 0.009 0 0.010 0 0.008 - 0.008 0.009 Example 5 0.04 0.60 1.16 0.008 0.004 1.85 1.67 0.21 0.05 0.011 0.012 0.006 0 0.006 - 0.007 0.009 Example 6 0.03 0.71 1.35 0.010 0.005 1.92 1.97 0.26 0 0.010 0 0 0.005 0.007 - 0.007 0.008 Example 7 0.04 0.62 1.35 0.009 0.005 2.38 1.60 0.27 0.06 0.008 0.007 0 0.007 0.007 - 0.007 0.007 Comparative Example 1 0.02 0.39 0.80 0.009 0.004 1.27 3.45 0.38 - 0.02 - - 0.004 - - 0.006 0.009 Comparative Example 2 0.04 0.48 0.48 0.008 0.004 0.95 3.18 0.56 0.34 0.05 - - - - - 0.008 0.008 Comparative Example 3 0.06 0.46 0.60 0.007 0.005 1.21 3.98 0.37 - 0.04 - - - - 0.025 0.011 0.009

[0052] The welded joints provided in Examples 1 to 7 and Comparative Examples 1 to 3 were sampled, and tensile specimens of the entire weld metal were taken along the weld direction according to GB / T228.1 standard to complete the strength test. Weld impact specimens were taken according to GB / T 2650 standard, and a total of three specimens were tested and the average value was taken. The test results of the mechanical properties of the weld metal are shown in Table 5. The results show that the weld metal of the embodiment can achieve both strength and toughness of the weld metal, while the comparative example has the problem of high strength or low toughness.

[0053] Table 5 Mechanical properties test results of weld metal after argon-rich gas shielded welding of Examples 1 to 7 and Comparative Examples 1 to 3

[0054]

[0055] The weld metal samples provided in Examples 1 to 7 and Comparative Examples 1 to 3 were sampled and the samples were quenched with 0.01 mol / L NaHSO 3 The solution simulated the industrial atmospheric environment, and the accelerated corrosion test of Q450EWR1 base metal and weld metal was carried out in a weekly immersion accelerated corrosion test box for 120 hours, and the relative corrosion rates of the base metal and the weld metals of the embodiment and the comparative example were calculated (relative corrosion rate = |base metal weight loss - weld metal weight loss / base metal weight loss × 100% |) to evaluate the atmospheric corrosion resistance of the base metal and the weld metal. The test results after 120 hours are shown in Table 6. The results show that the weld metals of the embodiments have a relative corrosion rate of less than 10% with the Q450EWR1 base metal, which meets the standard requirements and can match the corrosion performance of the base metal, while the relative corrosion rate of the comparative welding wire with the base metal is higher than 13%, indicating that the corrosion performance is poor. In addition, the accelerated corrosion coupons of Example 3 and Comparative Example 2 were observed for 48h and 72h, respectively. The surface rust layer of the Example coupon was more uniform, and no obvious corrosion pits were present, while the surface of the Comparative Example coupon had a large number of obvious depressions and poor uniformity, indicating that there was obvious corrosion non-uniformity in the solution, which was not conducive to obtaining high corrosion resistance.

[0056] Table 6 Comparison results of corrosion weight loss of weld metal and parent metal in argon-rich gas shielded welding of Examples 1 to 7 and Comparative Examples 1 to 3

[0057]

[0058] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A welding material, characterized in that: Including the following elements in mass percentage: C: 0-0.05, Si: 0.65-0.80, Mn: 1.20-1.50, Cr: 1.70-2.50, Ni: 1.50-2.00, Cu: 0-0.15, Mo: 0-0.1, Ti: 0.02-0.03, Ca: 0-0.05, Mg: 0-0.03, Y: 0.01-0.03, B: 0-0.001, O: ≤0.004, N: ≤0.006, the balance is Fe and other inevitable impurities.

2. A welding wire, characterized in that: The composition comprises the welding material as claimed in claim 1.

3. The welding wire according to claim 2, characterized in that The diameter of the welding wire is 1.2 mm, and the thickness of the copper plating layer on the surface of the welding wire is 0.19-0.22 μm.

4. The welding wire according to claim 2, characterized in that The welding wire contains at least three of Ti, Ca, Mg, Y and B; the chemical composition calculated by weight percentage satisfies: 0.02≤α≤0.07, 0.04≤γ≤0.60, wherein: α=(Ti+1 / 2Ca+1 / 2Mg+3Y) / (Si+Mn); γ=Ni+7Cu+15Mo-Cr-Si.

5. Use of the welding material as claimed in claim 1 in argon-rich gas shielded welding.

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