A welding rod for a damping alloy and its use

Abstract

The application belongs to the technical field of welding materials, and specifically provides a welding rod for damping alloy, which comprises a welding core and a coating, and the coating comprises the following components in percentage of the total mass of the coating: 8-10% of strontium carbonate, 10-18% of fluorite, 5-6% of sodium fluoride, 5-7% of silicon powder, 12-18% of rutile, 2-3% of atomized ferrosilicon, 5-7% of aluminum oxide, 20-21% of electrolytic manganese, 1-2% of yttrium oxide, and the balance is iron powder. The welding rod for damping alloy has good all-position welding process performance and excellent mechanical properties, the average value of deposited metal-20 DEG C KV2 is greater than 80 J, the weld is beautiful, and the chemical composition, mechanical properties and damping performance of the deposited metal can meet the welding requirements of damping steel.

Description

Technical Field

[0001] This invention belongs to the field of welding materials technology, specifically relating to a damping alloy welding electrode and its application. Background Technology

[0002] Materials that can convert mechanical vibration into heat energy dissipation, thereby reducing noise and vibration, are collectively referred to as damping materials. Iron-based damping alloys mainly include Fe-C, Fe-Cr, Fe-Al, and Fe-Mn damping alloys. Fe-C damping alloys are cast iron, a multiphase alloy, inexpensive and easy to produce. However, cast iron has low strength, poor corrosion resistance, and high brittleness, making it difficult to meet the mechanical performance requirements of manufactured components, and its damping performance is relatively low. Fe-Al and Fe-Cr damping alloys are both ferromagnetic damping alloys. While Fe-Al damping alloys have good damping performance and strength, they suffer from significant brittleness. Fe-Cr damping alloys have good damping performance but poor toughness. Fe-Mn damping alloys have good damping performance, good mechanical properties, good machinability, and low cost, making them suitable for widespread, high-volume applications.

[0003] Currently, there is a lack of welding electrodes that are compatible with Fe-Mn damping alloys. Therefore, this invention has developed a welding electrode that is compatible with Fe-Mn damping steel. Summary of the Invention

[0004] The purpose of this invention is to overcome the problem of the lack of matching welding electrodes for Fe-Mn damping alloys in the prior art.

[0005] Therefore, the present invention provides a welding electrode for damping alloys, comprising a core and a coating. The coating comprises the following components by total mass percentage: 8-10% strontium carbonate, 10-18% fluorite, 5-6% sodium fluoride, 5-7% silica powder, 12-18% rutile, 2-3% atomized ferrosilicon, 5-7% aluminum oxide, 20-21% electrolytic manganese, 1-2% yttrium oxide, and the balance being iron powder.

[0006] Specifically, based on the total mass percentage of the welding core, the aforementioned welding core includes the following components: 1.2-2.2% Mn, 21-23% Cr, 11-14% Ni, C≤0.07%, Si≤0.60%, S≤0.03%, P≤0.03%, with the balance being iron and unavoidable impurities.

[0007] Specifically, the mass ratio of the welding core to the flux coating is 7:3.

[0008] Specifically, the outer diameter of the aforementioned welding rod is 6.4-6.6 mm.

[0009] Specifically, based on the total mass percentage of the coating, the coating comprises the following components: 10% strontium carbonate, 18% fluorite, 6% sodium fluoride, 7% silica fume, 18% 98° rutile, 3% 45# atomized ferrosilicon, 7% aluminum oxide, 21% electrolytic manganese, 2% yttrium oxide, and the balance being iron powder.

[0010] Specifically, based on the total mass percentage of the coating, the coating comprises the following components: 9% strontium carbonate, 15% fluorite, 5.5% sodium fluoride, 6% silica fume, 15% 98° rutile, 2.5% 45# atomized ferrosilicon, 6% aluminum oxide, 20.5% electrolytic manganese, 1.5% yttrium oxide, with the balance being iron powder.

[0011] Specifically, based on the total mass percentage of the coating, the coating comprises the following components: 8% strontium carbonate, 10% fluorite, 5% sodium fluoride, 5% silica fume, 12% 98° rutile, 2% 45# atomized ferrosilicon, 5% aluminum oxide, 20% electrolytic manganese, 1% yttrium oxide, and the balance being iron powder.

[0012] The welding electrode provided by this invention can be used for welding damping alloys, and is preferably used for welding Mn17 type damping steel.

[0013] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0014] The damping alloy welding electrode provided by this invention has good all-position welding process performance and excellent mechanical properties. Its weld metal has an average KV2 value of >80J at -20℃, and the weld is aesthetically pleasing. The chemical composition, mechanical properties and damping properties of the weld metal can meet the welding requirements of damping steel. Detailed Implementation

[0015] The technical solutions of the present invention will be clearly and completely described below with reference to embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Although representative embodiments of the present invention have been described in detail, those skilled in the art will understand that various modifications and changes can be made to the present invention without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the embodiments, but should be defined by the appended claims and their equivalents.

[0016] This invention provides a welding electrode for damping alloys, comprising a core and a coating, wherein the mass ratio of the core to the coating is preferably 7:3, and the outer diameter of the electrode is preferably 6.4-6.6 mm.

[0017] The coating comprises the following components by weight percentage: 8-10% strontium carbonate, 10-18% fluorite, 5-6% sodium fluoride, 5-7% silica fume, 12-18% 98° rutile, 2-3% 45# atomized ferrosilicon, 5-7% aluminum oxide, 20-21% electrolytic manganese, 1-2% yttrium oxide, with the remainder being iron powder for filling.

[0018] The design principles of the coating components in the damping steel welding electrode of this invention are as follows:

[0019] Strontium carbonate decomposes at high temperatures to produce CO2, which mainly serves to form slag and gas. When the strontium carbonate content is too low, it cannot provide protection, while when the content is too high, it will increase the spatter of the welding rod. Therefore, the strontium carbonate content should be controlled at 8-10%.

[0020] Fluorite's main component is CaF2, and it mainly plays a role in slag formation, gas generation, and improving the fluidity of molten slag. When the fluorite content is too low, it cannot provide protection, while when its content is too high, it will cause the molten slag of the welding rod to flow and the forming to become poor. Therefore, the fluorite content should be controlled at 10-18%.

[0021] Sodium fluoride plays a role in removing hydrogen and improving fluidity. However, too much sodium fluoride is not conducive to weld formation. The amount added should be controlled at 5-6%.

[0022] The main component of silicon micro powder is SiO2, which plays a role in improving the fluidity of molten slag. When the SiO2 content is too high, it will cause difficulty in slag removal, while when the content is too low, it will result in poor fluidity of the welding electrode slag. Therefore, the present invention controls the silicon micro powder content to 5-7%.

[0023] The main component of 98° rutile is TiO2, which plays a role in calming the molten pool. When the TiO2 content is too high, the impact performance will be poor, while when the content is too low, the welding electrode's process performance will be poor. Therefore, the content of 98° rutile should be controlled at 12-18%.

[0024] 45# atomized ferrosilicon plays a deoxidizing role. When the content of 45# atomized ferrosilicon is too low, the deoxidation is insufficient, resulting in poor impact performance. On the other hand, if the content is too high, the strength will be too high and the performance will be poor. Therefore, the content of 45# atomized ferrosilicon should be controlled at 2-3%.

[0025] Electrolytic manganese plays a role in deoxidation and alloy transition. In this invention, the content of electrolytic manganese is controlled at 20-21%.

[0026] Yttrium oxide plays a role in purifying the weld seam. Since rare earth elements are relatively expensive, the yttrium oxide content is controlled at 1-2%.

[0027] Aluminum oxide is the main component of slag, which can adjust the melting point and viscosity of slag, improve weld formation, facilitate a smooth transition of the weld to the base metal, increase the interface between slag and weld, and give the slag good coverage. When the amount added to the coating is small, the above characteristics cannot be observed. When the amount added is large, the oxygen content in the weld increases, reducing the low-temperature impact toughness of the weld metal. Therefore, the aluminum oxide content should be controlled at 5-7%.

[0028] The welding core comprises the following components by weight percentage: C≤0.07%, Mn 1.2-2.2%, Si≤0.60%, S≤0.03%, P≤0.03%, Cr: 21-23%, Ni: 11-14%, with the balance being iron and unavoidable impurities.

[0029] The design principles for the preferred composition of the core electrode in the damping steel welding electrode of the present invention are as follows:

[0030] Carbon (C) is a solid solution strengthening element that can improve the strength of weld metal and has a significant impact on its toughness. When the C content is low, it can effectively improve the toughness of the weld metal; when the C content is high, the weld metal is more prone to cracking. Therefore, the C content should be reduced as much as possible and controlled to ≤0.07%.

[0031] Mn is the main deoxidizer, which reduces the oxygen content of weld metal, increases the strength and crack resistance of weld metal, improves low-temperature impact toughness, and regulates the fluidity of molten iron. However, as the Mn content increases, segregation will cause hard phases in the microstructure, which will reduce the weld metal's resistance to hydrogen sulfide corrosion. Therefore, this invention controls the Mn content to be between 1.2% and 2.2%.

[0032] Si is the main deoxidizer, and its deoxidation effect is better when combined with Mn. It reduces the oxygen content of the weld metal, improves the low-temperature impact toughness, and regulates the fluidity of molten iron. However, if too much Si is added, the molten iron becomes sticky, the weld strength is too high, and the low-temperature impact toughness is reduced. Therefore, the present invention limits the Si content to ≤0.6%.

[0033] P is an impurity element that severely affects the weld metal's resistance to hydrogen sulfide and reduces its low-temperature impact toughness. S forms sulfide inclusions with elements such as Fe, which can induce pitting corrosion and stress corrosion cracking. P has a strong segregation effect, causing unevenness in the weld metal, especially increasing cold brittleness. Therefore, this invention aims to minimize the content of S and P, limiting the S content to ≤0.03% and the P content to ≤0.03%.

[0034] Ni can improve the low-temperature impact toughness of weld metal, but excessive amounts are expensive. Considering all factors, the content in the core material is controlled at 11-14%.

[0035] Cr is one of the most important alloying elements for improving corrosion resistance. In this invention, the Cr content in the welding core is controlled at 21-23%.

[0036] The effects of the damping alloy welding electrode of the present invention will be studied through specific embodiments below.

[0037] Example 1:

[0038] This embodiment provides a welding electrode for damping alloys, comprising a core and a coating. The coating comprises the following components by weight percentage: 10% strontium carbonate, 18% fluorite, 6% sodium fluoride, 7% silica fume, 18% 98° rutile, 3% 45# atomized ferrosilicon, 7% aluminum oxide, 21% electrolytic manganese, 2% yttrium oxide, with the balance being iron powder. The core comprises the following components by weight percentage: 0.06% C, 2.2% Mn, 0.50% Si, 0.03% S, 0.03% P, 23% Cr, 14% Ni, with the balance being iron and unavoidable impurities.

[0039] The mass ratio of the core to the coating in the welding electrode is 7:3, and the outer diameter of the welding electrode is 6.4 mm.

[0040] The welding electrode prepared in this embodiment can be used for welding Mn17 type damping steel. The chemical composition of the weld metal was tested, and the results are shown in Table 1. The mechanical properties and damping properties of the weld metal were tested, and the results are shown in Table 2.

[0041] Example 2:

[0042] This embodiment provides a welding electrode for damping alloys, comprising a core and a coating. The coating comprises the following components by weight percentage: 9% strontium carbonate, 15% fluorite, 5.5% sodium fluoride, 6% silica fume, 15% 98° rutile, 2.5% 45# atomized ferrosilicon, 6% aluminum oxide, 20.5% electrolytic manganese, 1.5% yttrium oxide, with the balance being iron powder. The core comprises the following components by weight percentage: 0.04% C, 1.8% Mn, 0.40% Si, 0.008% S, ≤0.006% P, 22% Cr, 12% Ni, with the balance being iron and unavoidable impurities.

[0043] The mass ratio of the core to the coating in the welding electrode is 7:3, and the outer diameter of the welding electrode is 6.5 mm.

[0044] The welding electrode prepared in this embodiment can be used for welding Mn17 type damping steel. The chemical composition of the weld metal was tested, and the results are shown in Table 1. The mechanical properties and damping properties of the weld metal were tested, and the results are shown in Table 2.

[0045] Example 3:

[0046] This embodiment provides a welding electrode for damping alloys, comprising a core and a coating. The coating comprises the following components by weight percentage: 8% strontium carbonate, 10% fluorite, 5% sodium fluoride, 5% silica fume, 12% 98° rutile, 2% 45# atomized ferrosilicon, 5% aluminum oxide, 20% electrolytic manganese, 1% yttrium oxide, with the balance being iron powder. The core comprises the following components by weight percentage: 0.07% C, 1.2% Mn, 0.60% Si, 0.01% S, 0.02% P, 21% Cr, 11% Ni, with the balance being iron and unavoidable impurities.

[0047] The mass ratio of the core to the coating in the welding electrode is 7:3, and the outer diameter of the welding electrode is 6.6 mm.

[0048] The welding electrode prepared in this embodiment can be used for welding Mn17 type damping steel. The chemical composition of the weld metal was tested, and the results are shown in Table 1. The mechanical properties and damping properties of the weld metal were tested, and the results are shown in Table 2.

[0049] Table 1: Chemical composition (%) of electrode deposited metal

[0050] serial number C Si Mn S P Ni Cr Example 1 0.051 0.32 8.0 0.024 0.026 13.9 22.9 Example 2 0.032 0.29 7.5 0.006 0.007 11.9 21.7 Example 3 0.063 0.38 7.1 0.010 0.015 10.8 20.8

[0051] Table 2: Mechanical and Damping Properties of Electrode Deposited Metal

[0052]

[0053]

[0054] As shown in Tables 1-2, the chemical composition, mechanical properties, and damping properties of the weld metal of the damping alloy welding electrode provided by this invention can all meet the welding requirements of damping steel.

[0055] The above examples are merely illustrative of the present invention and do not constitute a limitation on the scope of protection of the present invention. All designs that are the same as or similar to the present invention are within the scope of protection of the present invention.

Claims

1. A welding electrode for damping alloys, comprising a core and a coating, characterized in that, The coating comprises, by weight percentage, the following components: 8-10% strontium carbonate, 10-18% fluorite, 5-6% sodium fluoride, 5-7% silica fume, 12-18% rutile, 2-3% atomized ferrosilicon, 5-7% aluminum oxide, 20-21% electrolytic manganese, 1-2% yttrium oxide, with the balance being iron powder; the core comprises, by weight percentage, the following components: 1.2-2.2% Mn, 21-23% Cr, 11-14% Ni, C≤0.07%, Si≤0.60%, S≤0.03%, P≤0.03%, with the balance being iron and unavoidable impurities.

2. The welding electrode for damping alloys as described in claim 1, characterized in that: The mass ratio of the welding core to the flux coating is 7:

3.

3. The welding electrode for damping alloys as described in claim 1, characterized in that: The outer diameter of the welding electrode is 6.4-6.6 mm.

4. The welding electrode for damping alloys as described in claim 1, characterized in that, The coating comprises the following components by weight percentage: 10% strontium carbonate, 18% fluorite, 6% sodium fluoride, 7% silica fume, 18% 98° rutile, 3% 45# atomized ferrosilicon, 7% aluminum oxide, 21% electrolytic manganese, 2% yttrium oxide, and the balance being iron powder.

5. The welding electrode for damping alloys as described in claim 1, characterized in that, The coating comprises the following components by weight percentage: 9% strontium carbonate, 15% fluorite, 5.5% sodium fluoride, 6% silica fume, 15% 98° rutile, 2.5% 45# atomized ferrosilicon, 6% aluminum oxide, 20.5% electrolytic manganese, 1.5% yttrium oxide, with the balance being iron powder.

6. The welding electrode for damping alloys as described in claim 1, characterized in that, The coating comprises the following components by weight percentage: 8% strontium carbonate, 10% fluorite, 5% sodium fluoride, 5% silica fume, 12% 98° rutile, 2% 45# atomized ferrosilicon, 5% aluminum oxide, 20% electrolytic manganese, 1% yttrium oxide, with the balance being iron powder.

7. The application of the damping alloy welding electrode as described in any one of claims 1-6, characterized in that: The welding rod is used for welding Mn17 type damping steel.

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