Nickel-chromium-molybdenum alloy welding rod and preparation method and use method thereof

Abstract

The invention belongs to the technical field of welding materials, and particularly relates to a nickel-chromium-molybdenum alloy welding rod and a preparing method and using method thereof.The welding rod comprises a core wire and a coating, and cladding metal of the welding rod comprises, by weight, 0.03%-0.05% of C, 0.4%-0.7% of Mn, 15.5%-15.8% of Cr, 5.7%-5.9% of Ni, 0.8%-0.95% of Mo, smaller than or equal to 0.30% of Si, smaller than or equal to 0.020% of S, smaller than or equal to 0.030% of P and the balance Fe and inevitable impurities. According to the welding rod, the welding performance and various mechanical properties of the welding rod can be properly adjusted by adjusting the content of nickel, chromium and molybdenum, so that the welding rod can meet various heat treatment modes after welding, and the adaptability and universality of the welding rod are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of welding materials, and specifically relates to a nickel-chromium-molybdenum alloy welding rod and a preparation method and a use method thereof. Background Art

[0002] Special equipment such as nuclear power and aviation equipment are generally assembled by welding multiple in-core components. Defects in certain components such as valves produced during the casting process also need to be repaired by welding. In addition to ensuring that the mechanical properties meet the original design requirements, the composition and color of the parent material also need to be homogenized. Therefore, welding materials are required to be of many types, highly professional, and have high requirements.

[0003] Special equipment components need to be heat treated after casting to eliminate their stress. After being repaired by welding, due to their complex composition and structure, they still need to be heat treated like the parent material. There are different heat treatment methods according to the different castings and defects to be repaired by welding. The heat treatment specifications include but are not limited to tempering, quenching, quenching + tempering and solid solution. Different heat treatment methods have different requirements for welding rods. If the welding rod and the heat treatment method cannot match, the mechanical effect of the welding powder formed by the welding rod under the heat treatment conditions will not meet the actual requirements, which will cause the welding to be easily worn, cracks will be generated, and the mechanical properties of the weldment will be poor.

[0004] In the prior art, for example, a Chinese patent with publication number CN112475660A discloses a wear-resistant cladding electrode and a preparation method thereof. By innovating and limiting the main components of the electrode coating and the welding core, the electrode can have good crack resistance, certain hardness and wear resistance under the heat treatment process of 913℃*8h air cooling + 885℃*8h liquid quenching + 676℃*5h furnace cooling.

[0005] However, most of the current welding rods can only meet the heat treatment methods under certain specific conditions, and have great limitations in application in manufacturing production. Therefore, it is necessary to develop a welding rod that can meet multiple heat treatment methods. Summary of the invention

[0006] In view of the fact that most of the existing welding rods mentioned in the above background technology can only meet the heat treatment method under certain specific conditions, the present invention improves the welding performance of the welding rod by controlling the content of nickel, chromium and molybdenum in the welding rod, ensuring that it can meet a variety of post-welding heat treatment methods.

[0007] The specific technical solutions of the present invention are as follows:

[0008] A nickel-chromium-molybdenum alloy welding rod, the welding rod comprises a welding core and a coating, the coating comprises the following components in parts by weight: 15.0-25.0 parts of carbonate; 25.0-35.0 parts of titanium dioxide; 4-8 parts of fluoride; 2.0-5.0 parts of silicon oxide; 2.0-5.0 parts of electrolytic manganese; 8.0-14.0 parts of metallic chromium; 7.0-12.0 parts of metallic nickel; 0.5-1.5 parts of chromium nitride; 2.5-5.0 parts of metallic molybdenum; and 0.5-1.2 parts of CMC.

[0009] Furthermore, the welding core comprises the following components in weight: C: ≤0.030 parts; Mn: 1.50-2.20 parts; Si: ≤0.35 parts; S: ≤0.015 parts; P: ≤0.022 parts; Cr: 16.0-17.5 parts; Ni: ≤1.0; Mo: ≤0.50 parts; Cu: ≤0.50 parts; N: ≤0.050 parts; and the balance is Fe.

[0010] Furthermore, the mass ratio of the welding core to the coating is 65% for the welding core and 35% for the coating.

[0011] Furthermore, the cladding metal of the welding rod includes the following components in weight percentage: C 0.03-0.05%, Mn 0.4-0.7%, Cr 15.5-15.8%, Ni 5.7-5.9%, Mo 0.8-0.95%, Si≤0.30%, S≤0.020%, P≤0.030%, and the balance is Fe and inevitable impurities.

[0012] The present invention also provides a method for preparing a nickel-chromium-molybdenum alloy welding rod, comprising the following steps: (1) mixing the components of the coating raw material uniformly according to a proportion, and then adding an adhesive to obtain a mixture; (2) adding the mixture prepared in step (1) and a welding core to a pressure coating machine, uniformly preparing and forming the surface of the welding core, and then baking at low temperature and high temperature to obtain the welding rod.

[0013] Furthermore, the binder is potassium sodium water glass, and the ratio of potassium to sodium is 3:1; the weight ratio of the binder to the drug coating raw material is 0.18-0.21:1; the temperature of the low-temperature baking is 80-120°C, and the temperature of the high-temperature baking is 360°C.

[0014] The present invention also provides a method for using a nickel-chromium-molybdenum alloy welding rod, comprising the following steps:

[0015] S1. Welding: First bake and heat the welding rod and the workpiece to be welded, and after heating, set the welding parameters for welding;

[0016] S2. Heat treatment: The welded workpiece is heat treated to obtain a complete welded part.

[0017] Furthermore, in step S1, the electrode baking temperature is 350°C, the baking time is 1h, and the workpiece heating temperature is 150°C; the welding parameters include: welding current 150-160A, welding voltage 22V, interpass temperature less than or equal to 110°C, and welding line energy 11KJ / cm.

[0018] Further, the heat treatment in step S2 is any one of the following three methods: a. keeping at 580°C for 4 hours and then air cooling to room temperature; b. keeping at 590°C for 8 hours and then cooling to 300°C with the furnace and then air cooling to room temperature; c. keeping at 1030°C for 1 hour and then air cooling to 590°C and then keeping for another 8 hours, then cooling to 300°C with the furnace and then air cooling to room temperature.

[0019] Beneficial effects of the present invention:

[0020] (1) The welding rod of the present invention can adjust the welding performance and various mechanical properties of the welding rod by adjusting the content of nickel, chromium and molybdenum, so that it can comply with various post-welding heat treatment methods, thereby improving the adaptability and versatility of the welding rod.

[0021] (2) During welding, the welding rod of the present invention has excellent welding process performance, stable arc, easy slag removal, small spatter, beautiful weld formation, good operability in all positions, reasonable control of alloy elements in the deposited metal, and good mechanical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a physical picture of a nickel-chromium-molybdenum alloy welding rod in Example 1 of the present invention. DETAILED DESCRIPTION

[0023] The specific embodiments of the present invention will be described clearly and completely below in conjunction with specific examples. If no specific conditions are specified in the examples, the conventional conditions or the conditions recommended by the manufacturer are followed. If the instruments, reagents or raw materials used are not specifically specified, they all represent conventional products that can be purchased commercially.

[0024] Firstly, the present invention provides a nickel-chromium-molybdenum alloy welding rod, wherein the welding rod comprises a welding core and a coating, wherein the mass ratio of the welding core to the coating is 65% of the welding core and 35% of the coating. The outer diameter of the welding rod coating is Φ4.0X6.95-7.05mm.

[0025] The coating used in the present invention comprises the following components in parts by weight: 15.0-25.0 parts of carbonate; 25.0-35.0 parts of titanium dioxide; 4-8 parts of fluoride; 2.0-5.0 parts of silicon oxide; 2.0-5.0 parts of electrolytic manganese; 8.0-14.0 parts of metallic chromium; 7.0-12.0 parts of metallic nickel; 0.5-1.5 parts of chromium nitride; 3 parts of metallic molybdenum; and 0.5-1.2 parts of CMC.

[0026] The welding core used in the present invention is ER430L, which includes the following components in weight: C: ≤0.030 parts; Mn: 1.50-2.20 parts; Si: ≤0.35 parts; S: ≤0.015 parts; P: ≤0.023 parts; Cr: 16.0-17.5 parts; Ni: ≤1.0; Mo: ≤0.50 parts; Cu: ≤0.50 parts; N: ≤0.050 parts; the balance is Fe.

[0027] The cladding metal of the welding rod of the present invention comprises the following components in weight percentage: C 0.03-0.05%, Mn 0.4-0.7%, Cr 15.5-15.8%, Ni 5.7-5.9%, Mo 0.8-0.95%, Si≤0.30%, S≤0.020%, P≤0.030%, and the balance is Fe and inevitable impurities.

[0028] The present invention also provides a method for preparing a nickel-chromium-molybdenum alloy welding rod, comprising the following steps:

[0029] (1) After the components of the coating raw materials are uniformly mixed according to the proportions, a binder is added and stirred to obtain a mixture;

[0030] Specifically, the raw materials for preparing the coating are mixed according to the component ratio and added to a blender, and stirred for 5 minutes to make the raw materials uniformly mixed. Then, a binder is added to the blender and stirred for 5 minutes to make the binder uniformly dispersed in the raw materials to obtain a mixture. The binder used in the present invention is potassium sodium water glass, the potassium sodium ratio is 3:1, and the weight ratio of the binder addition amount to the raw materials for the coating is 0.18 to 0.21:1.

[0031] (2) Add the mixture prepared in step (1) and the welding core into a pressure coating machine, uniformly prepare and shape the surface of the welding core, and then bake at low temperature and high temperature to obtain the welding rod.

[0032] Specifically, the mixture prepared in step (1) and the welding core are sequentially added to the pressure coating machine, and the pressure parameters are set to produce welding rods. In the present invention, the welding core is first cut, and the size can be adjusted according to actual production requirements. The pressure of the pressure coating machine is set to 140Mpa. After the pressure coating is completed, the product is first baked at 80-120°C and then baked at 360°C.

[0033] The present invention also provides a method for using a nickel-chromium-molybdenum alloy welding rod, comprising the following steps:

[0034] S1. Welding: First bake and heat the welding rod and the workpiece to be welded, and after heating, set the welding parameters for welding;

[0035] Specifically, the welding rod prepared as above and the workpiece to be welded are baked and heated, wherein the welding workpiece targeted by the present invention includes workpieces with complex structures such as aviation casting valves that require secondary heat treatment after welding. The welding rod baking temperature is 350°C, the baking time is 1h, and the baking temperature of the workpiece is 150°C. The welding machine is a ZX5-500 thyristor rectifier arc welding machine, the welding current is 150-160A, the welding voltage is 22V, the interpass temperature is less than or equal to 110°C, and the welding line energy is 11KJ / cm.

[0036] S2. Heat treatment: The welded workpiece is heat treated to obtain a complete welded part.

[0037] Specifically, the welded workpiece is heat treated according to the corresponding manufacturing requirements. The welding rod prepared in the present invention can meet any of the following heat treatment methods:

[0038] a. Keep at 580℃ for 4 hours, then air cool to room temperature; b. Keep at 590℃ for 8 hours, then cool to 300℃ with the furnace, and then air cool to room temperature; c. Keep at 1030℃ for 1 hour, then air cool to 590℃, keep warm for another 8 hours, then cool to 300℃ with the furnace, and then air cool to room temperature.

[0039] Example 1

[0040] The medicine coating in this embodiment includes the following components in parts by weight:

[0041] Carbonate: 22 parts; titanium dioxide: 31 parts; fluoride: 6.5 parts; silicon oxide: 4 parts; electrolytic manganese: 4 parts; metallic chromium: 13 parts; metallic nickel: 11 parts; chromium nitride: 1 part; metallic molybdenum: 2.5 parts; CMC: 1 part.

[0042] The welding core is ER430L, which includes the following weight components: C: ≤0.030 parts; Mn: 1.50-2.20 parts; Si: ≤0.35 parts; S: ≤0.015 parts; P: ≤0.023 parts; Cr: 16.0-17.5 parts; Ni: ≤1.0 parts; Mo: ≤0.50 parts; Cu: ≤0.50 parts; N: ≤0.050 parts; the balance is Fe. The mass ratio of welding core to coating is 65% for welding core and 35% for coating.

[0043] The cladding metal includes the following components in weight percentage: C 0.42%, Mn 0.51%, Cr 15.55%, Ni 5.7%, Mo 0.89%, Si 0.50%, S 0.008%, P 0.024%, and the balance is Fe and inevitable impurities.

[0044] This embodiment also provides a method for preparing a nickel-chromium-molybdenum alloy electrode, comprising the following steps: adding raw materials for preparing a coating to a blender according to the component ratio, and stirring for 5 minutes to evenly mix the raw materials. Then, a binder is added to the blender and stirred for 5 minutes to evenly disperse the binder in the raw materials to obtain a mixture. The binder used in the present invention is potassium-sodium water glass, the potassium-sodium ratio is 3:1, and the weight ratio of the binder addition to the coating raw material is 0.19:1.

[0045] The mixture prepared in step (1) and the welding core are sequentially added to the pressure coating machine, and the pressure parameters are set to produce welding rods. In the present invention, the welding core is first cut, and the size can be adjusted according to actual production requirements. The pressure of the pressure coating machine is set to 14Mpa. After the pressure coating is completed, the product is first baked at 100°C and then baked at 360°C.

[0046] This embodiment also provides a method for using a nickel-chromium-molybdenum alloy welding rod, comprising the following steps:

[0047] The welding rod prepared above and the workpiece to be welded are baked and heated, wherein the welding workpiece targeted by this embodiment is an aviation valve produced by Anhui Yingliu Co., Ltd. The welding rod baking temperature is 350°C, the baking time is 1h, and the baking temperature of the workpiece is 150°C. The welding machine is a ZX5-500 thyristor rectifier arc welding machine, the welding current is 155A, the welding voltage is 22V, the interpass temperature is less than or equal to 110°C, and the welding line energy is 11KJ / cm.

[0048] The welded workpieces are heat treated according to the corresponding manufacturing requirements. The heat treatment method in the present embodiment is: heat preservation at 580°C for 4 hours and then air cooling to room temperature.

[0049] Example 2

[0050] The difference between this embodiment and embodiment 1 is that the weight percentage of the cladding metal components used to prepare the welding rod and the weight percentage of the coating components used are different, specifically: carbonate: 18 parts; titanium dioxide: 31 parts; fluoride: 5 parts; silicon oxide: 4 parts; electrolytic manganese: 3 parts; metal chromium: 12 parts; metal nickel: 11.5 parts; chromium nitride: 1 part; metal molybdenum: 3 parts; CMC: 1 part. The mass ratio of the welding core to the coating is 65% for the welding core and 35% for the coating. The cladding metal includes the following weight percentages of the components: CO37%, Mn 0.471%, Cr 15.21%, Ni5.75%, Mo0.899%, Si0.421%, S 0.009%, P0.024%, and the balance is Fe and unavoidable impurities.

[0051] The welding rod prepared in this embodiment can meet the following heat treatment method: keep warm at 590° C. for 8 hours, then cool to 300° C. in the furnace and then cool to room temperature in the air.

[0052] Example 3

[0053] The difference between this embodiment and embodiment 1 is that the weight percentage of the cladding metal component used to prepare the welding rod and the weight percentage of the coating component used are different, specifically: carbonate: 22 parts; titanium dioxide: 28 parts; fluoride: 4 parts; silicon oxide: 3 parts; electrolytic manganese: 4 parts; metal chromium: 12 parts; metal nickel: 11.5 parts; chromium nitride: 1 part; metal molybdenum: 4.5 parts; CMC: 1 part. The mass ratio of the welding core to the coating is 65% for the welding core and 35% for the coating.

[0054] The cladding metal includes the following components in weight percentage: C 0.44%, Mn 0.622%, Cr 15.38%, Ni 5.75%, Mo 0.915%, Si 0.432%, S 0.008%, P 0.023%, and the balance is Fe and inevitable impurities.

[0055] The welding rod prepared in this embodiment can meet the following heat treatment method: keep warm at 1030°C for 1 hour, cool to 590°C with air, keep warm for 8 hours, cool to 300°C with the furnace, and then cool to room temperature with air.

[0056] Comparative Example 1

[0057] The difference between this comparative example and Example 1 is that the weight percentage of the cladding metal components used to prepare the welding rod and the weight percentage of the coating components used are different, specifically: carbonate: 21 parts; titanium dioxide: 31 parts; fluoride: 4 parts; silicon oxide: 3 parts; electrolytic manganese: 4 parts; metal chromium: 7 parts; metal nickel: 13 parts; chromium nitride: 1 part; metal molybdenum: 7 parts; CMC: 1 part. The mass ratio of the welding core to the coating is 2:10. The cladding metal includes the following weight percentages of the components: C 045%, Mn 0.677%, Cr 13.88%, Ni 6.52%, Mo 1.415%, Si 0.234%, S 0.011%, P 0.024%, and the balance is Fe and unavoidable impurities.

[0058] Comparative Example 2

[0059] The difference between this comparative example and Example 1 is that the weight percentage of the cladding metal component used to prepare the welding rod and the weight percentage of the coating component used are different, specifically: carbonate: 20 parts; titanium dioxide: 30 parts; fluoride: 6 parts; silicon oxide: 4 parts; electrolytic manganese: 4 parts; metal chromium: 17 parts; metal nickel: 11.5 parts; chromium nitride: 1 part; metal molybdenum: 7 parts; CMC: 1 part. The mass ratio of the welding core to the coating is 2:10.

[0060] The cladding metal includes the following components in weight percentage: C 0.40%, Mn 0.622%, Cr 16.57%, Ni 5.72%, Mo 1.28%, Si 0.502%, S 0.001%, P 0.020%, and the balance is Fe and inevitable impurities.

[0061] Performance Testing

[0062] The welding rod cladding metal performance test was carried out according to "GB / T 228.1-2010 Tensile test of metallic materials Part 1: Room temperature test method". The mechanical properties of the nickel-chromium-molybdenum alloy welding rod cladding metal prepared in each embodiment are shown in Table 1.

[0063] Table 1: Mechanical properties test results of welding rods prepared in Examples 1-3

[0064]

[0065] In summary, the welding rod of the present invention can adjust the welding performance and various mechanical properties of the welding rod by adjusting the content of nickel, chromium and molybdenum, so that it can comply with various post-welding heat treatment methods, thereby improving the adaptability and versatility of the welding rod.

[0066] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view. In addition, it should be understood that although this specification is described in accordance with the embodiments, it does not contain only one technical solution. This narrative of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in the embodiments can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A nickel-chromium-molybdenum alloy welding rod, comprising a welding core and a coating, characterized in that: The medicine coating comprises the following components in parts by weight: Carbonate: 15.0-25.0 parts; Titanium dioxide: 25.0-35.0 parts; Fluoride: 4-8 parts; Silicon oxide: 2.0-5.0 parts; Electrolytic manganese: 2.0-5.0 parts; Metal chromium: 8.0-14.0 parts; Metal nickel: 7.0-12.0 parts; Chromium nitride: 0.5-1.5 parts; Metal molybdenum: 2.5-5.0 parts; CMC: 0.5-1.2 parts.

2. A nickel-chromium-molybdenum alloy welding rod according to claim 1, characterized in that: The welding core comprises the following components in parts by weight: C: ≤0.030 parts; Mn: 1.50-2.20 parts; Si: ≤0.35 parts; S: ≤0.015 parts; P: ≤0.022 parts; Cr: 16.0-17.5 parts; Ni: ≤1.0; Mo: ≤0.50 parts; Cu: ≤0.50 parts; N: ≤0.050 parts; and the balance is Fe.

3. The nickel-chromium-molybdenum alloy welding rod according to claim 1, characterized in that: The mass ratio of the welding core to the coating is 65% for the welding core and 35% for the coating.

4. A nickel-chromium-molybdenum alloy welding rod according to claim 1, characterized in that: The cladding metal of the welding rod includes the following components in weight percentage: C 0.03-0.05%, Mn 0.4-0.7%, Cr 15.5-15.8%, Ni 5.7-5.9%, Mo 0.8-0.95%, Si≤0.30%, S≤0.020%, P≤0.030%, and the balance is Fe and inevitable impurities.

5. A method for preparing a nickel-chromium-molybdenum alloy welding rod, characterized in that: The following steps are involved: (1) After the components of the coating raw materials are uniformly mixed according to the proportions, a binder is added and stirred to obtain a mixture; (2) The mixture prepared in step (1) and the welding core are added to a pressure coating machine, and after being uniformly formed on the surface of the welding core, they are baked at low temperature and high temperature to obtain the welding rod.

6. The method for preparing a nickel-chromium-molybdenum alloy welding rod according to claim 5, characterized in that: The binder is potassium sodium water glass, and the ratio of potassium to sodium is 3:1; the weight ratio of the binder to the drug coating raw material is 0.18-0.21:1; the temperature of the low-temperature baking is 80-120°C, and the temperature of the high-temperature baking is 360°C.

7. A method for using a nickel-chromium-molybdenum alloy welding rod, characterized in that: The following steps are involved: S1. Welding: First bake and heat the welding rod and the workpiece to be welded, and then set the welding parameters for welding after heating is completed; S2. Heat treatment: The welded workpiece is heat treated to obtain a complete welded part.

8. A method for using a nickel-chromium-molybdenum alloy welding rod, characterized in that: In step S1, the electrode baking temperature is 350°C, the baking time is 1h, and the workpiece heating temperature is 150°C; the welding parameters include: welding current 150-160A, welding voltage 22V, interpass temperature less than or equal to 110°C, and welding line energy 11KJ / cm.

9. A method for using a nickel-chromium-molybdenum alloy electrode, characterized in that: The heat treatment in step S2 is any one of the following three methods: a. keeping at 580°C for 4 hours and then air cooling to room temperature; b. keeping at 590°C for 8 hours and then cooling to 300°C with the furnace and then air cooling to room temperature; c. keeping at 1030°C for 1 hour and then air cooling to 590°C and then keeping for another 8 hours, then cooling to 300°C with the furnace and then air cooling to room temperature.

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