Rare earth-containing sintering flux and preparation method and application thereof

Abstract

This invention relates to the field of welding technology, specifically to a rare-earth-containing sintered flux, its preparation method, and its application. The rare-earth-containing sintered flux is mainly composed of the following components by mass percentage: CaF2 43%–47%, CeO2 14%–18%, SiO2 16%–22%, FeO 8%–11%, K2O 7%–9%, ​​and ZrO2 2%–4%. This rare-earth-containing sintered flux possesses good low-temperature toughness, surface morphology, and slag removal performance. Furthermore, it produces welds with uniform composition and microstructure, high weld metal strength, strong stability during welding, high safety performance, and low environmental pollution.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of welding technology, in particular to a rare earth-containing sintered flux and a preparation method and application thereof. BACKGROUND

[0002] Compared with other welding methods, submerged arc welding has higher welding efficiency, excellent automation degree and relatively low cost, and is widely used in heavy industry fields, mainly including shipbuilding, oil exploitation equipment, etc. During welding, the flux uniformly covers the base material and the welding wire, protecting the weld from environmental pollution. Ship plate steel is mainly low-carbon low-alloy steel, and the mechanical properties of the welded joint can be improved by the optimization of the weld metal by the flux.

[0003] The sintered flux has the advantages of low processing temperature, simple operation method and uniform particle size of finished product. However, the sintered flux in the prior art is prone to defects in the weld after welding, and the mechanical properties of the weld are poor.

[0004] Therefore, the present application is proposed. SUMMARY

[0005] The first object of the present application is to provide a rare earth-containing sintered flux, which has good low-temperature toughness, surface morphology and deslagging performance, uniform weld composition and structure, and high weld metal strength.

[0006] The second object of the present application is to provide a preparation method of the rare earth-containing sintered flux.

[0007] The third object of the present application is to provide an application of the rare earth-containing sintered flux in welding.

[0008] In order to achieve the above objects of the present application, the following technical solutions are adopted:

[0009] The present application provides a rare earth-containing sintered flux, which mainly consists of the following components in terms of mass percentage: CaF2 43% to 47%, CeO2 14% to 18%, SiO2 16% to 22%, FeO 8% to 11%, K2O 7% to 9%, and ZrO2 2% to 4%.

[0010] The present application also provides a preparation method of the rare earth-containing sintered flux as described above, which comprises the following steps:

[0011] After uniformly mixing CaF2, CeO2, SiO2, FeO, K2O and ZrO2, add potassium water glass thereto, mix uniformly, granulate, and obtain granular material;

[0012] After sintering the granular material, the rare earth-containing sintered flux is obtained.

[0013] The application further provides application of the rare earth-containing sintered flux in welding.

[0014] Compared with the prior art, the application has the following beneficial effects:

[0015] (1) The CaF2 in the rare earth-containing sintered flux is added in an appropriate amount, so that the oxygen potential of the flux can be reasonably controlled, the O content can be better controlled, and the strength and toughness of the weld can be ensured.

[0016] (2) The rare earth-containing sintered flux can ensure the decomposition of CeO2 and the transition of Ce, and when the Ce content in the weld is sufficient, the structure of the weld can be greatly optimized.

[0017] (3) After the rare earth-containing sintered flux is used, the weld has good formability and excellent slag removal performance, and the loss of the weld composition is largely compensated, the content of acicular ferrite is high, and the mechanical properties of the weld are good. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the specific embodiments or the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or the prior art description. Obviously, the drawings described below are some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0019] Figure 1 The metallographic microscope image of the weld obtained after welding for Example 4 of the application is provided;

[0020] Figure 2 The SEM image of the weld obtained after welding for Example 4 of the application is provided;

[0021] Figure 3 Another SEM image of the weld obtained after welding for Example 4 of the application is provided;

[0022] Figure 4 The metallographic microscope image of the weld obtained after welding for Comparative Example 1 of the application is provided;

[0023] Figure 5 The SEM image of the weld obtained after welding for Comparative Example 1 of the application is provided;

[0024] Figure 6 Another SEM image of the weld obtained after welding for Comparative Example 1 of the application is provided. DETAILED DESCRIPTION

[0025] The technical solutions of the present application will be clearly and completely described below in combination with the drawings and specific embodiments, but those skilled in the art will understand that the following described embodiments are part of the embodiments of the present application, not all the embodiments, and are only used to illustrate the present application, and should not be regarded as limiting the scope of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application. If the specific conditions are not specified in the embodiments, the conventional conditions or the conditions recommended by the manufacturer are used. If the reagents or instruments used are not specified by the manufacturer, they are all conventional products that can be purchased on the market.

[0026] In a first aspect, the present application provides a rare earth-containing sintering flux, mainly composed of the following components in terms of mass percentage: CaF2 43% to 47%, CeO2 14% to 18%, SiO2 16% to 22%, FeO 8% to 11%, K2O 7% to 9%, and ZrO2 2% to 4%.

[0027] The content of CaF2 includes but is not limited to any one of the point values of 44%, 45%, 46%, or a range value between any two of them in terms of mass percentage.

[0028] The content of CeO2 includes but is not limited to any one of the point values of 15%, 16%, 17%, or a range value between any two of them in terms of mass percentage.

[0029] The content of SiO2 includes but is not limited to any one of the point values of 17%, 18%, 19%, 20%, 21%, or a range value between any two of them in terms of mass percentage.

[0030] The content of FeO includes but is not limited to any one of the point values of 9%, 10%, or a range value between any two of them in terms of mass percentage.

[0031] The content of K2O includes but is not limited to any one of the point values of 7.5%, 8%, 8.5%, or a range value between any two of them in terms of mass percentage.

[0032] The content of ZrO2 includes but is not limited to any one of the point values of 2.5%, 3%, 3.5%, or a range value between any two of them in terms of mass percentage.

[0033] The rare earth-containing sintering flux provided by the present application has a moderate content of CaF2, which ensures the flowability of the sintering flux during welding, blocks the outside atmosphere and impurities from polluting the molten pool during the welding process, and is combined with silicon dioxide to improve the deslagging property after welding and reduce the generation of weld defects. Moreover, the flux does not produce odor and splashing during welding, and meets the environmental emission standards.

[0034] The XRF test data show that the specific amount of CaF2 used in the application can control the oxygen content of the weld between 350-450ppm, and also has a good control effect on the content of other alloy elements, among which the content of Ce can reach more than 100ppm, and the burned Mn during welding is also well compensated.

[0035] Further, by adding a higher proportion of rare earth element Ce, the oxygen potential of the molten pool can be well controlled, the composition of the weld is greatly optimized, the structure of the weld is improved, the generation of defects in the weld is reduced, and the weld has high strength and high toughness.

[0036] Further, the metallic elements obtained by decomposing CeO2 and ZrO2 used in the application have variable valence, which can improve the activity of the flux, for example, under the action of arc plasma, the chemically active Ce generated by the decomposition of CeO2 at the slag-gold interface can combine with O in the molten pool to form CeO, Ce2O3, CeO2 and other oxides, and combine with other alloy elements to form a large number of effective inclusions, reduce the activation energy when needle-shaped ferrite is formed, reduce the energy barrier, optimize the weld structure, and further improve the mechanical properties of the welded joint.

[0037] Further, by using a specific amount of FeO, the alloy transition behavior of the weld can be improved, and the transition of various beneficial alloy elements from the flux to the weld can be promoted; the oxygen potential of the weld can also be improved to ensure that the decomposition degree of various oxides is within a reasonable range. Moreover, FeO combined with CaF2 can ensure sufficient fluidity, excellent formability of the weld, and uniform coverage of the flux, and prevent the flux from flowing to the surface of the weld and losing its protective effect.

[0038] In addition, the components of the rare earth-containing sintered flux provided by the application have a synergistic effect, for example, K2O combined with CaF2 can improve the arc stability of welding and reduce spatter; SiO2 combined with CaF2 can ensure the slag removal performance after welding, control the Si content of the weld, and improve the strength and hardness of the weld; CaF2 combined with ZrO2 can promote the formation of needle-shaped ferrite, refine the grains of the weld, and improve the mechanical properties of the weld while ensuring the stability during welding.

[0039] It is detected that the tensile fracture and impact fracture of the weld obtained after welding with the rare earth-containing sintered flux are typical ductile fractures, and a large number of dimples are included in the fracture morphology.

[0040] In conclusion, the rare earth-containing sintered flux provided by the application has good low-temperature toughness, surface morphology and slag removal performance, and the weld composition and structure are uniform, the weld metal strength is high, the stability during welding is strong, the safety performance is high, the environmental pollution is small.

[0041] Preferably, the rare earth-containing sintered flux mainly consists of the following components in terms of mass percentage: CaF243% to 47%, CeO215% to 17%, SiO218% to 21%, FeO 8% to 10%, K2O 7% to 9%, and ZrO22% to 4%.

[0042] Preferably, the particle size of the rare earth-containing sintered flux is 15 to 65 mesh, including but not limited to any one of 20 mesh, 30 mesh, 40 mesh, 50 mesh, 60 mesh or a range value between any two of them.

[0043] With the above range of particle size, the pollution of O to the weld caused by the air isolation due to the too large particle size can be avoided, and the problem of poor flowability of the slag liquid due to the too small particle size can also be avoided.

[0044] In a second aspect, the application provides a preparation method of the rare earth-containing sintered flux as described above, comprising the following steps:

[0045] After the CaF2, CeO2, SiO2, FeO, K2O and ZrO2 are uniformly mixed, potassium water glass is added thereto, and after being uniformly mixed, granulation is performed to obtain granular material.

[0046] The potassium water glass refers to a potassium silicate aqueous solution, and the chemical formula of the potassium silicate is K2O·nSiO2, wherein the modulus n = SiO2 / K2O (molar ratio).

[0047] It can be understood that the potassium water glass is sintered to form SiO2 and K2O, and therefore the amount of the potassium water glass needs to be considered when batching.

[0048] After the granular material is sintered, the rare earth-containing sintered flux is obtained.

[0049] The preparation method of the rare earth-containing sintered flux provided by the application has the advantages of simple operation, easy implementation, short process flow, mild conditions and batch production.

[0050] Preferably, the particle size of the granular material is 15 to 65 mesh, including but not limited to any one of 20 mesh, 30 mesh, 40 mesh, 50 mesh, 60 mesh or a range value between any two of them.

[0051] Preferably, the sintering temperature is 800 to 850℃, including but not limited to any one of 810℃, 820℃, 830℃, 840℃ or a range value between any two of them.

[0052] The holding time of the sintering is 90-120 min, including but not limited to 100 min, 110 min, or a range between any of the two.

[0053] In some specific embodiments of the present application, the number of granulation is at least once, preferably at least twice. Specifically, after the first granulation, the granules with a particle size of 15-65 mesh can be obtained. Then, the granules with a particle size greater than 15 mesh after the first granulation are crushed again, and the granules with a particle size less than 65 mesh are granulated again (i.e., the second granulation).

[0054] In some specific embodiments of the present application, the step of mixing CaF2, CeO2, SiO2, FeO, K2O and ZrO2 uniformly is as follows: after weighing CaF2, CeO2, SiO2, FeO, K2O and ZrO2, they are placed in a mixing device for mixing for 80-100 min. The mixing device includes but is not limited to a V-type three-dimensional mixer. Preferably, the frequency of the V-type three-dimensional mixer is 0.6-1 Hz.

[0055] In some specific embodiments of the present application, the water content (mass fraction) of the potassium water glass is 50%-55%, and the modulus of the potassium water glass is 2.5.

[0056] In some specific embodiments of the present application, the wet mixture is obtained after the potassium water glass is added and mixed uniformly. Then, the wet mixture is granulated.

[0057] In some specific embodiments of the present application, the ZSZL-1 granulator is used for granulation.

[0058] In some specific embodiments of the present application, before the sintering, the granules are dried. Preferably, the drying temperature is 500-650℃, and the drying time is 1-2 h.

[0059] In some specific embodiments of the present application, the sintering is carried out in an electromagnetic induction furnace, and the heating rate of the sintering is 6-8℃ / min.

[0060] In a third aspect, the present application provides the use of the rare earth-containing sintered flux as described above in welding.

[0061] The present application can improve the transition efficiency of Zr from the flux to the weld metal by reducing the overall oxygen potential of the flux, and can improve the optimization of the mechanical properties of the weld metal by the flux.

[0062] Preferably, the rare earth-containing sintered flux is used for welding ship plate steel.

[0063] The ship plate steel refers to a low-alloy high-strength steel used for ship manufacturing.

[0064] Preferably, the ship plate steel comprises at least one of A32 steel, AH32 steel, E32 steel, EH32 steel, D32 steel and DH32 steel.

[0065] Preferably, the method for welding comprises double-wire submerged arc welding.

[0066] Preferably, the welding line energy of the double-wire submerged arc welding is 30-45 kJ / cm, including but not limited to any one of 32 kJ / cm, 35 kJ / cm, 38 kJ / cm, 40 kJ / cm, 43 kJ / cm or a range value between any two of them.

[0067] Preferably, the welding speed of the double-wire submerged arc welding is 500-570 mm / min, including but not limited to any one of 510 mm / min, 520 mm / min, 530 mm / min, 540 mm / min, 550 mm / min, 560 mm / min or a range value between any two of them.

[0068] Preferably, the front wire of the double-wire submerged arc welding adopts direct current, and the welding current of the direct current is 570-640 A, including but not limited to any one of 580 A, 590 A, 600 A, 610 A, 620 A, 630 A or a range value between any two of them; the welding voltage of the direct current is 26-33 V, including but not limited to any one of 27 V, 28 V, 29 V, 30 V, 31 V, 32 V or a range value between any two of them.

[0069] Preferably, the rear wire of the double-wire submerged arc welding adopts alternating current, and the welding current of the alternating current is 430-480 A, including but not limited to any one of 440 A, 450 A, 460 A, 470 A or a range value between any two of them; the welding voltage of the alternating current is 26-33 V, including but not limited to any one of 27 V, 28 V, 29 V, 30 V, 31 V, 32 V or a range value between any two of them.

[0070] The above welding line energy, welding speed, welding current and welding voltage and other parameter ranges can further improve the mechanical properties of the welded joint.

[0071] In some specific embodiments of the present application, the welding machine used for welding is a POWER WAVE AC / DC 1000SD type welding machine produced by Lincoln Electric Co., Ltd.

[0072] Preferably, the welding wire used for the welding comprises at least one of J350DC welding wire, J421 welding wire, E4313 welding wire and E6013 welding wire.

[0073] The embodiments of the present application will be described in detail below with reference to the examples, but those skilled in the art will understand that the following examples are only for illustration of the present application and should not be regarded as limiting the scope of the present application. The specific conditions not noted in the examples are carried out according to the conventional conditions or the conditions suggested by the manufacturer. The reagents or instruments used are not noted for the manufacturer, which are all the conventional products available on the market.

[0074] The welding machine used in the following examples and comparative examples of the present application is POWER WAVE AC / DC 1000SD type welding machine produced by Lincoln Electric Co., Ltd.

[0075] Example 1

[0076] The rare earth-containing sintered flux provided in the present example is composed of the following components in terms of mass percentage: CaF2 46%, CeO2 15%, SiO2 20%, FeO 8%, K2O 7%, and ZrO2 4%.

[0077] The preparation method of the rare earth-containing sintered flux provided in the present example comprises the following steps:

[0078] (1) After weighing CaF2 46 parts, CeO2 15 parts, SiO2 10.8 parts, FeO 8 parts, K2O 1.2 parts and ZrO2 4 parts, add them into a three-dimensional mixing stirrer, mix at a frequency of 0.6 Hz for 100 min, and after mixing uniformly, obtain the mixed material. Add 30 parts of potassium water glass with a mass fraction of 50% and a modulus of 2.5 into the above mixed material, mix uniformly, and obtain the wet mixed material. Add the wet mixed material into a ZSZL-1 granulator for granulation, and obtain the granular material with a particle size of 15-65 mesh.

[0079] (2) Dry the granular material obtained in step (1) at 550℃ for 2 h, and then place it in an electromagnetic induction furnace for sintering. When sintering, heat at a rate of 8℃ / min, and after reaching the sintering temperature of 800℃, keep the temperature for 110 min, and then cool to room temperature with the furnace, to obtain the rare earth-containing sintered flux with a particle size of 15-65 mesh.

[0080] The embodiment also provides a method for welding ship plate steel by using the rare earth-containing sintered flux prepared in the embodiment, wherein the ship plate steel is A32 steel, and a welding wire used for welding is J350 DC welding wire. The method for welding is double-wire submerged arc welding. The welding line energy of the double-wire submerged arc welding is 36 kJ / cm, and the welding speed is 520 mm / min. The front wire of the double-wire submerged arc welding adopts direct current, the welding current of the direct current is 600 A, and the welding voltage of the direct current is 28 V; the rear wire of the double-wire submerged arc welding adopts alternating current, the welding current of the alternating current is 450 A, and the welding voltage of the alternating current is 28 V.

[0081] Embodiment 2

[0082] The rare earth-containing sintered flux provided in the embodiment is composed of the following components in percentage by mass: CaF2 45%, CeO2 16%, SiO2 21%, FeO 9%, K2O 7%, and ZrO2 2%.

[0083] The preparation method of the rare earth-containing sintered flux provided in the embodiment comprises the following steps:

[0084] (1) After 45 parts of CaF2, 16 parts of CeO2, 11.8 parts of SiO2, 9 parts of FeO, 1.2 parts of K2O, and 2 parts of ZrO2 are weighed, they are added into a three-dimensional mixing stirrer, mixed at a frequency of 1 Hz for 80 min, and then uniformly mixed to obtain a mixture. 30 parts of potassium water glass with a mass fraction of 50% and a modulus of 2.5 are added into the mixture, uniformly mixed, and then a wet mixture is obtained. The wet mixture is added into a ZSZL-1 granulator for granulation to obtain granular materials with a particle size of 15-65 mesh.

[0085] (2) The granular materials obtained in step (1) are dried at 580 ℃ for 2 h, and then are placed in an electromagnetic induction furnace for sintering. The sintering is performed at a rate of 6 ℃ / min, and after the sintering temperature of 840 ℃ is reached, the temperature is maintained for 120 min, and then the furnace is cooled to room temperature. Finally, the rare earth-containing sintered flux with a particle size of 15-65 mesh is obtained.

[0086] The embodiment also provides a method for welding ship plate steel by using the rare earth-containing sintered flux prepared in the embodiment, wherein the ship plate steel is AH32 steel, and a welding wire used for welding is E4313 welding wire. The method for welding is double-wire submerged arc welding. The welding line energy of the double-wire submerged arc welding is 30 kJ / cm, and the welding speed is 500 mm / min. The front wire of the double-wire submerged arc welding adopts direct current, the welding current of the direct current is 570 A, and the welding voltage of the direct current is 26 V; the rear wire of the double-wire submerged arc welding adopts alternating current, the welding current of the alternating current is 430 A, and the welding voltage of the alternating current is 26 V.

[0087] Embodiment 3

[0088] The rare earth-containing sintered flux provided by the embodiment is composed of the following components in percentage by mass: CaF2 43%, CeO2 17%, SiO2 19%, FeO 9%, K2O 9%, and ZrO2 3%.

[0089] The preparation method of the rare earth-containing sintered flux provided by the embodiment comprises the following steps:

[0090] (1) After 43 parts of CaF2, 17 parts of CeO2, 8.2 parts of SiO2, 9 parts of FeO, 2.3 parts of K2O, and 3 parts of ZrO2 are weighed, they are added into a three-dimensional mixing stirrer and mixed at a frequency of 0.9 Hz for 90 min. After uniform mixing, a mixture is obtained. 35 parts of potassium water glass with a mass fraction of 50% and a modulus of 2.5 are added into the mixture, and after uniform mixing, a wet mixture is obtained. The wet mixture is added into a ZSZL-1 granulator for granulation, and granules with a particle size of 15-65 mesh are obtained.

[0091] (2) The granules obtained in step (1) are dried at 590°C for 2 h, and then are placed in an electromagnetic induction furnace for sintering. During sintering, the temperature is raised at a rate of 7°C / min. After the sintering temperature of 810°C is reached, the temperature is maintained for 105 min, and then the furnace is cooled to room temperature. A rare earth-containing sintered flux with a particle size of 15-65 mesh is obtained.

[0092] The embodiment also provides a method for welding ship plate steel by using the rare earth-containing sintered flux prepared in the embodiment. The ship plate steel is E32 steel, and the welding wire used for welding is J421 welding wire. The welding method is double-wire submerged arc welding. The welding line energy of the double-wire submerged arc welding is 40 kJ / cm, and the welding speed is 550 mm / min. The front wire of the double-wire submerged arc welding adopts direct current, the welding current of the direct current is 620 A, and the welding voltage of the direct current is 32 V. The rear wire of the double-wire submerged arc welding adopts alternating current, the welding current of the alternating current is 460 A, and the welding voltage of the alternating current is 32 V.

[0093] Embodiment 4

[0094] The rare earth-containing sintered flux provided by the embodiment is composed of the following components in percentage by mass: CaF2 47%, CeO2 15%, SiO2 18%, FeO 9%, K2O 8%, and ZrO2 3%.

[0095] The preparation method of the rare earth-containing sintered flux provided by the embodiment comprises the following steps:

[0096] (1) Take CaF247 parts, CeO215 parts, SiO29.4 parts, FeO 9 parts, K2O 2.6 parts, and ZrO23 parts, and then add them into a three-dimensional mixing stirrer, mix at a frequency of 0.9 Hz for 95 min, and then uniformly mix to obtain a mixture. Add 28 parts of a 50% mass fraction and a modulus of 2.5 potassium water glass into the mixture, uniformly mix, and then obtain a wet mixture. Add the wet mixture into a ZSZL-1 granulator to granulate, and then obtain a granular material with a particle size of 15-65 mesh.

[0097] (2) Dry the granular material obtained in step (1) at 610°C for 2 h, and then place it in an electromagnetic induction furnace to sinter. When sintering, heat at a rate of 8°C / min, and then after reaching a sintering temperature of 850°C, keep the temperature for 120 min, and then cool to room temperature with the furnace, to obtain a rare earth-containing sintered flux with a particle size of 15-65 mesh.

[0098] The embodiment also provides a method for welding ship plate steel by using the rare earth-containing sintered flux prepared in the embodiment, wherein the ship plate steel is DH32 steel, and the welding wire used for welding is an E6013 welding wire. The welding method is double-wire submerged arc welding. The welding line energy of the double-wire submerged arc welding is 45 kJ / cm, and the welding speed is 570 mm / min. The front wire of the double-wire submerged arc welding adopts direct current, the welding current of the direct current is 640 A, and the welding voltage of the direct current is 33 V; the rear wire of the double-wire submerged arc welding adopts alternating current, the welding current of the alternating current is 480 A, and the welding voltage of the alternating current is 33 V.

[0099] Example 5

[0100] The embodiment provides a method for welding ship plate steel by using the rare earth-containing sintered flux prepared in the embodiment 1, wherein the ship plate steel is DH32 steel, and the welding wire used for welding is an E6013 welding wire. The welding method is double-wire submerged arc welding. The welding line energy of the double-wire submerged arc welding is 28 kJ / cm, and the welding speed is 480 mm / min. The front wire of the double-wire submerged arc welding adopts direct current, the welding current of the direct current is 550 A, and the welding voltage of the direct current is 24 V; the rear wire of the double-wire submerged arc welding adopts alternating current, the welding current of the alternating current is 400 A, and the welding voltage of the alternating current is 24 V.

[0101] Comparative Example 1

[0102] The rare earth-containing sintered flux provided in the comparative example is composed of the following components in percentage by mass: CaF247%, CeO210%, SiO222%, FeO 11%, K2O 7%, and ZrO23%.

[0103] The preparation method of the rare earth-containing sintered flux provided by the present comparative example is basically the same as that of Example 4, except that in the preparation of the mixture in step (1), the ingredients are weighed according to the following mass fractions: CaF247 parts, CeO210 parts, SiO213.4 parts, FeO 11 parts, K2O 1.6 parts, and ZrO23 parts (while the amount of potassium water glass remains unchanged).

[0104] The welding method and its parameters provided by the present comparative example are basically the same as those of Example 4, except that the rare earth-containing sintered flux prepared in Example 4 is replaced by the rare earth-containing sintered flux prepared in the present comparative example.

[0105] Comparative Example 2

[0106] The rare earth-containing sintered flux provided by the present comparative example is composed of the following components in mass percentage: CaF243%, CeO2 14%, SiO2 25%, FeO 8%, K2O 8%, and ZrO2 2%.

[0107] The preparation method of the rare earth-containing sintered flux provided by the present comparative example is basically the same as that of Example 3, except that in the preparation of the mixture in step (1), the ingredients are weighed according to the following mass fractions: CaF243 parts, CeO2 14 parts, SiO216.4 parts, FeO 8 parts, K2O 2.6 parts, and ZrO2 2 parts (while the amount of potassium water glass remains unchanged).

[0108] The welding method and its parameters provided by the present comparative example are basically the same as those of Example 3, except that the rare earth-containing sintered flux prepared in Example 3 is replaced by the rare earth-containing sintered flux prepared in the present comparative example.

[0109] Comparative Example 3

[0110] The rare earth-containing sintered flux provided by the present comparative example is composed of the following components in mass percentage: CaF240%, CeO2 22%, SiO2 18%, FeO 9%, K2O 8%, and ZrO2 3%.

[0111] The preparation method of the rare earth-containing sintered flux provided by the present comparative example is basically the same as that of Example 4, except that in the preparation of the mixture in step (1), the mass fraction of CaF2 is replaced by 40 parts, and the mass fraction of CeO2 is replaced by 22 parts.

[0112] The welding method and its parameters provided by the present comparative example are basically the same as those of Example 4, except that the rare earth-containing sintered flux prepared in Example 4 is replaced by the rare earth-containing sintered flux prepared in the present comparative example.

[0113] Experimental Example 1

[0114] The performance of the welds obtained after welding of each of the above examples and each of the comparative examples was detected, and the results are shown in Table 1.

[0115] Table 1: Performance detection results of the welds of each group

[0116]

[0117] The metallographic microscope image of the weld obtained after welding of Example 4 is shown in Figure 1 , the SEM image of the weld obtained after welding of Example 4 is shown in Figure 2 and Figure 3 .

[0118] The metallographic microscope image of the weld obtained after welding of Comparative Example 1 is shown in Figure 4 , the SEM image of the weld obtained after welding of Comparative Example 1 is shown in Figure 5 and Figure 6 .

[0119] Although the present application has been illustrated and described with reference to specific embodiments, it should be recognized that the above examples are merely illustrative of the present application and are not limiting thereof; it should be understood by those skilled in the art that modifications can be made to the technical solutions described in the above examples, or equivalent replacements can be made to some or all of the technical features thereof, without departing from the spirit and scope of the present application; these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the examples of the present application; therefore, this means that all such replacements and modifications within the scope of the present application are included in the appended claims.

Claims

1. A rare earth-containing sintering flux, characterized in that, It mainly consists of the following components by mass percentage Composition: CaF2 43%~47%, CeO2 14%~18%, SiO2 16%~22%, FeO 8%~11%, K2O 7%~9%, and ZrO2 2%~4%; The rare earth-containing sintered flux is used for welding ship plate steel. The welding method includes twin-wire submerged arc welding; The welding heat input of the dual-wire submerged arc welding is 30~45kJ / cm; The welding speed of the dual-wire submerged arc welding is 500~570mm / min; The front wire of the dual-wire submerged arc welding uses direct current, the welding current of the direct current is 570~640A, and the welding voltage of the direct current is 26~33V; The rear wire of the double-wire submerged arc welding uses alternating current, with a welding current of 430~480A and a welding voltage of 26~33V.

2. The rare earth-containing sintering flux according to claim 1, characterized in that, The rare earth-containing sintering flux mainly consists of the following components by mass percentage: Composition: CaF2 43%~47%, CeO2 15%~17%, SiO2 18%~21%, FeO 8%~10%, K2O 7%~9%, and ZrO2 2%~4%.

3. The rare earth-containing sintering flux according to claim 1, characterized in that, The particle size of the rare earth sintering flux is 15-65 mesh.

4. The rare earth-containing sintering flux according to claim 1, characterized in that, The ship plate steel includes at least one of A32 steel, AH32 steel, E32 steel, EH32 steel, D32 steel, and DH32 steel.

5. The rare earth-containing sintering flux according to claim 1, characterized in that, The welding wire used in the welding includes at least one of J350DC welding wire, J421 welding wire, E4313 welding wire and E6013 welding wire.

6. The method for preparing rare earth-containing sintering flux according to any one of claims 1 to 5, characterized in that, Includes the following steps: After CaF2, CeO2, SiO2, FeO, K2O and ZrO2 are mixed evenly, potassium silicate is added, and after mixing evenly, the mixture is granulated to obtain granular material. The granular material is sintered to obtain the rare earth-containing sintered flux.

7. The method for preparing rare earth-containing sintering flux according to claim 6, characterized in that, The particle size of the granules is 15-65 mesh.

8. The method for preparing rare earth-containing sintering flux according to claim 6, characterized in that, The sintering temperature is 800~850℃, and the sintering holding time is 90~120min.

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