A particulate reinforced maraging steel flux cored filler wire for twin wire arc additive manufacturing and method

Abstract

A kind of granular enhanced martensitic age steel cored filling wire for double-wire electric arc additive manufacturing and method, it relates to the field of additive manufacturing.Cored filling wire 1: manganese powder 0.5%-1%, cobalt powder 34%-36%, titanium powder 4%-5%, aluminum powder 1%-2%, molybdenum powder 47%-48%, the balance is iron powder;The outer skin is selected with low-carbon steel strip, and the carbon content is less than 0.03%;Cored filling wire 2: cobalt powder 18%-19%, ceramic particles 0.5%-2%, the balance is iron powder;The outer skin is made of iron-nickel alloy steel strip, and the mass ratio of Fe and Ni is 1:1;The filling rate is 20%-30%.The current control range is 160A-200A.The wire feeding speed is 150mm / min-160mm / min.Martensitic age steel component with good corrosion resistance and high strength can be obtained.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of electric arc additive manufacturing, and relates to component design of a dual-core filling wire for a particle-reinforced maraging steel, in particular to a process method for manufacturing a particle-reinforced maraging steel by using a dual-wire electric arc additive manufacturing method. BACKGROUND

[0002] A maraging steel is a special ultra-high-strength steel that takes Fe-Ni martensite with no carbon or ultra-low carbon (carbon content ≤ 0.03%) as a base, adds different amounts of Co, Mo, Ti, Al and other elements, and is strengthened by precipitating fine and dispersed intermetallic compounds in the lath martensite matrix through aging treatment. It has high strength and toughness, and the heat treatment process is relatively simple. It has been widely used in precision molds, aerospace rocket engine casings, automobile manufacturing and other fields.

[0003] Additive manufacturing is the most potential technology in the whole advanced manufacturing technology system. As an important branch of additive manufacturing, electric arc additive manufacturing technology uses an electric arc as a heat source to melt the filling wire, and directly manufactures solid parts through layer-by-layer accumulation. It has the advantages of high manufacturing efficiency, high flexibility and low cost, and has broad application prospects in maraging steel rapid forming, efficient repair and remanufacturing.

[0004] In existing electric arc additive manufacturing technology of maraging steel, the mechanical properties of the additive parts are generally low, which is difficult to meet the application requirements. Ceramic particles have the characteristics of small aspect ratio and difficulty in forming obvious orientation. By adding micro-nano reinforcing particles to the filling material, the heterogeneous nucleation effect is realized, which is an effective way to improve the material structure and enhance the mechanical properties. Chinese patent (publication number CN202010165374.4) proposes a composite particle reinforced metal powder core welding wire suitable for CMT electric arc additive manufacturing, which uses a method of reinforcing the metal powder core with nano-tungsten carbide and titanium carbide composite particles. Dispersed titanium carbide is used as a heterogeneous nucleation point for primary carbide to hinder the growth of primary carbide, refine the structure, and obtain better additive manufacturing effect. Chinese patent (publication number CN202111673864.6) proposes a method of adding titanium diboride particles to a nickel-based core wire, which modifies the precipitation-hardened nickel-based alloy Inconel 718 to improve the comprehensive performance of the TIG welding additive composite cladding layer.

[0005] According to the search of the prior art, it is found that there is currently a lack of particle reinforced martensitic age hardening steel filling wire special for electric arc additive manufacturing, and there is no related research and application report on electric arc additive manufacturing of particle reinforced martensitic age hardening steel. It is difficult to change the alloy composition or add particle reinforced phase by using solid filling wire, thereby limiting its application in related aspects, while the method of using cored filling wire is easy to adjust the alloy composition and ratio and add particle reinforced phase, which provides a new idea for improving the comprehensive performance of martensitic age hardening steel by electric arc additive manufacturing, and this is the idea of the present application. SUMMARY

[0006] In order to solve the above limitations and deficiencies, the present application designs a ceramic particle reinforced martensitic age hardening steel double cored filling wire, which overcomes the disadvantage that the composition design and element content of the single powder cored filling wire cannot be considered, and proposes a process method for preparing particle reinforced martensitic age hardening steel by double cored filling wire TIG electric arc additive manufacturing, especially using double wire feeding TIG electric arc additive manufacturing to prepare martensitic age hardening steel with specific composition and particle reinforced content, so as to obtain martensitic age hardening steel components with good wear resistance and high strength.

[0007] In order to achieve the above purpose, the specific scheme adopted by the present application is as follows:

[0008] A martensitic age hardening steel cored filling wire for double wire electric arc additive manufacturing, comprising a first cored filling wire and a second cored filling wire.

[0009] The first cored filling wire comprises an outer skin and a cored powder. The outer skin is made of low carbon steel strip; according to mass percentage, the cored powder comprises manganese powder 0.5%-1%, cobalt powder 34%-36%, titanium powder 4%-5%, aluminum powder 1%-2%, molybdenum powder 47%-48%, and the balance is iron powder.

[0010] As a further optimization of the above scheme, the outer skin width of the low carbon steel strip is 20mm, and the thickness is 0.7mm.

[0011] As a further optimization of the above scheme, the carbon content of the low carbon steel strip is less than 0.03%, so as to avoid introducing too much carbon element in the steel strip. Its composition includes carbon content 0.03%, manganese content 0.06%, and the balance is iron content.

[0012] As a further optimization of the above scheme, the filling rate of the cored powder core of the first cored filling wire is 20%-30%.

[0013] As a further optimization of the above scheme, the diameter of the first cored filling wire seamless cored filling wire is

[0014] 1.2mm-2.4mm.

[0015] The second drug core filling wire comprises an outer skin and a drug core powder.

[0016] As a further optimization of the above scheme, the outer skin of the iron-nickel alloy steel belt has a width of 20 mm and a thickness of 0.7 mm.

[0017] As a further optimization of the above scheme, the mass ratio of Fe to Ni in the iron-nickel alloy steel belt is 1:1.

[0018] As a further optimization of the above scheme, the ceramic particles can be any one of silicon carbide particles, titanium diboride particles, titanium carbide particles, and vanadium carbide particles.

[0019] As a further optimization of the above scheme, the particle size of the ceramic particles is 3-6 mu m.

[0020] As a further optimization of the above scheme, the filling rate of the second drug core filling wire is 20-30%.

[0021] As a further optimization of the above scheme, the diameter of the second drug core filling wire is 1.2-2.4 mm.

[0022] The design and selection of the element components of the drug core powder of the present application are based on the following:

[0023] One of the main roles of Ni is to make the matrix obtain lath martensite containing high-density dislocations. Ni3Ti, Ni3Mo and other strengthening phases can be formed in the martensitic aging steel, ensuring high strength and high hardness. If the content of Ni is less than 10%, the toughness will decrease.

[0024] Co element can improve the martensite transformation temperature point (Ms) and promote the full transformation of martensite. At the same time, it improves the tempering stability, but too high content will reduce the toughness.

[0025] Mo is a ferrite forming element that can improve the corrosion resistance, high temperature strength and tempering performance of steel. It can make the steel precipitate fine close-packed cubic M2X phase during aging process. This precipitated phase has very high stability and can slow down the process of being replaced by carbide, thereby increasing the tempering stability and increasing the secondary hardening effect.

[0026] Al and Ti can fix impurities in steel, reduce segregation, and prevent intergranular corrosion.

[0027] One method of designing the composition of maraging steel is to control the martensite start temperature (Ms point). When the martensite transformation temperature is too low, there is a large amount of residual austenite in the cooling process of maraging steel, thereby weakening the precipitation strengthening effect, and the yield strength of the martensite matrix will decrease significantly. The chemical composition of the parent phase austenite is the dominant factor affecting the phase transformation temperature of maraging steel. Most of the alloying elements will lower Ms, such as C, Ni, Mn, Cu, etc., V and Ti have little effect on Ms, and Al, Co, etc. are alloying elements that increase Ms. According to the dependence of the above alloying elements on the martensite transformation temperature point, refer to the following empirical formula, appropriately adjust the alloy composition to control the martensite transformation starting temperature between 200-350℃, and promote the full transformation of martensite.

[0028] Ms = 767.7-305.4w(C)-30.6w(Mn)-14.5w(Si)-8.9w(Cr)-16.6w(Ni)+2.42(Mo)

[0029] +53w(V)+8.58w(Co)+40.4w(Al)+7.4w(W)-11.3w(Cu)

[0030] +510.4w(Nb)

[0031] And in the selection of ceramic particles, the melting point of VC is 2730℃, the density is 5.3g / cm 3 , the expansion coefficient is 4.2×10 -6 / ℃, the elastic modulus is 430GPa, and the hardness is 2090HV; the melting point of TiC is 3065℃, the density is 4.95g / cm 3 , the expansion coefficient is 7.7×10 -6 / ℃, the elastic modulus is 448GPa, and the hardness is 3000HV; the melting point of TiB2 is 2980℃, the density is 4.52g / cm 3 , the expansion coefficient is 8.1×10 -6 / ℃, the elastic modulus is 510GPa, and the hardness is 2650HV; the melting point of SiC is 2700℃, the density is 3.12g / cm 3 , the expansion coefficient is 3.6×10 -6 / ℃, the elastic modulus is 380GPa, and the hardness is 2600HV. Compared with other commonly used ceramic particles, these types of ceramic particles are more suitable for use as particle reinforced phases of 18Ni maraging steel.

[0032] Another technical solution of the application is a method for preparing a drug-filled wire, which is implemented according to the following steps:

[0033] Step 1, dry each core powder ingredient, and weigh the required grams according to the desired alloy composition with an electronic balance;

[0034] Step 2, heat and hold the dried core powder ingredients in a vacuum tube furnace filled with an argon atmosphere for a period of time;

[0035] Step 3, fill the dried core powder in the vacuum tube furnace into the U-shaped groove of the steel strip;

[0036] Step 4, after closing, assist rolling by ultrasonic vibration generated by an ultrasonic device, apply ultrasonic vibration in a certain direction to the drawing die to intensify thermal motion, effectively improve the plastic deformation ability of the metal strip, reduce stress concentration and work hardening of the strip, inhibit crack generation during deformation, improve the forming quality of the strip, and produce the flux-cored wire;

[0037] In step 4, first produce 3.0 mm flux-cored wire, and then produce the final required 1.2 mm-2.4 mm flux-cored wire by reducing the aperture multiple times.

[0038] Further limited, the heating temperature in step 2 is 150℃-250℃, and the holding time is 0.5h-1.5h.

[0039] Further limited, the power of the ultrasonic device in step 4 is set to 500W-2000W, and the vibration frequency is set to 20kHz-40kHz.

[0040] Another technical solution of the present application is:

[0041] A method for manufacturing maraging steel by double-wire TIG arc additive manufacturing, which uses a double-wire arc manufacturing system consisting of an arc welding power supply, a welding torch, a three-axis motion control platform, a first wire feeder, and a second wire feeder; wherein the anode of the arc welding power supply is connected to the welding torch, and the filler wire is fed into the welding torch through the built-in wire feeding conduit of the wire feeder, wherein the wire feeding pipes of the first wire feeder and the second wire feeder are respectively located on both sides of the welding torch, and the included angle between the axis of the filler wire 1 sent out by the first wire feeder and the axis of the filler wire 2 sent out by the second wire feeder is 45°-60°; a clamp is provided on the motion platform for fixing the substrate during use to ensure the stability of the substrate during the additive process.

[0042] Preferably, the arc welding power supply is a constant current power supply.

[0043] Preferably, the filler wire 2 containing a particle reinforced phase is located below the filler wire 1 not containing a particle reinforced phase to suppress the overflow of ceramic particles on the surface of the molten pool and improve the melting rate of the particles.

[0044] In the setting of process parameters:

[0045] Further limitation, the welding current of the welding machine is 160-200A.

[0046] Further limitation, the wire feeding speed of the first wire feeder and the second wire feeder is 150mm / min-160mm / min.

[0047] Further limitation, the moving speed of the three-axis motion control platform is 120mm / min-170mm / min.

[0048] The method comprises the following steps:

[0049] Step 1, preheat the substrate, adjust the length of the tungsten electrode extending out of the welding gun;

[0050] Step 2, turn on the welding gun, set the welding current; turn on the first wire feeder and the second wire feeder, set the wire feeding speed; turn on 99% Ar shielding gas;

[0051] Step 3, set the walking control platform, preset it to start the arc, travel according to the preset path, stop wire feeding after traveling to the preset distance, extinguish the arc, lift the welding gun by 1cm distance, move the platform to make the welding gun return to the preset starting point, prepare for the next deposition;

[0052] Step 4, after a period of time, repeat the above step 3 until the size of the component reaches the requirement, and a martensitic age single-wall wall body is obtained.

[0053] Further limitation, the traveling direction of the platform is the rear, and the filler wire 1 and the filler wire 2 are both located behind the welding gun and fed into the arc.

[0054] Further limitation, the substrate in step 1 is a Q235 ordinary carbon structural steel plate with a size of 300*100*12mm, and the substrate is heated to 400 DEG C and then kept warm.

[0055] Further limitation, the length of the tungsten electrode extending out in step 1 is 6mm-8mm.

[0056] Further limitation, the shielding gas used in step 2 is 99.99% argon.

[0057] Compared with the prior art, the beneficial effects of the present application are:

[0058] The present application adopts double-rod wire arc additive manufacturing of 18Ni martensitic age steel, and the rod wire has the advantages of small welding spatter and high cladding speed, and good process performance. Through the double-rod wire, the alloy component ratio can be flexibly controlled, and ceramic reinforcing particles are added. The method of adding ceramic particles in the present application can improve the strength and wear resistance of the substrate to some extent, which is beneficial to increase the service life of the component. BRIEF DESCRIPTION OF DRAWINGS

[0059] Figure 1 Schematic diagram of the process for additive manufacturing of maraging steel by the method of the present application;

[0060] 1-welding power supply; 2-welding torch; 3-additive component; 4-substrate; 5-three-dimensional motion platform; 6-clamp;

[0061] 7-filler wire 1; 8-filler wire 2; 9-wire feeder 1; 10-wire feeder 2.

[0062] Figure 2 Schematic diagram of the double-wire ceramic particle deposition of the present application;

[0063] 11-filler wire 1; 12-filler wire 2; 13-ceramic particle; 14-melt droplet; 15-melt pool.

[0064] Figure 3 Schematic diagram of the distribution of ceramic particles in the matrix of the present application;

[0065] 16-matrix; 17-ceramic particle. DETAILED DESCRIPTION

[0066] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0067] The present application provides a double-cored filler wire for arc additive particle-reinforced maraging steel, comprising a cored powder and an outer sheath, wherein the outer sheath of the filler wire 1 is a low-carbon steel strip with a carbon content of 0.03%, a width of 20 mm, and a thickness of 0.7 mm; the cored powder used comprises, in terms of mass percentage, manganese powder 0.5%-1%, cobalt powder 34%-36%, titanium powder 4%-5%, aluminum powder 1%-2%, molybdenum powder 47%-48%, and the balance being iron powder, with the sum of the mass percentages of the above components being 100%; the outer sheath of the filler wire 2 is an iron-nickel alloy steel strip with a mass ratio of iron to nickel of 1:1, a width of 20 mm, and a thickness of 0.7 mm; the cored powder used comprises, in terms of mass percentage, cobalt powder 18%-19%, ceramic particles 0.5%-3.5%, and the balance being iron powder, with the sum of the mass percentages of the above components being 100%.

[0068] The manganese powder has a purity of ≥99.95% and a particle size of 100 mesh; the cobalt powder has a purity of ≥99.95% and a particle size of 100 mesh; the titanium powder has a purity of ≥99.95% and a particle size of 100 mesh; the molybdenum powder has a purity of ≥99.95% and a particle size of 100 mesh; the aluminum powder has a purity of ≥99.95% and a particle size of 100 mesh; the ceramic particles have a particle size of 3-6 μm.

[0069] The specific steps for additive manufacturing of a maraging steel single-wall wall body are as follows:

[0070] (1) Using a 300×100×12mm Q235 ordinary carbon structural steel plate as the substrate, the oxide layer on its surface is cleaned and polished, and the substrate is fixed on the motion platform by a clamp.

[0071] (2) Filler wire 1 and filler wire 2 are synchronously fed into the molten pool through the dual wire feeding system proposed in this invention;

[0072] (3) The feeding angles of filler wire 1 and filler wire 2 are adjusted by the wire feeding nozzle clamp to obtain a good dual-wire droplet transition mode;

[0073] (4) Turn on the welding gun, set the welding current, turn on the shielding gas, preheat the substrate surface to be deposited, further clean the surface oxide film, control the substrate temperature in the range of 170℃-200℃, and carry out the first layer additive manufacturing experiment.

[0074] (5) Connect the first wire feeder and the second wire feeder, set the wire feeding speed, and conduct a single-pass multi-layer additive manufacturing experiment until the component size meets the requirements, and obtain a martensitic aging steel single-wall wall.

[0075] Example 1

[0076] like Figure 1 As shown, this embodiment uses a welding torch integrating a first wire feeder and a second wire feeder to complete arc additive manufacturing. The design dimensions of the maraging steel single-wall component in this embodiment are 170mm × 10mm × 60mm. The filler wire 1 is a 1.6mm diameter filler wire with an outer sheath of low-carbon steel strip with a carbon content of 0.03%, and a core powder comprising 0.7% manganese powder, 35% cobalt powder, 4.5% titanium powder, 1.5% aluminum powder, 47% molybdenum powder, and the remainder being iron powder. The filler wire 2 is a 1.6mm diameter filler wire with an outer sheath of iron-nickel alloy steel strip with an iron-nickel mass ratio of 1:1, and a core powder comprising 18% cobalt powder, 0.5% silicon carbide particles, and the remainder being iron powder. The wire feed speed is 150mm / min, the platform movement speed is 140mm / min, and the welding current is 170A.

[0077] In this embodiment, the electric arc burns stably during the additive manufacturing process, the filler wire melts fully, and the additive manufacturing process can proceed continuously and stably. The resulting additive wall component has good forming, with no obvious pores or cracks, and a uniform internal structure, exhibiting the microstructural characteristics of metal additive manufacturing using electric arc wire. A room temperature uniaxial tensile test yielded a tensile strength of 1120 MPa and a microhardness of 332 HV. The wear resistance of the sample, tested using a ball-and-disc friction wear method, showed a wear rate of 3.01 × 10⁻⁶. -5 mm 3 / Nm.

[0078] Example 2

[0079] like Figure 1 As shown, this embodiment uses a welding torch integrating a first wire feeder and a second wire feeder to complete arc additive manufacturing. The design dimensions of the maraging steel single-wall component in this embodiment are 170mm × 10mm × 60mm. The filler wire 1 used is a 1.6mm diameter filler wire with an outer sheath of low-carbon steel strip with a carbon content of 0.03%, and a core powder comprising 0.7% manganese powder, 35% cobalt powder, 4.5% titanium powder, 1.5% aluminum powder, 47% molybdenum powder, and the remainder being iron powder. The filler wire 2 used is a 1.6mm diameter filler wire with an outer sheath of iron-nickel alloy steel strip with an iron-nickel mass ratio of 1:1, and a core powder comprising 18% cobalt powder, 1% silicon carbide particles, and the remainder being iron powder. The wire feed speed is 150mm / min, the platform movement speed is 140mm / min, and the welding current is 170A.

[0080] In this embodiment, the electric arc burns stably during the additive manufacturing process, the filler wire melts fully, and the additive manufacturing process can proceed continuously and stably. The resulting additive wall component has good forming, with no obvious pores or cracks, and a uniform internal structure, exhibiting the microstructural characteristics of metal additive manufacturing using electric arc wire. A room temperature uniaxial tensile test yielded a tensile strength of 1212 MPa and a microhardness of 341 HV. The wear resistance of the sample, tested using a ball-and-disc friction wear method, showed a wear rate of 2.63 × 10⁻⁶. -5 mm 3 / Nm.

[0081] Example 3

[0082] like Figure 1 As shown, this embodiment uses a welding torch integrating a first wire feeder and a second wire feeder to complete arc additive manufacturing. The design dimensions of the maraging steel single-wall component in this embodiment are 170mm × 10mm × 60mm. The filler wire 1 is a 1.6mm diameter filler wire with an outer sheath of low-carbon steel strip with a carbon content of 0.03%, and a core powder comprising 0.7% manganese powder, 35% cobalt powder, 4.5% titanium powder, 1.5% aluminum powder, 47% molybdenum powder, and the remainder being iron powder. The filler wire 2 is a 1.6mm diameter filler wire with an outer sheath of iron-nickel alloy steel strip with an iron-nickel mass ratio of 1:1, and a core powder comprising 18% cobalt powder, 1.5% silicon carbide particles, and the remainder being iron powder. The wire feed speed is 150mm / min, the platform movement speed is 140mm / min, and the welding current is 170A.

[0083] The electric arc is stable in the additive process, the filler wire is fully melted, the additive process can be continuously and stably carried out, the obtained additive wall member is well formed, no obvious pores and cracks are observed, the internal organization is uniformly distributed, and the microstructure characteristics of the electric arc wire metal additive manufacturing are presented. The tensile strength is 1293 MPa after room temperature uniaxial stretching, and the microhardness is 393 HV; the wear resistance of the sample is tested by the ball-on-disc friction and wear method, and the wear rate is 2.18x10 -5 mm 3 / Nm.

[0084] Example 4

[0085] As Figure 1 shown, the method of the present embodiment uses a welding gun integrated with a first wire feeder and a second wire feeder to complete the electric arc additive. The design size of the martensitic age hardened single-wall wall member of the present embodiment is 170mmx10mmx60mm, the filler wire 1 used is a low-carbon steel strip with a carbon content of 0.03%, the core powder used includes manganese powder 0.7%, cobalt powder 35%, titanium powder 4.5%, aluminum powder 1.5%, molybdenum powder 47%, and the balance is iron powder, and the diameter of the core filler wire is 1.6mm, the filler wire 2 used is an iron-nickel alloy steel strip with an iron-nickel mass ratio of 1:1, the core powder used includes cobalt powder 18%, silicon carbide particles 2%, and the balance is iron powder, and the diameter of the core filler wire is 1.6mm. The wire feeding speed is 150mm / min, the platform moving speed is 140mm / min, and the welding current is 170A.

[0086] The electric arc is stable in the additive process, the filler wire is fully melted, the additive process can be continuously and stably carried out, the obtained additive wall member is well formed, no obvious pores and cracks are observed, the internal organization is uniformly distributed, and the microstructure characteristics of the electric arc wire metal additive manufacturing are presented. The tensile strength is 1293 MPa after room temperature uniaxial stretching, and the microhardness is 393 HV; the wear resistance of the sample is tested by the ball-on-disc friction and wear method, and the wear rate is 2.18x10 -5 mm 3 / Nm.

[0087] Example 5

[0088] As Figure 1As shown, this embodiment uses a welding torch integrating a first wire feeder and a second wire feeder to complete arc additive manufacturing. The design dimensions of the maraging steel single-wall component in this embodiment are 170mm × 10mm × 60mm. The filler wire 1 is a 1.2mm diameter filler wire with an outer sheath of low-carbon steel strip with a carbon content of 0.03%, and a core powder comprising 0.7% manganese powder, 35% cobalt powder, 4.5% titanium powder, 1.5% aluminum powder, 47% molybdenum powder, and the remainder being iron powder. The filler wire 2 is a 1.2mm diameter filler wire with an outer sheath of iron-nickel alloy steel strip with an iron-nickel mass ratio of 1:1, and a core powder comprising 18% cobalt powder, 1.5% silicon carbide particles, and the remainder being iron powder. The wire feed speed is 150mm / min, the platform movement speed is 140mm / min, and the welding current is 170A.

[0089] In this embodiment, the electric arc burns stably during the additive manufacturing process, the filler wire melts fully, and the additive manufacturing process can proceed continuously and stably. The resulting additive wall component has good forming, with no obvious pores or cracks, and a uniform internal structure, exhibiting the microstructural characteristics of metal additive manufacturing using electric arc wire. A room temperature uniaxial tensile test yielded a tensile strength of 1168 MPa and a microhardness of 320 HV. The wear resistance of the sample, tested using a ball-and-disc friction wear method, showed a wear rate of 2.82 × 10⁻⁶. -5 mm 3 / Nm.

[0090] Example 6

[0091] like Figure 1 As shown, this embodiment uses a welding torch integrating a first wire feeder and a second wire feeder to complete arc additive manufacturing. The design dimensions of the maraging steel single-wall component in this embodiment are 170mm × 10mm × 60mm. The filler wire 1 is a 1.6mm diameter filler wire with an outer sheath of low-carbon steel strip with a carbon content of 0.03%, and a core powder comprising 0.7% manganese powder, 35% cobalt powder, 4.5% titanium powder, 1.5% aluminum powder, 47% molybdenum powder, and the remainder being iron powder. The filler wire 2 is a 1.6mm diameter filler wire with an outer sheath of iron-nickel alloy steel strip with an iron-nickel mass ratio of 1:1, and a core powder comprising 18% cobalt powder, 1.5% silicon carbide particles, and the remainder being iron powder. The wire feed speed is 150mm / min, the platform movement speed is 160mm / min, and the welding current is 170A.

[0092] In the additive process, the electric arc burns stably, the filler wire melts sufficiently, the additive process can be continuously and stably carried out, the obtained additive wall member is well formed, no obvious pores and cracks are observed, the internal structure is uniformly distributed, and the microstructure characteristics of the electric arc wire metal additive manufacturing are presented. The tensile strength is 1131 MPa after room temperature uniaxial tension, and the microhardness is 337 HV; the wear resistance of the sample is tested by the ball-on-disc friction and wear method, and the wear rate is 2.54x10 -5 mm 3 / Nm.

[0093] Example 7

[0094] As Figure 1 shown, the method of the present embodiment uses a welding gun integrated with a first wire feeder and a second wire feeder to complete the electric arc additive. The designed size of the martensitic age hardened single wall steel wall member of the present embodiment is 170mmx10mmx60mm, the filler wire 1 used is a low carbon steel strip with a carbon content of 0.03%, the core powder used includes manganese powder 0.7%, cobalt powder 35%, titanium powder 4.5%, aluminum powder 1.5%, molybdenum powder 47%, and the balance is iron powder, and the diameter of the core filler wire is 1.6mm, the filler wire 2 used is an iron-nickel alloy steel strip with an iron-nickel mass ratio of 1:1, the core powder used includes cobalt powder 18%, silicon carbide particles 1.5%, and the balance is iron powder, and the diameter of the core filler wire is 1.6mm. The wire feeding speed is 160mm / min, the platform moving speed is 160mm / min, and the welding current is 170A.

[0095] In the additive process, the electric arc burns stably, the filler wire melts sufficiently, the additive process can be continuously and stably carried out, the obtained additive wall member is well formed, no obvious pores and cracks are observed, the internal structure is uniformly distributed, and the microstructure characteristics of the electric arc wire metal additive manufacturing are presented. The tensile strength is 1131 MPa after room temperature uniaxial tension, and the microhardness is 337 HV; the wear resistance of the sample is tested by the ball-on-disc friction and wear method, and the wear rate is 2.54x10 -5 mm 3 / Nm.

[0096] Example 8

[0097] As Figure 1As shown, this embodiment uses a welding torch integrating a first wire feeder and a second wire feeder to complete arc additive manufacturing. The design dimensions of the maraging steel single-wall component in this embodiment are 170mm × 10mm × 60mm. The filler wire 1 used is a 1.6mm diameter filler wire with an outer sheath of low-carbon steel strip with a carbon content of 0.03%, and a core powder comprising 0.7% manganese powder, 35% cobalt powder, 4.5% titanium powder, 1.5% aluminum powder, 47% molybdenum powder, and the remainder being iron powder. The filler wire 2 used is a 1.6mm diameter filler wire with an outer sheath of iron-nickel alloy steel strip with an iron-nickel mass ratio of 1:1, and a core powder comprising 18% cobalt powder, 1.5% titanium carbide particles, and the remainder being iron powder. The wire feed speed is 150mm / min, the platform movement speed is 140mm / min, and the welding current is 170A.

[0098] In this embodiment, the electric arc burns stably during the additive manufacturing process, the filler wire melts fully, and the additive manufacturing process can proceed continuously and stably. The resulting additive wall component has good forming, with no obvious pores or cracks, and a uniform internal structure, exhibiting the microstructural characteristics of arc-wire metal additive manufacturing. A room-temperature uniaxial tensile test yielded a tensile strength of 1180 MPa and a microhardness of 410 HV. The wear resistance of the sample, tested using a ball-and-disc friction wear method, showed a wear rate of 2.42 × 10⁻⁶. -5 mm 3 / Nm.

[0099] Example 9

[0100] like Figure 1 As shown, this embodiment uses a welding torch integrating a first wire feeder and a second wire feeder to complete arc additive manufacturing. The design dimensions of the maraging steel single-wall component in this embodiment are 170mm × 10mm × 60mm. The filler wire 1 used is a 1.6mm diameter filler wire with an outer sheath of low-carbon steel strip with a carbon content of 0.03%, and a core powder comprising 0.7% manganese powder, 35% cobalt powder, 4.5% titanium powder, 1.5% aluminum powder, 47% molybdenum powder, and the remainder being iron powder. The filler wire 2 used is a 1.6mm diameter filler wire with an outer sheath of iron-nickel alloy steel strip with an iron-nickel mass ratio of 1:1, and a core powder comprising 18% cobalt powder, 1.5% vanadium carbide particles, and the remainder being iron powder. The wire feed speed is 150mm / min, the platform movement speed is 140mm / min, and the welding current is 170A.

[0101] In this embodiment, the electric arc burns stably during the additive manufacturing process, the filler wire melts fully, and the additive manufacturing process can proceed continuously and stably. The resulting additive wall component has good forming, with no obvious pores or cracks, and a uniform internal structure, exhibiting the microstructural characteristics of metal additive manufacturing using electric arc wire. A room temperature uniaxial tensile test yielded a tensile strength of 1237 MPa and a microhardness of 361 HV. The wear resistance of the sample, tested using a ball-and-disc friction wear method, showed a wear rate of 1.98 × 10⁻⁶. -5 mm 3 / Nm.

[0102] Example 10

[0103] like Figure 1 As shown, this embodiment uses a welding torch integrating a first wire feeder and a second wire feeder to complete arc additive manufacturing. The design dimensions of the maraging steel single-wall component in this embodiment are 170mm × 10mm × 60mm. The filler wire 1 used is a 1.6mm diameter filler wire with an outer sheath of low-carbon steel strip with a carbon content of 0.03%, and a core powder comprising 0.7% manganese powder, 35% cobalt powder, 4.5% titanium powder, 1.5% aluminum powder, 47% molybdenum powder, and the remainder being iron powder. The filler wire 2 used is a 1.6mm diameter filler wire with an outer sheath of iron-nickel alloy steel strip with an iron-nickel mass ratio of 1:1, and a core powder comprising 18% cobalt powder, 1.5% titanium diboride particles, and the remainder being iron powder. The wire feed speed is 150mm / min, the platform movement speed is 140mm / min, and the welding current is 170A.

[0104] In this embodiment, the electric arc burns stably during the additive manufacturing process, the filler wire melts fully, and the additive manufacturing process can proceed continuously and stably. The resulting additive wall component has good forming, with no obvious pores or cracks, and a uniform internal structure, exhibiting the microstructural characteristics of metal additive manufacturing using electric arc wire. A room temperature uniaxial tensile test yielded a tensile strength of 1204 MPa and a microhardness of 376 HV. The wear resistance of the sample, tested using a ball-and-disc friction wear method, showed a wear rate of 2.23 × 10⁻⁶. -5 mm 3 / Nm.

[0105]

Claims

1. A maraging steel cored filler wire for twin wire arc additive manufacturing, characterized in that, The first core filling wire and the second core filling wire are provided. The first core filling wire comprises an outer skin and a core powder; the outer skin is made of low carbon steel belt; the core powder comprises 0.5%-1% manganese powder, 34%-36% cobalt powder, 4%-5% titanium powder, 1%-2% aluminum powder, 47%-48% molybdenum powder, and the balance is iron powder; The filling rate of the core powder of the first core filling wire is 20%-30%. The second core filling wire comprises an outer skin and a core powder; the outer skin is made of iron-nickel alloy steel belt; the core powder comprises 18%-19% cobalt powder and 0.5%-3.5% ceramic particles, and the balance is iron powder; The filling rate of the second core filling wire is 20%-30%.

2. A maraging steel cored filler wire for twin wire arc additive manufacturing according to claim 1, characterized in that, The outer skin of the low carbon steel belt has a width of 20 mm and a thickness of 0.7 mm; the low carbon steel belt has a carbon content of less than 0.03% to avoid introducing too much carbon element into the steel belt; the composition of the low carbon steel belt includes 0.03% carbon content, 0.06% manganese content, and the balance is iron content.

3. A maraging steel cored filler wire for twin wire arc additive manufacturing according to claim 1, characterized in that, The diameter of the first core filling wire is 1.2 mm-2.4 mm; the diameter of the second core filling wire is 1.2 mm-2.4 mm.

4. A maraging steel cored filler wire for twin wire arc additive manufacturing according to claim 1, characterized in that, The outer skin of the iron-nickel alloy steel belt of the second core filling wire has a width of 20 mm and a thickness of 0.7 mm; the mass ratio of Fe to Ni in the iron-nickel alloy steel belt is 1:

1.

5. A maraging steel cored filler wire for twin wire arc additive manufacturing according to claim 1, characterized in that, The ceramic particles are any one of silicon carbide particles, titanium diboride particles, titanium carbide particles, and vanadium carbide particles; the particle size of the ceramic particles is 3 μm-6 μm.

6. A method of producing a maraging steel cored filler wire for twin wire electric arc additive manufacturing according to any one of claims 1-5, characterized in that, The method is implemented according to the following steps: Step 1: Dry each core powder ingredient, and weigh the required amount of alloy ingredients using an electronic balance; Step 2: Heat and maintain the dried core powder ingredients in a vacuum tube furnace filled with an argon atmosphere for a period of time; Step 3: Fill the dried core powder in the vacuum tube furnace into the U-shaped groove of the steel belt; Step 4: After closing, assist rolling by ultrasonic vibration generated by an ultrasonic device, apply ultrasonic vibration to the drawing die in a certain direction to intensify thermal motion, effectively improve the plastic deformation ability of the metal belt, reduce stress concentration and work hardening of the belt, inhibit crack generation during deformation, improve the forming quality of the belt, and produce the core welding wire; In step 4, first produce a 3.0 mm core welding wire, and then produce the final required 1.2 mm-2.4 mm core welding wire by reducing the hole diameter multiple times.

7. The method according to claim 6, characterized in that The heating temperature in step 2 is 150°C-250°C, and the holding time is 0.5 h-1.5 h; the power of the ultrasonic device in step 4 is set to 500 W-2000 W, and the vibration frequency is set to 20 kHz-40 kHz.

8. A method of performing double wire TIG arc additive manufacturing of maraging steel using the maraging steel cored filler wire of any one of claims 1-5, characterized in that, The application discloses a kind of double wire feeding arc manufacturing system, which is composed of arc welding power supply, welding torch, three-axis motion control platform, first wire feeder, second wire feeder;Wherein, arc welding power supply anode is connected with welding torch, filler wire is sent into welding torch by wire feeding machine through built-in wire feeding conduit, wherein the wire feeding pipe of first wire feeder and second wire feeder is located at the two sides of welding torch respectively, the included angle between the axis of first core filler wire sent by first wire feeder and the axis of second core filler wire sent by second wire feeder is 45°-60°;Clamp is arranged on motion platform, for fixing base plate during use to ensure the stability of base plate during additive process; The arc welding power supply is a constant current power supply; The second core filler wire containing particle reinforced phase is located below the first core filler wire without particle reinforced phase, which suppresses the overflow of ceramic particles on the surface of molten pool and improves the melting rate of particles; In the setting of process parameters: The welding current of welding machine is 160-200A, the wire feeding speed of first wire feeder and second wire feeder is 150mm / min-160mm / min, and the moving speed of three-axis motion control platform is 120mm / min-170mm / min.

9. The method of claim 8, wherein, The method comprises the following steps: Step 1, preheat the base plate, adjust the length of tungsten electrode extending out of welding torch; Step 2, turn on the welding torch, set the welding current;Turn on the first wire feeder and the second wire feeder, set the wire feeding speed;Turn on 99% Ar shielding gas; Step 3, set the walking control platform, preset it to start arc, travel according to the preset path, stop wire feeding after traveling to the preset distance, extinguish the arc, lift the welding torch by 1cm distance, move the platform to make the welding torch return to the preset starting point, prepare for the next deposition; Step 4, after a period of time, repeat step 3 above until the size of the component reaches the requirement, and a martensitic age single-wall wall body is obtained; The travel direction of the platform is backward, and the first core filler wire and the second core filler wire are located behind the welding torch and fed into the arc.

10. The method of claim 9, wherein, The base plate in step 1 is Q235 ordinary carbon structural steel plate with a size of 300×100×12mm, which is heated to 400℃ and then kept warm; The length of tungsten electrode extending out in step 1 is 6mm-8mm; The shielding gas used in step 2 is 99.99% argon.

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