CN-121972760-A - Ultra-short flow additive manufacturing method integrating invar alloy material synthesis and part preparation

Abstract

The invention provides an ultrashort flow additive manufacturing method integrating invar alloy material synthesis and part preparation, and belongs to the technical field of alloy manufacturing. The manufacturing method comprises the steps of verifying the consistency of a printing path, fixing a substrate, assembling a tungsten electrode in a welding gun, putting an iron wire and a nickel wire in a wire feeding mechanism, adjusting the wire feeding angle to enable a wire intersection point to be located under the tungsten electrode, configuring protective gas parameters, setting a welding power supply, the moving speed of the welding gun, the wire feeding speed and the heating parameters of a hot wire, starting a material adding manufacturing process after a preheating program is executed, adjusting the distance between the wire and a deposition layer by layer, and cooling after printing is finished to obtain the invar alloy part. The invention directly adopts iron wires and nickel wires as raw materials, and synthesizes the materials in a double-wire in-situ material adding mode, thereby realizing ultra-short flow material adding manufacturing. In addition, the double-wire in-situ material addition can also avoid macrosegregation defects in the casting process.

Inventors

• GUO YUELING
• YE SHUIJUN
• Di Xinglong
• LIU CHANGMENG

Assignees

• 北京理工大学

Dates

Publication Date

20260505

Application Date

20260310

Claims (10)

1. 1. An ultra-short flow additive manufacturing method integrating invar alloy material synthesis and part preparation is characterized by comprising the following steps: Step (1), building a three-dimensional model, generating a G code, importing the G code into a numerical control machine tool, and verifying the consistency of a printing path; Step (2), fixing a substrate, namely assembling a tungsten electrode in a welding gun, putting an iron wire and a nickel wire into a wire feeding mechanism, and adjusting a wire feeding angle to enable a wire intersection point to be located under the tungsten electrode; Step (3), configuring protective gas parameters, and setting welding power supply, welding gun moving speed, wire feeding speed and hot wire heating parameters; step (4), starting an additive manufacturing process after executing a preheating program; and (5) adjusting the distance between the wire and the deposition layer by layer, ensuring the position accuracy of the intersection point of the wire, and cooling after printing to obtain the invar alloy part.
2. 2. The ultra-short flow additive manufacturing method integrating invar alloy material synthesis and part preparation according to claim 1, wherein in the step (2), the diameter of an iron wire is 1.2mm, and the diameter of a nickel wire is 1.6mm.
3. 3. The ultra-short flow additive manufacturing method integrating invar alloy material synthesis and part preparation according to claim 1, wherein in the step (3), the shielding gas is argon, and the flow is 20-25L/min.
4. 4. The ultra-short flow additive manufacturing method integrating invar alloy material synthesis and part preparation according to claim 1, wherein in the step (3), a welding power source adopts direct current pulse, the peak current is 220-280A, the base current is 44-56A, the duty ratio is 25-35%, and the frequency is 0.6-1.0Hz.
5. 5. The ultra-short flow additive manufacturing method integrating invar alloy material synthesis and part preparation according to claim 1, wherein in the step (3), the moving speed of a welding gun is 80-120mm/min.
6. 6. The ultra-short flow additive manufacturing method integrating invar alloy material synthesis and part preparation according to claim 1, wherein in the step (3), wire feeding speeds of an iron wire and a nickel wire are 80-100cm/min and 70-90cm/min respectively.
7. 7. The ultra-short flow additive manufacturing method integrating invar alloy material synthesis and part preparation according to claim 1, wherein in the step (3), a direct current mode is adopted for hot wire heating, and iron wire hot wire current is 320-360A and nickel wire hot wire current is 280-320A.
8. 8. The method of claim 1, wherein in step (4), the preheating process is performed by turning on the machine tool and turning off the wire feeding state.
9. 9. The ultra-short flow additive manufacturing method integrating invar alloy material synthesis and part preparation according to claim 1, wherein in the step (5), the distance between the wire and the deposition layer is adjusted layer by layer, in particular to ensure that the intersection point of the iron wire and the nickel wire is always positioned on the deposition layer.
10. 10. The method of any one of claims 1-9, wherein in step (2), the substrate is a stainless steel substrate.

Description

Ultra-short flow additive manufacturing method integrating invar alloy material synthesis and part preparation Technical Field The invention relates to the technical field of alloy manufacturing, in particular to an ultra-short flow additive manufacturing method integrating invar alloy material synthesis and part preparation. Background Invar is a precise functional alloy with extremely low thermal expansion coefficient, and the linear expansion coefficient of the invar in an environment of-60 ℃ to 100 ℃ is only (1.0 to 2.0) multiplied by 10 -6/DEG C, which is far lower than that of common steel (about 11 multiplied by 10 -6/DEG C), so that the invar has irreplaceable core value in the field with strict requirements on dimensional stability. At present, invar alloy is widely applied to key components such as a precise connecting rod of an aerospace attitude control mechanism, a lens supporting frame of a photoetching machine, a resonant cavity of a 5G communication filter, a high-speed rail temperature compensator and the like, and the performance of the invar alloy directly determines the operation precision and the service life of high-end equipment. Currently, the preparation of invar alloy parts still uses prealloyed wires/powder as a core raw material, and has significant technical bottlenecks and cost barriers: The prealloyed wire has long preparation flow and high cost, and the traditional invar alloy wire needs more than ten working procedures such as pure iron-nickel raw material smelting, vacuum casting, hot rolling bar making, multi-pass cold drawing, surface pickling/electroplating, flaw detection and the like, and the production period is as long as 2-3 weeks. The casting link is easy to generate macrosegregation defect, so that uniformity of wire components is fluctuated, spectrum detection and flaw detection links are additionally added, energy consumption of multi-pass cold drawing is more than 35% of total cost of wire preparation, and market price of the final prealloyed wire is 3-5 times of that of pure iron and nickel wires. The additive manufacturing technology does not break through the bottleneck of raw material dependence, namely the existing main stream additive manufacturing technologies such as arc additive manufacturing, laser cladding and the like still need to take prealloyed wires or powder as raw materials, only realizes the automation of a part forming link, and does not simplify the preparation flow of invar alloy from the source. For example, when preparing invar alloy parts by arc additive, prealloyed wires are purchased firstly, and then arc melting deposition is carried out, so that the forming process of the wires is only carried forward, the problems of high cost and long period of wire preparation are not solved, and the powder bed melting technology can realize complex structure manufacturing, but the spheroidization preparation cost of invar alloy powder is higher, the deposition efficiency is low, and the production requirement of large structural parts is difficult to meet. The contradiction between the customization demand and the traditional mode is remarkable, and the demand for small-batch and multi-specification invar alloy parts is growing as high-end equipment is developed to be customized, light-weight and integrated. In the traditional mode, the minimum booking quantity of the customized wires is usually 500kg, the production period is prolonged by 1-2 weeks, the preparation cost of small batches of parts is improved by 2-3 times compared with that of standardized products, and the application expansion of invar alloy in the high-end customization field is seriously restricted. Therefore, the development of an ultra-short process technology for directly utilizing pure metal raw materials to synthesize invar alloy in situ and synchronously prepare parts breaks through the dependence bottleneck of prealloying raw materials, realizes dual promotion of cost reduction, efficiency improvement and performance stability, and becomes an urgent need in the field of high-end manufacture. Disclosure of Invention In view of the above, in order to solve the technical problems that the existing arc additive manufacturing technology still depends on prealloyed wires and the preparation process cannot be simplified from the source, the invention provides an ultra-short process additive manufacturing method integrating invar alloy material synthesis and part preparation, which directly adopts iron wires and nickel wires as raw materials and adopts a double-wire in-situ additive mode to synthesize invar alloy materials, thereby omitting the complicated invar alloy wire preparation process and realizing ultra-short process additive manufacturing. In addition, the double-wire in-situ material addition can also avoid macrosegregation defects in the casting process. In order to achieve the above purpose, the present invention provides the following technical solutions: An ultr