阅读说明：本技术 一种电弧增材制造原位合金化方法 (In-situ alloying method for electric arc additive manufacturing ) 是由 魏文逸 于 2020-12-17 设计创作，主要内容包括：本发明公开了一种电弧增材制造原位合金化方法,包括以下步骤：A、对零件数模进行分层切片,并划分相应成形轨迹,将程序代码导入到相应的成形运动执行机构中；B、选取合金粉末置于真空干燥箱内烘干；C、对成形基板进行打磨,利用丙酮清洗基板表面；D、采用焊机产生的电弧热源对铝合金丝材进行熔化,在基板上形成一层沉积层；E、将合金化粉末均匀置于已成形层表面,随后利用同样装载于成形运动执行机构的轧辊对已预置粉末的成形层进行辊压,实现合金粉末的均匀地嵌入到已成形层表面；F、交替重复步骤D和步骤E,直至最后一层成形完成,使得预置的合金粉末在熔池对流的作用下均匀分布于整个成形件内部,实现电弧增材制造的原位合金化。(The invention discloses an in-situ alloying method for electric arc additive manufacturing, which comprises the following steps: A. carrying out layered slicing on the part digifax, dividing corresponding forming tracks, and importing program codes into corresponding forming motion execution mechanisms; B. selecting alloy powder and placing the alloy powder in a vacuum drying oven for drying; C. polishing the formed substrate, and cleaning the surface of the substrate by using acetone; D. melting the aluminum alloy wire by adopting an electric arc heat source generated by a welding machine to form a deposition layer on the substrate; E. uniformly placing the alloying powder on the surface of the formed layer, and then rolling the formed layer with the preset powder by using a roller which is also loaded on a forming motion actuating mechanism to uniformly embed the alloying powder into the surface of the formed layer; F. and E, alternately repeating the step D and the step E until the last layer of formed part is finished, so that the preset alloy powder is uniformly distributed in the whole formed part under the action of molten pool convection, and the in-situ alloying of the electric arc additive manufacturing is realized.)

1. An in-situ alloying method for electric arc additive manufacturing is characterized in that: the method comprises the following steps:

A. carrying out layered slicing on the part digifax, dividing corresponding forming tracks, and importing program codes into corresponding forming motion execution mechanisms;

B. selecting alloy powder and placing the alloy powder in a vacuum drying oven for drying;

C. polishing the formed substrate, and cleaning the surface of the substrate by using acetone;

D. melting the aluminum alloy wire by adopting an electric arc heat source generated by a welding machine to form a deposition layer on the substrate;

E. uniformly placing the alloying powder on the surface of the formed layer, and then rolling the formed layer with the preset powder by using a roller which is also loaded on a forming motion actuating mechanism to uniformly embed the alloying powder into the surface of the formed layer;

F. and E, alternately repeating the step D and the step E until the last layer of formed part is finished, so that the preset alloy powder is uniformly distributed in the whole formed part under the action of molten pool convection, and the in-situ alloying of the electric arc additive manufacturing is realized.

2. The electric arc additive manufacturing in-situ alloying method of claim 1, wherein: the welding process in-situ alloying adopts Metal Inert Gas (MIG) or Tungsten Inert Gas (TIG).

3. The electric arc additive manufacturing in-situ alloying method of claim 1, wherein: and B, placing the alloy powder with the granularity of 20-50 mu m selected in the step B in a vacuum drying oven for drying for 2 hours at the drying temperature of 120 ℃.

4. The electric arc additive manufacturing in-situ alloying method of claim 1, wherein: the forming motion actuating mechanism adopts a six-axis joint robot or a three-coordinate machine tool.

5. The electric arc additive manufacturing in-situ alloying method of claim 1, wherein: the welding machine adopts an arc fuse welding gun, the arc fuse welding gun and the roller are simultaneously fixed at the tail end of the movement executing mechanism through a fixture, and the welding gun for fuse forming and the roller for interlayer rolling are alternately replaced through the displacement mechanism.

6. The electric arc additive manufacturing in-situ alloying method of claim 1, wherein: in the forming process, a rectangular wave short edge swing forming mode is adopted.

7. The electric arc additive manufacturing in-situ alloying method of claim 1, wherein: the layer height of the forming piece is 1.5-2.5 mm.

Technical Field

The invention belongs to the technical field of additive manufacturing, and particularly relates to an in-situ alloying method for electric arc additive manufacturing.

Background

The electric arc additive manufacturing technology is a method for melting a welding wire by adopting an electric arc as a heat source and forming a three-dimensional solid part in a layer-by-layer cladding and accumulation mode under the control of a program. Compared with the additive manufacturing technology using high-energy beams such as laser beams and electron beams as heat sources, the electric arc additive manufacturing has the advantages of high forming efficiency, low equipment and raw material cost, high material utilization rate and the like, and can be used for forming and manufacturing large-size complex parts.

However, the wire components on the market are mainly proportioned for the welding process at present, the adaptability of the wire components to the arc additive process is poor, and the types of the wires are limited. At present, electric arc additive manufacturing mainly relies on adding fixed kinds of alloy wires. Although the existing twin-wire feeding technology can regulate and control the components of the formed part to a certain extent, the regulation and control range of the components is limited, and the application of the twin-wire feeding technology in the electric arc additive manufacturing technology is limited. The in-situ alloying method can realize the large-range regulation and control of the alloy components of the electric arc additive manufacturing formed part, more flexibly add different alloy components and further realize different performance requirements of the formed part.

At present, the prior patent technical documents for realizing the in-situ alloying method for the electric arc additive manufacturing mainly comprise: the invention patent document with the publication number of CN110004398A discloses an electric arc additive manufacturing in-situ alloying device and method for feeding powder by alternative fuses. In addition, the invention patent document with the publication number of CN110629218A discloses a high-entropy alloy fine grain in-situ additive manufacturing method, which combines a cold spraying process and an electric arc additive manufacturing process, adopts high-entropy alloy powder matched with a high-entropy alloy welding wire to realize in-situ alloying of high-entropy alloy electric arc additive manufacturing, and realizes the regulation and control of the structure and the components of the high-entropy alloy. However, the process needs to add an additional cold spraying device, and the cold spraying only impacts the surface of the deposition layer through high-speed gas jet, so that powder particles cannot be effectively embedded into the surface of the forming layer, and are easy to fall off, thereby influencing the accurate addition of alloying elements into the forming piece.

In addition, the device and the method adopting the synchronous feeding of the wire powder are effective measures for realizing the in-situ alloying of the electric arc additive, and the main processes comprise the modes of the coaxial feeding of the wire powder, the paraxial feeding of the powder and the like. The invention patent No. CN201910361072.1 discloses a method for manufacturing MIG electric arc additive of gradient titanium alloy with boron element in-situ strengthening, which realizes in-situ alloying strengthening of titanium alloy by boron element through a mode of synchronously feeding wire and powder. The patent with publication number CN108500266A discloses a 7000 series aluminum alloy additive manufacturing method and system, which also realizes the in-situ alloying of arc additive manufacturing by the synchronous powder feeding process. However, in the synchronous wire powder feeding process, the powder feeding needs airflow as a carrier, and the stability of the electric arc is affected while the alloy powder is fed, so that the stability of the integral forming process and the quality of a formed piece are affected.

Disclosure of Invention

Aiming at the problems, the invention makes up the defects of the prior art and provides an in-situ alloying method for electric arc additive manufacturing.

In order to achieve the purpose, the invention adopts the following technical scheme.

The invention discloses an in-situ alloying method for electric arc additive manufacturing, which is characterized by comprising the following steps of: the method comprises the following steps:

A. carrying out layered slicing on the part digifax, dividing corresponding forming tracks, and importing program codes into corresponding forming motion execution mechanisms;

B. selecting alloy powder and placing the alloy powder in a vacuum drying oven for drying;

C. polishing the formed substrate, and cleaning the surface of the substrate by using acetone;

D. melting the aluminum alloy wire by adopting an electric arc heat source generated by a welding machine to form a deposition layer on the substrate;

E. uniformly placing the alloying powder on the surface of the formed layer, and then rolling the formed layer with the preset powder by using a roller which is also loaded on a forming motion actuating mechanism to uniformly embed the alloying powder into the surface of the formed layer;

F. and E, alternately repeating the step D and the step E until the last layer of formed part is finished, so that the preset alloy powder is uniformly distributed in the whole formed part under the action of molten pool convection, and the in-situ alloying of the electric arc additive manufacturing is realized.

As a preferable aspect of the present invention, the welding process in the in-situ alloying uses Metal Inert Gas (MIG) welding or Tungsten Inert Gas (TIG) welding.

As another preferable scheme of the invention, the alloy powder with the granularity of 20-50 μm selected in the step B is dried in a vacuum drying oven for 2 hours at the drying temperature of 120 ℃.

In another preferred embodiment of the present invention, the forming motion actuator is a six-axis articulated robot or a three-coordinate machine tool.

In another preferred embodiment of the invention, the welding machine adopts an arc fuse welding gun, the arc fuse welding gun and the roller are simultaneously fixed at the tail end of the motion actuating mechanism through a fixture, and the welding gun for fuse forming and the roller for interlayer rolling are alternately replaced through a position changing mechanism.

As another preferable scheme of the invention, a rectangular wave short side swing forming mode is adopted in the forming process.

In another preferred embodiment of the present invention, the layer height of the shaped part is 1.5 to 2.5 mm.

The invention has the beneficial effects.

1. By the rolling method, in-situ presetting of alloy powder can be realized, and alloying of an arc additive manufacturing formed piece can be realized to the greatest extent.

2. The roller of the invention can uniformly embed the preset powder into the surface of the forming layer, and the applied rolling force can introduce the compressive stress into the forming layer, thereby improving the surface smoothness and realizing the refinement of the grain structure of the forming piece through deformation recrystallization.

3. The invention can realize the effective addition of the alloy powder into the formed piece, does not influence the stability of the forming process, and has the advantages of simple operation and low equipment cost.

Drawings

In order to make the technical problems, technical solutions and advantageous effects solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and the detailed description. It should be understood that the detailed description and specific examples, while indicating the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.

FIG. 1 is a schematic diagram of an arc additive deposition manufacturing process.

The labels in the figure are: 1. the welding device comprises a workbench, 2. a forming substrate, 3. a formed layer, 4. a molten pool, 5. a protective gas, 6. a welding wire and 7. an arc fuse welding gun.

FIG. 2 is a schematic diagram of in-situ alloying by powder pre-placement and rolling between layers.

The labels in the figure are: 8. rolling roller, 9, preset layer of alloy powder and 10, rolling layer.

Detailed Description

Example 1.

An electric arc additive manufacturing in-situ alloying method comprises the following steps:

A. carrying out layered slicing on the part digifax, dividing corresponding forming tracks, and importing program codes into corresponding forming motion execution mechanisms;

B. selecting alloy powder and placing the alloy powder in a vacuum drying oven for drying;

C. polishing the formed substrate, and cleaning the surface of the substrate by using acetone;

D. melting the aluminum alloy wire by adopting an electric arc heat source generated by a welding machine to form a deposition layer on the substrate;

E. uniformly placing the alloying powder on the surface of the formed layer, and then rolling the formed layer with the preset powder by using a roller which is also loaded on a forming motion actuating mechanism to uniformly embed the alloying powder into the surface of the formed layer;

F. and E, alternately repeating the step D and the step E until the last layer of formed part is finished, so that the preset alloy powder is uniformly distributed in the whole formed part under the action of molten pool convection, and the in-situ alloying of the electric arc additive manufacturing is realized.

The welding process in the in-situ alloying adopts Metal Inert Gas (MIG) or Tungsten Inert Gas (TIG); b, placing the alloy powder with the granularity of 20-50 mu m selected in the step B in a vacuum drying oven to be dried for 2 hours at the drying temperature of 120 ℃; the forming motion actuating mechanism adopts a six-axis joint robot or a three-coordinate machine tool; the welding machine adopts an arc fuse welding gun, the arc fuse welding gun and the roller are simultaneously fixed at the tail end of the motion actuating mechanism through a fixture, and the welding gun for fuse forming and the roller for interlayer rolling are alternately replaced through the displacement mechanism; a rectangular wave short edge swing forming mode is adopted in the forming process; the layer height of the forming piece is 1.5-2.5 mm.

Example 2.

A. Firstly, selecting an aluminum alloy substrate with the mark number of 5051 as a forming substrate, presetting through holes on the periphery of the aluminum alloy substrate, and clamping and fixing the aluminum alloy substrate on a workbench through bolts; polishing the surface of the substrate by using abrasive paper, and cleaning the surface of the substrate by using absolute ethyl alcohol and acetone; and preheating the substrate by adopting a preheating platform to ensure that the preheating temperature of the substrate reaches 200 ℃.

B. Selecting niobium powder with the diameter of 10-30 mu m, and drying in a vacuum drying oven at 120 ℃ for 120 min; uniformly mixing niobium powder and absolute ethyl alcohol, wherein the volume ratio of the niobium powder to the absolute ethyl alcohol is 1: 5, stirring the mixture by a glass rod to form a suspension.

C. Taking a formed aluminum alloy thin-wall structure as an example, carrying out layered slicing on part models and generating an electric arc additive manufacturing track, wherein a motion execution mechanism adopted is a six-axis joint robot; the arc fuse welding gun and the roller are fixed at the position of the robot arm through a special clamp, and the arc fuse welding gun is alternately switched between the rollers through a position changing mechanism; the welding wire is a wire material with the mark number of 5B 06; forming the aluminum alloy part in a CMT mode in an integrated welding mode, wherein a forming track adopts a rectangular wave short edge swinging mode, and forming parameters are set as follows: the wire feeding speed is 8m/min, the welding speed is 18mm/s, the swing distance is 2.5mm, the swing width is 10mm, the flow of argon protective gas is 20L/min, and the total length of the formed aluminum alloy thin-wall structure is 150 mm.

D. Firstly, forming a first priming layer on a forming substrate; after the forming is finished, mixed liquor of the mixed niobium powder and absolute ethyl alcohol is pre-arranged on the surface of the formed layer, so that the content of the niobium powder in the formed piece is 0.6%. It is to be noted that, in order to allow the anhydrous ethanol used for mixing the niobium powder to be rapidly volatilized, the interlayer temperature of the molding should be controlled to be 80 ℃ or higher.

E. The roller is switched to the position above the starting point of the forming layer by adopting a position changing mechanism, the roller is pressed down by a robot arm to generate roller pressure between the formed layers, rolling movement is carried out along the length direction of the thin-wall forming piece, and the alloy powder preset on the surface of the forming layer is uniformly embedded into the surface of the forming layer; and after rolling is finished, switching the welding gun to the position above the forming layer through the position changing mechanism, starting the deposition of the next layer, alternately performing the forming deposition-powder presetting-rolling process, and finally finishing the in-situ alloying of the whole forming piece.

The above examples are only preferred embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be able to cover the technical scope of the present invention, the technical solutions according to the present invention and the inventive concept thereof, with equivalent substitutions or changes.