CN114850499B

CN114850499B - Novel clay-based composite material supporting and printing device and method for arc 3D printing

Info

Publication number: CN114850499B
Application number: CN202210408278.7A
Authority: CN
Inventors: 刘浩; 钱宇亮; 熊旭辉; 朱嘉铭
Original assignee: Nanjing University of Aeronautics and Astronautics
Current assignee: Nanjing University of Aeronautics and Astronautics
Priority date: 2022-04-19
Filing date: 2022-04-19
Publication date: 2023-12-01
Anticipated expiration: 2042-04-19
Also published as: CN114850499A

Abstract

The invention provides an arc 3D printing-oriented clay-based novel composite material support, an arc 3D printing device and an arc 3D printing method. Compared with the existing common same material support printing mode, the electric arc welding 3D printing mode using clay as a support is extremely easy to remove support materials, the sintered clay only needs to be scraped off, and meanwhile, the surface stripping and even structural damage of a workpiece cannot be caused due to the fact that the clay is different from the workpiece material. The spacer layer between the workpiece and clay is manufactured in a laser sintering mode, and due to the characteristics of high laser sintering accuracy and the like, the dimensional accuracy of the manufactured workpiece can be ensured to be extremely high, and the step effect of the traditional Fused Deposition (FDM) printing mode is overcome. The equipment design with multiple processing ports can be used for optimizing and simplifying the process of processing the workpiece in a personalized and targeted manner at any time, and has extremely high freedom degree and wide optimizing potential. The processing flow can be optimized according to the material characteristics and the processing characteristics of the required workpiece, and the optimal solution can be found.

Description

Novel clay-based composite material supporting and printing device and method for arc 3D printing

Technical Field

The invention relates to an arc 3D printing-oriented clay-based novel composite material support, an arc 3D printing device and an arc 3D printing method, and belongs to the technical field of 3D printing.

Background

The three-dimensional printing technology based on fused deposition modeling (Fused Deposition Modeling, FDM) is one of the traditional printing technologies in the three-dimensional printing field, and is popular with wide equipment developers and users because the principle of layer-by-layer stacking and modeling by adopting the fused printing materials is simple and easy to realize, so that the three-dimensional printing technology can be suitable for printing various physical models and artworks.

When the FDM three-dimensional printer prints workpieces, the upper layer is formed by stacking the lower layer due to the accumulation of the forming process layer by layer, so that the printed workpieces are required to avoid suspended structures or suspended angles to be controlled in a smaller range.

At present, printing of workpieces containing suspended structures generally has two processing modes: 1. and the support is added, and the support is added below the workpiece suspension structure, so that the suspension structure is supported in the printing process, and the printing process is ensured to be normally carried out. The support material is typically the same material as the workpiece itself, and the support is tightly attached to the workpiece, resulting in the difficulty of removing or even structurally damaging the workpiece during the removal of the support after printing of the workpiece. 2. The whole FDM printing process is completed on an AC turntable in a multi-axis forming mode, and the turntable can turn back and forth and rotate around the vertical direction, so that the whole equipment is changed into a five-axis mechanism from a traditional three-axis mechanism. When the suspended structure of the workpiece is printed, the printed part is rotated to an angle capable of providing support for the suspended structure through rotation of the turntable, so that printing of the whole workpiece is ensured. However, the path planning algorithm of the forming mode is complex, five-axis linkage is often required, the control difficulty is high, the accuracy of calibrating the center of the turntable is very high, and an operator needs to calibrate the center of the turntable by virtue of abundant experience before printing. Because five-axis linkage is more complex than the common three-axis printing, the accumulated error of equipment installation has larger influence on the quality of the workpiece, has higher requirements on the manufacturing maintenance and the use of the equipment, has high cost and is not enough to be accepted by most audiences.

Disclosure of Invention

In order to solve the defects in the prior art, the invention aims to provide an arc 3D printing-oriented clay-based novel composite material support, an arc 3D printing device and an arc 3D printing method, which take the clay-based novel composite material as a main support, and can stably and economically print a workpiece on the premise of ensuring high precision of the workpiece.

In order to achieve the above object, the present invention adopts the following technical scheme:

a clay-based novel composite support for arc 3D printing comprises metal powder sintered on the outer contour path of a workpiece to form a spacing area, and clay paved outside the spacing area and fixed to be formed.

An electric arc 3D printing device taking clay as a support uses three-axis 3D printing equipment as a substrate, a motion structure is a single X-axis module, and two synchronous Y-axis modules and a Z-axis module jointly form a gantry type motion mechanism. The processing end adopts a tool changing mechanism to carry out the common combination of a plurality of processing ports, and can be provided with a supporting printing device, an arc welding processing device or a spacer processing device. The spacer processing equipment is used for finishing the laying of the outline shape of the workpiece to form a spacer; the support printing equipment is used for paving clay outside the interval area, filling the area outside the interval area and finishing the support processing of the upper-layer workpiece.

Further, the support printing apparatus includes a clay-filled screw extruder and a flame gun.

Further, the spacer processing apparatus includes a hopper containing metal powder and a laser sintering machine.

Further, the system also comprises a multi-port control board card; the multi-port control board card comprises a moving mechanism control port and a processing end control port; the process end control port includes a support printing portion, an arc welding process portion, and a spacer process portion.

Further, the support printing portion includes a clay paving port and a flame gun port.

Further, the spacer processing part comprises a hopper powder feeding port and a laser sintering port.

Further, for high volume repeat work piece processing requirements, pre-cut metal flakes may be used instead of laser sintering metal powder to form the spacer regions. An automatic mode can be selected, and a mechanical gripper port is added to grasp the metal sheet; or alternatively, a locating slot may be added to each foil for stacking of the foils during each layer of printing.

Further, the clay is a wet clay.

The printing method based on the arc 3D printing device comprises the following steps:

step 1, planning a path according to the outline of a workpiece, horizontally moving according to a designated track to finish powder paving of the outline shape of the workpiece, and replacing a port to perform laser sintering to fix powder to form a spacing region;

step 2, replacing a port of the clay spiral extruder, paving wet clay outside the interval area, filling the area outside the interval area, replacing a port of a flame spray gun to fix the clay, forming the clay, and finishing the support of an upper-layer workpiece;

step 3, replacing the port to carry out wire feeding and arc welding processing in the isolation area, and completing the processing of the workpiece layer only by filling in the area as the outer contour is finished;

step 4, finishing the printing of the layer, judging the printing process according to the counter, if the printing process is not finished, lifting the layer height, and repeating the steps; if the printing is finished, the processing port returns to the zero point, and the printing is finished;

and 5, destroying the sintered clay part and the interval area part, and taking out the workpiece.

The beneficial effects are that:

1. compared with the existing common same material support printing mode, the electric arc welding 3D printing mode using clay as a support is extremely easy to remove support materials, the sintered clay only needs to be scraped off, and meanwhile, the clay is different from the workpiece material, so that the surface of the workpiece is not stripped or even structurally damaged; compared with the water-soluble materials such as PVA which are also made of different materials, the cost is extremely high, and the water-soluble materials cannot be used for large-scale universal production. The wet clay has extremely low economic cost and wide potential for long-term development.

2. The spacer layer between the workpiece and clay is manufactured in a laser sintering mode, and due to the characteristics of high laser sintering accuracy and the like, the dimensional accuracy of the manufactured workpiece can be ensured to be extremely high, and the step effect of the traditional Fused Deposition (FDM) printing mode is overcome. Because the area of the spacing area is less, compared with a pure laser sintering mode, the manufacturing cost can be greatly reduced while the high precision of the workpiece is ensured.

3. The equipment design with multiple processing ports can be used for optimizing and simplifying the process of processing the workpiece in a personalized and targeted manner at any time, and has extremely high freedom degree and wide optimizing potential. The processing flow can be optimized according to the material characteristics and the processing characteristics of the required workpiece, and the optimal solution can be found.

4. In the machining process, the laser sintering metal powder is used for spacing the workpiece area and the clay area, so that the precision of the workpiece is ensured, and the condition for using clay as a support to reduce the cost can be provided. However, if the requirement of processing the workpieces is repeated in a large batch, the pre-cut metal sheet can be used for replacing the area of the laser sintering metal powder, and the processing cost can be further reduced on the premise of ensuring the processing quality of the workpieces.

Drawings

FIG. 1 is a schematic diagram of a control system;

FIG. 2 is an overall frame diagram of a processing tool;

FIG. 3 is a schematic view of a processing apparatus;

FIG. 4 is a schematic illustration of a process;

fig. 5 is a process flow diagram.

Detailed Description

The invention is further described below with reference to the accompanying drawings. The following examples are only for more clearly illustrating the technical aspects of the present invention, and are not intended to limit the scope of the present invention.

The invention discloses a novel three-dimensional printing mode. Including determining the overall architecture of the new print mode device and the print method.

In order to adapt to the printing mode, the universal three-axis three-dimensional printing equipment is required to be adjusted and modified. The overall architecture of the device is shown in the figure, and the existing universal numerical control board card cannot meet the personalized requirements due to the fact that the device is provided with a plurality of ports in the printing process. Therefore, a basic circuit board control system is needed to be used for secondary development to complete control realization of multiple ports. The control system has nine control ports, and is divided into a mobile control port part and a processing end control port part. The mobile control ports comprise an X-axis port, a Y-axis port and a Z-axis port. The processing end control port comprises a support printing part, an arc welding processing part and a spacer processing part, wherein the support printing part comprises a clay paving port 1, and the port 1 is a screw extruder filled with wet clay; a thermal power spray gun fixing port 2; the arc welding processing part comprises an arc welding gun port 3 and an arc welding wire feeding port 4; the processing part of the interval zone comprises a powder feeding port 5, wherein the port 5 is a hopper filled with metal powder, and a laser sintering port 6.

The overall architecture of the device is as follows: the upper computer is connected with the multi-port control board, the control board is connected with the driver, the driver is connected with the motors, and the motors are connected with the motion ports. The power supply, the radiator, the circuit protector and the control device are integrated into a control system.

First, it is determined that all devices are ready. And the upper computer is used for controlling the printer nozzle to return to the origin of coordinates, and the upper computer displays the origin of coordinates. The printing starts and the initial layer counter K is initialized to 1.

A print process diagram is shown in fig. 4. The main process flow diagram is shown in fig. 5.

The printing flow comprises the following steps:

1. and raising the processing tail end by a layer height, planning a path by CAM software according to the outline of the workpiece, horizontally moving the control port 5 according to a designated track, flowing out metal powder through the hopper port, and finishing powder paving of the outline shape of the workpiece. The port 6 is replaced, and the powder is sintered and fixed by a laser to form a space region. Excess powder was blown off with a fan.

2. And replacing the port 1, paving clay outside the interval area by using a wet clay screw extruder, filling the area outside the interval area, and determining the specific filling area according to the size of the workpiece. And replacing the port 2, fixing wet clay by using a flame spray gun, forming the wet clay, and finishing the supporting processing of the upper-layer workpiece.

3. And replacing the port 4, carrying out wire feeding and arc welding processing in the isolation area, and filling in the area to finish the processing of the workpiece layer because the outer contour is finished.

4. Judging whether the counter K reaches a threshold value, if not, adding one operation to K, returning to the step 1, and processing the upper layer again. If K reaches the threshold value, printing is completed, and the processing port returns to the zero point.

5. Breaking the sintered clay portion and the spacing region portion, and taking out the work piece.

The foregoing is merely a preferred embodiment of the present invention, and it should be noted that modifications and variations could be made by those skilled in the art without departing from the technical principles of the present invention, and such modifications and variations should also be regarded as being within the scope of the invention.

Claims

1. A printing method of an arc 3D printing device, characterized in that the arc 3D printing device includes a processing end, a moving mechanism and a multi-port control board; the processing end adopts a tool change mechanism, which can be installed to support printing equipment, Arc welding processing equipment or spacer processing equipment; the spacer processing equipment includes a hopper filled with metal powder and a laser sintering machine; the support printing equipment includes a screw extruder and a flame spray gun filled with clay; the multi-port The control board includes a moving mechanism control port and a processing end control port; the processing end control port includes a support printing part, an arc welding processing part and a spacer processing part; the support printing part includes a clay laying port and a flame spray gun port; The spacer processing part includes a hopper powder feeding port and a laser sintering port; the printing method includes the following steps:

Step 1. Plan the path according to the outer contour of the workpiece, move horizontally according to the specified trajectory to complete the powder laying of the outer contour shape of the workpiece, and replace the port for laser sintering to fix the powder to form a spacing area;

Step 2. Replace the clay screw extruder port, lay wet clay outside the interval area, fill the area outside the interval area, replace the flame spray gun port to fix the clay, shape it, and complete the support of the upper workpiece;

Step 3. Replace the port and perform wire feeding and arc welding processing in the isolation area. Since the outer contour has been completed, only filling in the area is required to complete the processing of the workpiece layer;

Step 4. Complete the printing of this layer, and judge the printing progress according to the counter. If it is not completed, raise the layer height and repeat the above steps; if it is completed, the processing port returns to zero point to complete printing;

Step 5. Destroy the sintered clay part and the spacer area part, and take out the workpiece.

2. The printing method of an arc 3D printing device according to claim 1, characterized in that the interval processing equipment includes a mechanical gripper, and the mechanical gripper is used to grip pre-cut metal sheets to form The spacer area is used to replace the laser sintering fixed powder to form a spacer area.

3. The printing method of an arc 3D printing device according to any one of claims 1-2, characterized in that the clay is wet clay.