CN2761319Y

CN2761319Y - Fast shaping system for direct manufacturing metal parts

Info

Publication number: CN2761319Y
Application number: CN 200420057780
Authority: CN
Inventors: 黄树槐; 史玉升; 陈国清; 鲁中良
Original assignee: Huazhong University of Science and Technology
Current assignee: Huazhong University of Science and Technology
Priority date: 2004-12-15
Filing date: 2004-12-15
Publication date: 2006-03-01
Anticipated expiration: 2014-12-15

Abstract

The utility model discloses a rapid prototyping system for directly manufacturing metal parts. There are gas inlet and outlet ports on both sides of the gas protection chamber, and left and right powder falling devices for installing metal powder are arranged on both ends of the gas protection chamber. The powder falling device is in communication with each other; the scraper is located in the gas protection chamber, and is controlled by the motor to move in two directions along the horizontal direction; the laser scanning device is located between the left and right powder falling devices, and a laser window is set on the top of the gas protection chamber. There is a working chamber at the bottom of the protection chamber, in which there is a piston controlled by a motor to move up and down. The beam emitted by the laser scanning device is focused on the powder to be processed on the upper surface of the piston through the laser window. The utility model can directly produce metal parts with good mechanical properties such as high density, high strength and high precision in any complex shape, and has the characteristics of fast production speed and low production cost.

Description

A kind of rapid forming system of direct manufacturing metal parts

Technical field

The utility model belongs to quick manufacturing field, is specifically related to a kind of rapid forming system of direct manufacturing metal parts.

Background technology

Facts have proved that it is effective adopting RP technique to make the macromolecule part, but being used to make metal parts then exists many technical difficulties.Although some quick forming method can directly be made metal parts at present, but more be to obtain by indirect method.For example: selective laser sintering (Selective Laser Sintering, SLS) method---make metal parts by choosing refractory metal dusty material and low melting point powder material, the metal dust that is about to two kinds of different melting points mixes or certain binding agent of interpolation in metal dust, with less laser power (generally below 100W) melt portions low-melting-point metal powder or binding agent, unfused metal dust forms crude green body around the dusty material bonding of fusing, and then base substrate is carried out post processings formation metal parts such as high-temperature roasting, metallic cementation.Adopt existing method to make complicated metal parts fast, a series of problem such as have that density is low, mechanical performance is relatively poor, cost of manufacture is high, manufacturing process is complicated and fabrication cycle is long.In order to address these problems, selective laser fusing (Selective Laser Melting, the SLM) method that directly to make the high-compactness metal parts have been worked out at present.

The Fraunhofer institute of Germany has just worked out the SLM technology, present German MCP company and F﹠amp in 2002; S company is at production and selling SLM machine, and this equipment that they make all can directly be made metal parts, does not need subsequent treatment such as metallic cementation, and to obtain compactness be 100% workpiece.But what take in the equipment that they make is the mirror-vibrating laser scanning system, per hour can only produce 5cm ²Metal parts, production efficiency is lower; And the machine volume that they make is also bigger, and price is higher.

At present, the domestic report that does not also have the SLM rapid forming system.

Summary of the invention

The purpose of this utility model is to overcome above-mentioned weak point, and a kind of rapid forming system of direct manufacturing metal parts is provided.Adopt the utility model can directly produce metal parts any complicated shape, that have good mechanical properties such as high-compactness, high strength and high accuracy.In addition, adopt rapid forming system of the present utility model, can accelerate the manufacturing speed of metal parts, reduce cost of manufacture.

The rapid forming system of a kind of direct manufacturing metal parts that the utility model provides, comprise processing space and laser scanning device, it is characterized in that: the both sides in gas shield chamber are provided with inlet, outlet, it is provided with the left and right powder discharging device that is used for the splendid attire metal dust above two ends, powder discharging device is by its powder delivery of Electric Machine Control, and its meal outlet communicates with left and right powder discharging device; Scraper plate is positioned at the gas shield chamber, makes bidirectional-movement by the Electric Machine Control along continuous straight runs; Laser scanning device is between the left and right powder that falls is put; top in the gas shield chamber is provided with laser window; bottom in the gas shield chamber is provided with working chamber; be provided with the piston by its upper and lower motion of Electric Machine Control in the working chamber, the light beam that laser scanning device sends focuses on the metal powder to be processed of piston upper surface by laser window.

The utility model can directly produce the metal parts of good mechanical properties such as the high density, high strength, high accuracy of any complicated shape.In addition, adopt rapid forming system of the present utility model, can accelerate the manufacturing speed of metal parts, reduce cost of manufacture, economize on the use of funds.Native system is fit to directly make the high desnity metal part.

Description of drawings

Fig. 1 is the structural representation of the utility model SLM rapid forming system.

Fig. 2 is the structural representation of a kind of specific embodiment of powder discharging device among Fig. 1.

Fig. 3 is the structural representation of a kind of specific embodiment of laser scanning device among Fig. 1.

Fig. 4 is the control flow chart of SLM rapid forming system.

The specific embodiment

Below in conjunction with accompanying drawing and example the utility model is described in further detail.

As shown in Figure 1, in the utility model SLM rapid forming system, processing space 9 is made up of left and right

powder discharging device

10,11, laser window 13, scraper plate 15, piston 18, gas shield chamber 19, working chamber 20 and laser scanning device 21.Metal dust is equipped with in left and right

powder discharging device

10 and 11 inside, and its meal outlet communicates with gas shield chamber 19.As shown in Figure 2, be provided with the impeller 22 of band blade 23 in the left and right

powder discharging device

10 or 11, by the rotation of step motor control impeller, when two blades forwarded the exit position to, powder fell into gas shield chamber 19 automatically.Scraper plate 15 is positioned at 19 the insides, gas shield chamber, spreads powder by common electric machine control scraper plate 15 along continuous straight runs of Frequency Converter Control as bidirectional-movement.From left powder discharging device 10 to right powder discharging device 11 or right powder discharging device 11 once spread powder one deck to left powder discharging device 10 every motions; Laser scanning device 21 has a laser window 13 at the top in gas shield chamber 19 between left and right powder discharging device 10 and 11.Be provided with working chamber 20 in the bottom in gas shield chamber 19, be provided with piston 18 in its working chamber 20, piston 18 is vertically moved up and down by independent step motor control.The laser beam that laser scanning device 21 sends acts on the powder to be processed on piston 18 upper surfaces by laser window 13, and protective gas enters from air inlet 12 in the course of work, and 14 discharge from the gas outlet.Whenever process one deck, the distance of piston 18 declines one layer thickness, among the figure, the part workpiece that 16 expressions have been processed; The unnecessary metal dust of 17 expressions.

As shown in Figure 3, above-mentioned laser scanning device 21 is made of X-axis guide rail 1, Y-axis guide rail 2, polariscope 4 and 7, slide block 5, focus lamp 6.X-axis guide rail 1 and Y-axis guide rail 2 are made of screw mandrel, but Y-axis guide rail 2 along continuous straight runs under the control of servomotor is made bidirectional-movement, and X-axis guide rail 1 can be made bidirectional-movement along vertical Y axis rail 2 on horizontal plane under another servomotor control.Slide block 5 can be made bidirectional-movement by screw mandrel on Y-axis guide rail 2, focus lamp 6 and following polariscope 4 are fixed on the slide block 5, and last polariscope 7 is fixed on the upper end of Y-axis guide rail 2.The light beam 8 that laser instrument sends after focus lamp 6 focusing, focuses on the metal dust to be processed that is positioned at piston 18 upper surfaces by laser window 13 after changing traffic directions through last polariscope 7 and following polariscope 4.

The control flow chart of above-mentioned rapid forming system as shown in Figure 4.At first metal dust is preheating to uniform temperature by preheating device; Secondly by the fall metal dust of powder mechanism layer overlay predetermined thickness on processing platform of computer control; Design the solid modelling of metal parts at last with 3D sculpting softwares such as Pro/Engineer, Unigraphic, save as stl file after handling through section software then, the data message of stl file is transported in the SLM rapid forming system machine, under the laser scanning system of drawing ceremony X-Y axle scan mode, by of the track while scan operation of computer control laser according to design, the deposite metal powder is made layer by layer.Because when the system of the ceremony X-Y axle scan mode of taking to draw, laser is stabilized in a concrete numerical value through focusing on the back apart from processing platform, so spot size can not change, laser energy density is stable, guarantees machining accuracy easily; In addition, the hot spot after focusing in the 2-D vibration mirror formula laser scanning system becomes increasing to distal movement more, causes laser energy density to reduce gradually, if do not take indemnifying measure, possiblely will cause slowing down of the lower and process velocity of metal parts precision.Therefore, in order to improve process velocity and to obtain higher metal parts precision, in this rapid forming system, we have taked the laser scanning system of drawing ceremony X-Y axle scan mode.Simultaneously, the power spreading device of fall on we have taked powder mechanism and scraper plate combination, processing space is positioned at wherein, and this makes processing space compact more, has reduced the consumption of protective gas simultaneously, has saved cost.

Claims

1. A rapid prototyping system for directly manufacturing metal parts, including a processing space and a laser scanning device, characterized in that: the gas protection cavity (19) is provided with inlet and outlet ports (12, 14) on both sides, and the two ends are above There are left and right powder falling devices (10 and 11) for installing metal powder, and the powder falling device is controlled by a motor to discharge powder, and its powder outlet communicates with the left and right powder falling devices (10 and 11); the scraper ( 15) Located in the gas protection chamber (19), controlled by the motor to move in two directions along the horizontal direction; the laser scanning device (21) is located between the left and right powder falling devices (10 and 11), in the gas protection chamber (19) The top is provided with a laser window (13), and the bottom of the gas protection chamber (19) is provided with a working chamber (20). The working chamber (20) is provided with a piston (18) whose vertical movement is controlled by a motor. The laser scanning device The beam emitted by (21) is focused on the powder to be processed on the upper surface of the piston (18) through the laser window (13).

2. The system according to claim 1, characterized in that: the structure of the laser scanning device (21) is: the X-axis guide rail (1) and the Y-axis guide rail (2) are composed of screw rods, and the former is controlled by a servo motor The bottom can move in the horizontal direction, and the latter is controlled by another servo motor to move in the vertical direction on the horizontal plane. The slider (5) is located on the Y-axis guide rail (2) and slides along the Y-axis guide rail; the focusing mirror (6) and the lower polarizer (4) are fixed on the slider (5), the upper polarizer (7) is fixed on the upper end of the Y-axis guide rail (2), and the light beam (8) emitted by the laser passes through the upper polarizer (7) and After the lower polarizer (4) changes the running direction, it is focused by the focusing lens (6), and then irradiated on the metal powder to be processed on the upper surface of the piston (18) through the working window (13).

3. The system according to claim 1 or 2, characterized in that: the left and right powder falling devices (10 and 11) are impellers (22) with blades (23), and the rotation of the impellers is controlled by a motor, Make the powder fall into the gas protection chamber (19).