TWM501354U - Electromagnetic wave-assisted three dimensional printing device - Google Patents

Abstract

A three dimensional printing device including an electromagnetic wave generator, a preheating carrier and optical scanning unit is provided. The electromagnetic wave generator is adapted to generate an electromagnetic wave and define an electromagnetic wave preheating area, and the preheating carrier is disposed in the electromagnetic wave preheating area. The preheating carrier is adapted to carry powder, and the preheating carrier absorbs the electromagnetic wave and heats the powder to a first temperature. The optical scanning unit is adapted to emit a light to the powder and heats parts of the powder to a second temperature, and the first temperature is lower then the second temperature, and the second temperature is the sintering temperature or the melting point of the powder.

Description

Three-dimensional printing device using electromagnetic waves

The present invention relates to a processing apparatus, and more particularly to a three-dimensional printing apparatus.

With the development of technology, 3D printing technology and Additive Manufacturing (AM) technology have become one of the most important development technologies. These technologies are one of the rapid prototyping technologies. They can directly produce the desired finished product directly by the user-designed digital model file, and the finished product is almost a three-dimensional entity of any shape. The existing three-dimensional printing has various molding mechanisms according to various models and materials, and all materials such as liquid resin, slurry, metal (such as metal powder) or non-metal (such as ceramic powder) can pass through. Accumulate the layers by layer to construct a 3D solid of the desired shape. In the past, in the field of mold manufacturing, industrial design, etc., 3D printing technology is often used to make models, and now it is gradually used in jewelry, footwear, industrial design, construction, engineering, automotive, aerospace, dental and medical industries, education. , civil engineering and other fields.

Existing methods for accumulating the above-mentioned powdery metal powder or non-metal powder stack into a three-dimensional entity include Selective Laser Sintering (SLS) and Selective Laser Melting (SLM), the above two The powder is heated to its sintering temperature or melting point to sinter or melt the powder into a film having a specific thickness. After repeated sintering or melting, a multilayer stacked film can be produced to form a three-dimensional entity. However, the above sintering temperature or melting point often needs to be thousands of degrees. If the powder is directly heated from a normal temperature to a thousand degrees, during the rapid temperature rise, the temperature gradient in the powder body will generate thermal stress and accumulate in the material. Causes three-dimensional solids to curl, deform, and even rupture. Therefore, selective laser sintering (SLS) and selective laser melting (SLM) usually require the use of a preheating device to preheat the powder by reducing the temperature of the powder slightly below its sintering temperature or melting point. The temperature gradient within the small powder increases the sintering efficiency. In the prior art, selective laser sintering and selective laser melting mostly use a thermal coupler, a laser source, a near-infrared light source, etc. to preheat the powder, and then the heating There is still room for improvement in the heating efficiency and heating uniformity of the powder. In other words, how to preheat the powder more efficiently and evenly is one of the problems that researchers are currently trying to solve.

The novel creation provides a three-dimensional printing apparatus that can efficiently and uniformly heat the powder.

The three-dimensional printing device of the embodiment of the present invention includes an electromagnetic wave generation a preheating stage and an optical scanning element. The electromagnetic wave generator is adapted to generate an electromagnetic wave to define an electromagnetic wave preheating zone, and the preheating stage is disposed in the electromagnetic wave preheating zone. The preheating stage is adapted to carry a powder, and the preheating stage absorbs electromagnetic waves to raise the temperature of the powder to a first temperature. The optical scanning element is adapted to emit a beam of light onto the powder to locally heat the powder to a second temperature, and the first temperature is lower than the second temperature, and the second temperature is the sintering temperature or melting point of the powder.

In an embodiment of the present invention, the preheating stage has a bearing surface carrying a powder. The preheating stage is adapted to move in a direction that is parallel to the normal to the bearing surface.

In an embodiment of the present invention, the three-dimensional printing apparatus further includes a powder supply module that supplies the powder to the preheating stage.

In an embodiment of the present invention, the powder supply module has a spray end, and the spray end is adapted to spray the powder to the preheating stage.

In an embodiment of the present invention, the powder supply module includes a drum and a storage stage. The storage stage includes a bottom surface for moving in a pushing direction, and the roller rolls in a rolling area along a rolling direction. The storage stage and the preheating stage are located in the rolling area, and the rolling direction is perpendicular to the pushing direction.

In an embodiment of the present invention, the preheating stage includes a container for holding a powder.

In an embodiment of the present invention, the optical scanning element includes a laser source that provides a light beam and a scanning unit. The scanning unit is disposed on the light path of the light beam, and the scanning unit is located between the laser light source and the preheating stage.

In an embodiment of the present invention, the electromagnetic wave generator is a microwave generator.

Based on the above, the preheating stage located in the electromagnetic wave preheating zone of the three-dimensional printing device of the presently-created embodiment can absorb the electromagnetic wave to increase the ambient temperature of the powder and directly preheat the powder, thereby reducing the beam. The effect of temperature gradient on the heating of the local powder to the sintering temperature or melting point, thereby improving the overall sintering efficiency and yield.

The above described features and advantages of the present invention will become more apparent and understood from the following description.

D1, d2‧‧‧ direction

H‧‧‧热能

L1‧‧‧ Beam

P1, k1‧‧ path

S1, S2‧‧‧ electromagnetic waves

100, 100B, 100C‧‧‧ three-dimensional printing device

110, 110B, 110C‧‧‧ preheating stage

112C‧‧‧ stage

113, 113B, 113C‧‧‧ bearing surface

114B‧‧‧ Sidewall

115B‧‧‧ inner surface

116B‧‧‧ Carrying trough

120, 120B‧‧‧ electromagnetic wave generator

121, 121B, 121C‧‧‧ electromagnetic wave preheating area

130‧‧‧ Optical scanning components

132‧‧‧Laser light source

134‧‧‧ scanning unit

200, 200A, 203B, 200C, 203C‧‧‧ powder

201B, 205B‧‧‧ powder layer

210A‧‧‧Electromagnetic wave absorption powder

220A‧‧‧ceramic powder

300‧‧‧ powder supply module

301‧‧‧ spray end

310C‧‧‧Roller

311C‧‧‧ side

320C‧‧‧Storage carrier

321C‧‧‧ bottom

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic illustration of a three dimensional printing apparatus in accordance with a first embodiment of the present invention.

2 is a schematic view of a sintered powder according to a second embodiment of the present invention.

3A through 3C are schematic views of a three-dimensional printing apparatus in accordance with a third embodiment of the present invention.

4 is a schematic diagram of a three-dimensional printing apparatus in accordance with a fourth embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic illustration of a three dimensional printing apparatus in accordance with a first embodiment of the present invention. Referring to FIG. 1, in the first embodiment of the present invention, the three-dimensional printing apparatus 100 includes a preheating stage 110, an electromagnetic wave generator 120, and an optical scanning element 130. The electromagnetic wave generator 120 is adapted to generate an electromagnetic wave S1 to define an electromagnetic wave preheating region 121, and the preheating stage 110 is disposed in the electromagnetic wave preheating region 121. In this embodiment, the electromagnetic wave generator 120 is connected to the underheating stage 110, for example, but the novel creation is not limited thereto. In other embodiments, the electromagnetic wave generator 120 may be further configured to define an electromagnetic wave preheating area. 121 location.

In the first embodiment of the present invention, the preheating stage 110 is adapted to carry a powder 200, and the preheating stage 110 absorbs the electromagnetic wave S1 to raise the powder 200 to a first temperature. The optical scanning element 130 is adapted to emit a light beam L1 onto the powder 200 to locally heat the powder 200 to a second temperature, and the first temperature is lower than the second temperature, and the second temperature is the sintering temperature or melting point of the powder 200. . The light beam L1 is used to heat the powder 200 to a second temperature, wherein the first temperature is lower than the second temperature. Specifically, the three-dimensional printing apparatus of the present embodiment preheats the powder 200 to the first temperature by the preheating stage 110 that can absorb electromagnetic waves. After the powder 200 is preheated to the first temperature, the light beam L1 emitted from the optical scanning element 130 heats the local powder 200 to the sintering temperature or melting point of the powder 200. By means of two heatings, the powder 200 does not experience too much temperature difference during the heating from the first temperature to the second temperature. Therefore, after the three-dimensional printing apparatus 100 of the present embodiment sinters or melts the powder 200, excessive thermal stress is not generated during powder molding, and the overall production yield is improved.

In detail, in the present embodiment, the material of the preheating stage 110 includes, for example, silicon carbide (SiC), and the electromagnetic wave generator 120 is, for example, a microwave emission source for emitting a microwave for the preheating stage. 110 absorbs and heats, but the novel creation is not limited to this. In other embodiments, the material of the preheating stage 110 may further include ferrite, tantalum carbide, soot, carbon fiber, silicon nitride, carbonyl iron. , such as zinc oxide, other metal, non-metal or metal oxide suitable for absorbing microwaves and having high dielectric loss or magnetic loss, and absorbing electromagnetic waves emitted to the surface of the preheating stage 100 by the above materials, and The energy of the absorbed electromagnetic wave is converted into thermal energy by the dielectric loss or magnetic loss of the above material. Further, the electromagnetic wave generator may be a near-infrared light generator or a generator of other wavelength electromagnetic waves, and the material of the preheating stage may further include other metals, non-metals or metal oxides to absorb the electromagnetic wave generator. The material of the electromagnetic wave emitted. In the first embodiment of the present invention, the electromagnetic wave S1 emitted by the electromagnetic wave generator 120 preferably has a power of 200 watts to 1000 watts, and the electromagnetic wave S1 preferably has a frequency range of 0.3 GHz to 30 GHz, but the novel creation is not Limited to this.

On the other hand, in the first embodiment of the novel creation, the optical scanning element 130 includes a laser light source 132 that supplies the light beam L1 and a scanning unit 134. The scanning unit 134 is disposed on the light path of the light beam L1, and the scanning unit 134 is located between the laser light source 132 and the preheating stage 110. The optical scanning element 130 can selectively heat the powder 200 on a bearing surface 113 of the preheating stage 110. In detail, the laser light source 132 is, for example, a carbon dioxide laser source, a yttrium aluminum garnet (Neodymium-doped Yttrium Aluminium Garnet, Nd-YAG) laser source, fiber laser source, ultraviolet laser source or pulsed laser source, and scanning unit 134 is, for example, a dynamic mirror, thereby enabling lightning The laser beam L1 emitted by the light source 132 can be irradiated to a desired position. Specifically, the laser light source 132 of the present embodiment preferably provides a light beam having a power of 10 watts (Watts, W) to 100 watts and a spot diameter of 0.05 mm to 0.5 mm, and the scanning speed of the scanning unit 134. It is preferably from 50 to 500 mm per second, but the novel creation is not limited thereto.

In the first embodiment of the present novel creation, the powder heating method using the three-dimensional printing apparatus 100 includes providing the powder body 200 on the bearing surface 113 of the preheating stage 110, and then providing an electromagnetic wave S1 to the electromagnetic wave generator 120 to The stage 110 is preheated to heat the powder 200 to the first temperature by the preheating stage 110. The beam L1 is then supplied to the local powder 200, whereby the local powder 200 is heated to a second temperature and the local powder 200 begins to sinter or melt, but the novel creation is not limited thereto.

The three-dimensional printing device of the second embodiment of the present invention is similar to the three-dimensional printing device 100, except that the preheating stage 110 is not formed by an electromagnetic wave absorbing material, and the powder heated by the three-dimensional printing device is A sintered powder. 2 is a schematic view of a sintered powder according to a second embodiment of the present invention. Referring to FIG. 2, in the second embodiment of the present invention, the sintered powder 200A includes an electromagnetic wave absorbing powder 210A and a ceramic powder 220A. The electromagnetic wave absorbing powder 210A and the ceramic powder 220A are physically mixed in the sintered powder 200A, wherein the electromagnetic wave absorbing powder 210A is adapted to absorb the electromagnetic wave S1 and raise the temperature, thereby preheating the ceramic powder 220A to a first temperature. That is, as long as an electromagnetic wave S1 is supplied to the burning of this embodiment In the powder compact 200A, the electromagnetic wave absorbing powder 210A absorbs the electromagnetic wave S1 and transmits thermal energy h to the surrounding ceramic powder 220A, so that the ceramic powder 220A can be preheated to the first temperature.

Specifically, when the sintered powder 200A is placed, for example, in the electromagnetic wave preheating zone 121 of the three-dimensional printing apparatus 100 illustrated in FIG. 1, the electromagnetic wave S1 provided by the electromagnetic wave generator 120 can preheat the sintered powder 200A. To the first temperature. Therefore, the sintered powder 200A of the present embodiment can also provide a good sintering mode by physically mixing the electromagnetic wave absorbing powder 210A and the ceramic powder 220A in the sintered powder 200A, and the sintered powder 200A receives electromagnetic waves. Uniform heating can be achieved to achieve a good preheating effect, which can also increase yield during subsequent sintering.

In detail, the sintered powder 200A of the second embodiment of the present invention can be applied to a selective sintering method including providing a sintered powder 200A including an electromagnetic wave absorbing powder 210A and a ceramic powder 220A, followed by providing an electromagnetic wave. From S1 to the sintered powder 200A, the electromagnetic wave absorbing powder 210A of the sintered powder 200A absorbs the electromagnetic wave S1 and raises the temperature, thereby preheating the ceramic powder 220A to the first temperature. Next, a light beam is supplied to heat the partially sintered powder 200A to the second temperature, thereby sintering the partially sintered powder 200A. The first temperature is lower than the second temperature, that is, the first temperature is lower than the sintering temperature of the ceramic powder. In other words, when the sintered powder 200A is applied to the above-described three-dimensional printing apparatus 100, the partial sintered powder 200A can be heated to the second temperature when the light beam is irradiated to the partially sintered powder 200A. The sintering temperature of the ceramic powder 220A in the sintered powder 200A is the second temperature, and the ceramic powder 220A is preheated by electromagnetic waves. The effect of the sintered powder 200A does not generate excessive thermal stress and residual stress during molding after sintering or melting, thereby improving the overall yield.

In the second embodiment of the present novel creation, the main components of the ceramic powder 220A include zirconium dioxide (ZrO ₂ ), Yttria-stabilized zirconia (YSZ), and cerium oxide (Silicon oxide). Zirconium Silicate, Aluminum Oxide, Titanium dioxide (TiO ₂ ) or a combination thereof, but the novel creation is not limited thereto. On the other hand, the ceramic powder 220A in the present embodiment preferably has a weight percentage of between 60% and 98% in the sintered powder 200A. In the present embodiment, the main components of the electromagnetic wave absorbing powder 210A include tantalum carbide, ferrite, tantalum carbide fiber, carbon black, carbon fiber, tantalum nitride, carbonyl iron powder, zinc oxide or a combination thereof, but the novel creation is not Limited to this. On the other hand, the electromagnetic wave absorbing powder 210A in the present embodiment preferably has a weight percentage of between 2% and 40% in the sintered powder 200A. In other words, in the embodiment of the present invention, the material of the electromagnetic wave absorbing powder is converted into thermal energy by dielectric loss or magnetic loss, that is, at a normal temperature or a temperature lower than the sintering temperature, this embodiment The material of the electromagnetic wave absorbing powder has a characteristic of high dielectric loss or magnetic loss, so that the ceramic powder can be preheated by absorbing an electromagnetic wave.

In the present embodiment, the center particle diameter of the ceramic powder 220A is larger than the center particle diameter of the electromagnetic wave absorbing powder 210A, and the center particle diameter of the ceramic powder 220A is preferably between 200 nm and 60 μm, and the electromagnetic wave absorbing powder 210A The central particle size is preferably between 20 nm and 10 microns. Therefore, in detail, the embodiment The selective sintering method can provide the sintered powder 200A by physically mixing the above-mentioned preferred electromagnetic wave absorbing powder 210A and ceramic powder 220A, so that the sintered powder 200A can be uniformly preheated to the first temperature when receiving electromagnetic waves. The partially sintered powder 200A is heated to a second temperature by irradiation to a light beam and achieves a good sintering effect. For example, the above-mentioned center particle diameter refers to the intermediate number of the diameters of all of the particles in a powder containing a plurality of particles.

Referring to FIG. 1 , in the first embodiment of the present invention, the three-dimensional printing apparatus 100 further includes a powder supply module 300 that supplies the powder 200 to the bearing surface 113 . More specifically, in the present embodiment, the powder supply module 300 has a spray end 301 for spraying the powder 200 to the preheating stage 110. That is, the powder supply device 300 can form a powder layer on the bearing surface 113 of the preheating stage 110 along the path P1, and the powder layer is parallel to the bearing surface 113, but the novel creation is not limited to this.

3A through 3C are schematic views of a three-dimensional printing apparatus in accordance with a third embodiment of the present invention. Referring to FIG. 3A, the three-dimensional printing apparatus 100B of the third embodiment of the present invention sprays the powder to the bearing surface 113B of the preheating stage 110B by the spraying end 301 of the powder supply module 300 and forms a powder layer 201B. On the bearing surface 113B, the powder layer 201B is parallel to the bearing surface 113B. Next, an electromagnetic wave S1 is supplied from the electromagnetic wave generator 120B in the preheating stage 110B to define an electromagnetic wave preheating area 121B in which the preheating stage 110B is disposed.

In the present embodiment, the preheating stage 110B includes a container, that is, the preheating stage 110B further includes a plurality of side walls 114B, and the inner surface 115B of the side walls 114B The bearing surface 113B is joined and the container is formed. Therefore, in addition to providing a larger contact area to preheat the powder layer 201B, the preheating stage 110B of the present embodiment can more stably accommodate the powder forming the powder layer 201B. In detail, the inner surface 115B and the bearing surface 113B form a bearing groove 116B, which provides a powder accommodation space which is more complete and can be more uniformly preheated. On the other hand, the preheating stage 110B described above can be moved along the direction d1, and the direction d1 is parallel to the normal to the bearing surface 113B.

In detail, referring to FIG. 3A and FIG. 3B, after the powder layer 201B is preheated to the first temperature via the preheating stage 110B that absorbs the electromagnetic wave S1, the optical scanning element 130 supplies a light beam L1 to the local powder. The light beam L1, for example, heats the local powder 203B to a second temperature higher than the first temperature and completes the sintering of the powder layer 201B, and the preheating stage 110B moves in the direction d1. Next, the powder supply module 300 sprays the powder onto the powder layer 201B and forms a powder layer 205B. That is, the spray end 301 of the powder supply module 300 of the present embodiment can be fixed to form a powder layer along the direction d2, and the spray end 301 sprays the powder, for example, along the path k1.

Referring to FIG. 3C, after the powder layer 205B is formed, the light-emitting element 130 further supplies the light beam L1 to heat the local powder of the powder layer 205B to the second temperature. The second temperature is not limited to the sintering temperature of the ceramic powder 205B, for example, a ceramic powder. When the powder includes the metal powder, the second temperature may be the melting point of the metal powder, and the novel creation is not limited thereto. That is, the three-dimensional printing apparatus 100B of the third embodiment preheats the powder layers 201B, 205B by the preheating stage 110B, and further heats it by the optical scanning element 130, and thus can be applied to selective laser sintering. Or selective laser melting technology.

4 is a schematic diagram of a three-dimensional printing apparatus in accordance with a fourth embodiment of the present invention. Referring to FIG. 4, in the fourth embodiment of the present invention, the powder supply module 300C of the three-dimensional printing apparatus 100C includes a drum 310C and a storage stage 320C. The storage stage 320C includes a bottom surface 321C for moving in a pushing direction (that is, a direction d1), and the storage stage 320C accommodates the sintered powder 200C. The drum 310C rolls along a rolling direction d2 in a rolling area A, and the rolling direction d2 is parallel to the bearing surface 113C on a stage 112C and perpendicular to the direction d1, and the storage stage 320C and the stage 112C are located in the rolling area A. .

In the present embodiment, the sintered powder 200C is similar to the sintered powder 200A described above, and includes at least one electromagnetic wave absorbing powder and at least one ceramic powder, so that an electromagnetic wave S2 is generated by using an electromagnetic wave generator (not shown). After the electromagnetic wave preheating zone 121C is defined, the sintered powder 200C can absorb the electromagnetic wave S2 by the electromagnetic wave absorbing powder therein and uniformly and well preheat the ceramic powder, thereby providing a good selective sintering effect or selectivity. Melting effect.

That is, the three-dimensional printing apparatus 100C of the present embodiment, for example, first moves the bottom surface 321C of the storage stage 320C in the direction d1 to push the sintered powder 200C out, and then pushes the sintered powder to be pushed out by the drum 310C. The body 200C is pushed from the storage stage 320C to the bearing surface 113C to form a powder layer, and since the sintered powder 200C includes electromagnetic wave absorbing powder, the sintered powder 200C on the storage stage 320C, the drum 310C, and the bearing surface 113C can be A good warm-up effect is obtained after the electromagnetic wave preheating region 121C receives the electromagnetic wave S2.

Further, in this embodiment, the stage 112C may further include preheating. The stage 110C is for absorbing the electromagnetic wave S2 to preheat the sintered powder 200C to the first temperature. The storage stage 320C may further include the same material as the preheating stage 110C, and the material of the side surface 311C of the drum 310C is also the same as that of the preheating stage 110C. Therefore, the three-dimensional printing apparatus 100C of the present embodiment is absorbed. The electromagnetic wave S2 can provide a highly efficient and uniform preheating effect, thereby allowing the optical scanning unit 130 to provide a light beam to sinter or melt the local powder 203C. In the above embodiment, the first temperature and the second temperature have a temperature difference between 200 degrees Celsius and 600 degrees Celsius, so that the preheated powder is irradiated by a light beam. When it does not cause excessive temperature difference, it can be applied to the technology of selective laser sintering or selective laser melting to solve the cracks, cracks or deformations generated during molding. In the above-described embodiment of the present invention, the second temperature is, for example, between 500 degrees Celsius and 1000 degrees Celsius, depending on the material in the powder, and the novel creation is not limited thereto.

In summary, the preheating stage of the electromagnetic wave preheating zone in the three-dimensional printing device of the embodiment of the present invention can rapidly raise the ambient temperature of a powder by absorbing electromagnetic waves emitted by the electromagnetic wave generator. At the same time, since the powder to be sintered, for example, ceramic powder in the powder, increases the electromagnetic wave absorbing ability of the powder to be sintered while raising the temperature, the electromagnetic wave provided by the electromagnetic wave generator is heated by a preheating stage and heated to a specific The absorption of the powder of the temperature can be preheated to the first temperature more efficiently and uniformly. When the beam is irradiated to the powder partially preheated to the first temperature, the temperature gradient effect generated when the powder is heated to the second temperature and sintered or melted can be reduced, and can be applied to selective laser sintering or selective Laser melting technology Improve overall efficiency and yield.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the novel creation, and any person skilled in the art can make some changes without departing from the spirit and scope of the novel creation. Retouching, the scope of protection of this new creation is subject to the definition of the scope of the patent application attached.

L1‧‧‧ Beam

P1‧‧ path

S1‧‧‧Electromagnetic waves

100‧‧‧3D printing device

110‧‧‧Preheating stage

113‧‧‧ bearing surface

120‧‧‧Electromagnetic wave generator

121‧‧‧Electromagnetic wave preheating zone

130‧‧‧ Optical scanning components

132‧‧‧Laser light source

134‧‧‧ scanning unit

200‧‧‧ powder

300‧‧‧ powder supply module

301‧‧‧ spray end

Claims (8)

A three-dimensional printing device comprises: an electromagnetic wave generator adapted to generate an electromagnetic wave to define an electromagnetic wave preheating zone; a preheating stage adapted to carry a powder, the preheating stage being disposed in the electromagnetic wave pre Absorbing the electromagnetic wave to heat the powder to a first temperature; and an optical scanning element adapted to emit a light beam onto the powder to locally heat the powder to a second temperature, and the first A temperature is lower than the second temperature, and the second temperature is a sintering temperature or a melting point of the powder. The three-dimensional printing apparatus according to claim 1, wherein the preheating stage has a bearing surface for carrying the powder, and the preheating stage is adapted to move in a direction, and the direction is parallel to The normal of the bearing surface. The three-dimensional printing apparatus according to claim 1, further comprising a powder supply module for supplying the powder to the preheating stage. The three-dimensional printing apparatus according to claim 3, wherein the powder supply module has a spray end adapted to spray the powder to the preheating stage. The three-dimensional printing apparatus according to claim 3, wherein the powder supply module comprises a drum and a storage stage, the storage stage includes a bottom surface for moving along a pushing direction, The drum rolls in a rolling direction along a rolling direction, the storage stage and the preheating stage being located in the rolling area, the rolling direction being perpendicular to the pushing direction. The three-dimensional printing apparatus according to claim 1, wherein the preheating The stage includes a container to contain the powder. The three-dimensional printing device of claim 1, wherein the optical scanning element comprises: a laser light source adapted to provide the light beam; and a scanning unit disposed on the light path of the light beam and the scanning unit Located between the laser source and the preheating stage. The three-dimensional printing apparatus according to claim 1, wherein the electromagnetic wave generator is a microwave generator.