Field of Invention

There are several different types of Additive Manufacturing (AM) depending on the type of material to be produced. The common point of all of these methods is that the object to be produced is drawn in any CAD program and divided into layers to be printed on a 3D printer. The AM method includes various technologies such as Selective Laser Sintering (SLS), Fusion Deposition Modeling (FDM), Fusion Filament production (FFF), Stereolithography (SLA), Electron Beam Melting (EBM) and Digital Light Polymerization (DLP) for the production of complex, high- volume net- shape components.

State of the Art of the Invention (Prior Art)

Although there are many technologies in 3D printing of ceramics, the proportion of ceramic powder does not exceed 60% by volume, except for bulk solid-based technologies such as SLS and SLM, which use laser beams that causes residual stresses.

Thermal gradients under rapid laser heating and cooling rates within ceramic parts keeps to be an important factor inducing defects such as cracks and distortions. Although preheating the powder beds can help moderating this phenomenon, the high melting points of ceramics place more strain on the manufacturing process. The rough surface quality of ceramic parts after processing, undesirable porosity and large shrinkage also limit their application areas.

In addition, one of the biggest limitations of SLS today is the lack of materials that can be produced in powder form needed for this printing method, which affects the low variety of materials available.

Brief Description and Aims of the Invention Although there are many technologies in 3D printing of ceramics, the proportion of ceramic powder does not exceed 60% by volume, except for bulk solid-based technologies such as Selective Laser Sintering (SLS) and Selective Laser Melting (SLM), which use laser beams that causes residual stresses. Thermal gradients under rapid laser heating and cooling rates within ceramic parts keeps to be an important factor inducing defects such as cracks and distortions. Although preheating the powder beds can help moderating this phenomenon, the high melting points of ceramics place more strain on the manufacturing process. The rough surface quality of ceramic parts after processing, undesirable porosity and large shrinkage also limit their application areas. In addition, one of the biggest limitations of SLS today is the lack of materials that can be produced in powder form needed for this printing method, which affects the low variety of materials available.

Both the FDM and SLA techniques are limited to polymeric materials only, whereas the subject matter of the present invention is both a new technique in this field and offers reliable use for metal and ceramic materials. On the other hand, this method is both inexpensive and easy to use.

Definitions of Drawings Explaining the Invention

The figures prepared to better explain the three dimensional printer developed with this invention are explained below.

Figure 1 - Perspective view of the three dimensional printer.

Figure 2 - Side view of the three dimensional printer.

Figure 3 - Side view of the feeding unit

Definition of Elements/Pieces/Parts Composing the Invention

To better explain the three dimensional printer developed with this invention, the parts/pieces/elements in the figures prepared are numbered separately and the explanation of each number is given below.

1. Motor 2. Paste mixing unit

3. Printer head

4. Transmission organ (Extruder screw)

5. Spiral spring

6. UV source

7. Control screen

8. Feeding Motor

9. Feeding System

10. Feeding Hose

Detailed Description of the Invention

This study is briefly a new technique for new 3D additive manufacturing methods for ceramic, metal and composite materials. According to this technique, in the first stage, a photosensitive resin (Photopolymer resin) is mixed with ceramic powder or metal powder. In this method, the ceramic or metal powder ratio can be increased to 80-90%, unlike other methods. The mixture, which is made to the consistency of paste, can be pressed on a flat surface with the help of a spiral using a transmission organ like a hose. In this method, the infrastructure of the FDM (Fusion deposition modelling) 3D printer can be used. At this point, the paste-like mixture is connected to the printer head with a feeding hose (10) such as a plastic hose. Normally the FDM 3D printer has a heater. In this method, the heater used in FDM is deactivated and instead a single screw, push extruder is used. On the other hand, a powerful UV source is placed just under the extruder. The extruder spiral presses the mixed paste into the hose, and the paste that comes out of the extruder nozzle hardens as soon as it is exposed to UV light.

In this study, part of the FDM technique for printing ceramic and metal composites, mixing ceramic or metal powder and photosensitive resin in paste consistency and using UV light is essential and this is a different point from other methods.

This invention covers the design and production of 3D printers for ceramic or metal composite production. The printer consists of the motors (1) moving on the X, Y and Z axes, the paste mixing unit (2), the spiral spring (5) to press the raw material to the printer head, the printer head (3), the UV source (6) under the printer head screw (4) and the control screen (7).

The three dimensional printer using Fusion Deposition Modelling has the following in its most basic form;

• Motors (1) that move the plate on which the part to be 3D printed along the X, Y, Z axes is placed,

• The paste mixing unit (2), where the composite mixture is prepared,

• Printer head (3), which is the nozzle part of the extruder and where the composite mixture is transferred to the printing plate,

• Feeding hose (10) that transmits the composite mixture taken from the paste mixing unit to the printer head,

• Feeding motor (8) that enables the composite mixture to be transmitted to the feeding hose (10),

• Transmission organ (extruder screw) (4) that provides the transfer of the pastelike mixture to the printer head,

• Spiral spring (5), which ensures that the extruder nozzle (printer head) is pressed onto the product printing platform,

• UV source (6), which enables the resin (composite mixture) used for the product to harden and is located under the screw of the printer head,

• Control screen (7) where all functions of the 3D printing device are controlled.

The related composite mixture can also be prepared in another device and transferred to the printer head (3) with the help of an extruder. The UV source (6) comprises UV lamps radiating in the entire visible region, and the control screen (7) means the computer hardware and screen on which all functions of the 3D printing device are controlled.