3D printing, a new industry of rapid prototyping technology, has attracted people's attention gradually, and has become the focus of scholars at home and abroad. It is made seamlessly, rapidly, and is suitable for manufacturing various complex structure products. It is different from traditional production and processing methods. At the same time, 3D printing is also a comprehensive technology integrating the knowledge of computer science, material science, machining technology and scanning science, and is an important sign of the comprehensive development of modern society.

1、 The characteristics and principles of 3D printing technology

The difference between 3D printing technology and traditional printer is that: first, it is not like traditional printer, but is made of powder or silk plastic, glass, flour and nylon as printing materials. Second, the reason why 3D printer becomes "3D" is that its achievements are not limited to text form, but can transform the virtual 3D graphics in the computer connected with it into concrete objects. Therefore, 3D printing is a high-tech technology for material addition manufacturing and rapid prototyping. The main advantages include: production can be carried out at any time, especially when the parts are in small quantities, which avoids the cost waste caused by frequent start-up of production lines; the principle of 3D printing technology determines that it is not restricted by product structure in the manufacturing process, and can produce extremely complex physical objects, which is difficult to realize by traditional machining methods; Compared with the traditional method of reducing material, the material increase manufacturing reduces the waste of materials, thus effectively reducing the processing cost.

The basic principle of 3D printing technology is divided into three steps: first, the 3D electronic model of the object to be printed, including its shape and dimensions, should be designed in the computer. This step can be realized by some existing drawing software, such as CAD, 3DMAX, etc. Secondly, on the premise of connecting with computer, 3D printer will segment the 3D graphics information, and the density of segmentation is related to printer and material. Finally, according to the information of each layer plane after segmentation, the 3D printer automatically determines the printing path and prints it layer by layer until the final forming. According to the different types of machines, the printing method can melt the material by means of high temperature or laser lamp, and then pile up and form one layer by another; or glue can be used to glue the material layer by layer.

2、 The application status of 3D printing technology

In recent years, with the continuous improvement of 3D printing technology, 3D printers are applied in more and more fields, including mechanical manufacturing, biomedical, construction, archaeology and food industry.

1. mechanical manufacturing field. With the advent of globalization, the demand of products is becoming more and more diversified, which promotes the transformation of manufacturing mode of multi varieties, small batch or even single-piece production. The advantage of 3D printing technology, which can print complex structural parts and low starting cost, brings opportunities for the development of single piece production mode.

2. biomedical field. In recent years, some countries have made use of 3D printing technology to produce organs without any rejection. In addition, bone printing and tooth printing have been realized successively, which has made certain contributions to the progress of medicine.

3. construction industry. At present, 3D printing technology is mainly used in the construction industry to make models. The architectural designer can present the architectural model by 3D printer and complete the corresponding function evaluation. Compared with other methods of manufacturing model, the architecture designer has the advantages of faster speed and lower production cost. In addition, 3D printing technology can also create houses that are directly for people to live in.

4. archaeological field. When some ancient Chinese objects are damaged, such as cracks or cracks, they can be detected and repaired by 3D printing technology.

5. food industry. At present, there are already applications of 3D printer printing simple food, such as pancakes and other foods. This technology can not only reduce the manual labor, but also print out the physical appearance more refined, and the taste of common practice is almost no different.

3、 The development prospect of 3D printing technology

With the development of society and the progress of science and technology, 3D printing will also be paid more and more attention. Its technical level will also be improved and its functions will be improved. Its development prospects include the following aspects:

1. diversification of printing materials

Materials are the basis of printing products, and the development of 3D printing must have the corresponding performance of the use of materials as the prerequisite. According to statistics, the current share of this technology in manufacturing industry is very small, one of the important reasons is the limitation of the type of printing materials. [5] Therefore, the future 3D printing materials will be towards a diversified trend, and the development of new materials can make printers suitable for the production and manufacture of more products.

2. innovation of printing technology

If the diversification of materials is the foundation of 3D printing development, the innovation and improvement of technology is the key to the development of 3D printing. This is mainly reflected in the accuracy, printing speed, type and intelligent level of the printed products.

3. extension of application scope

At present, although 3D printing has been applied in many fields, it is not widely used and immature. For example, only a few kinds of food are used in 3D printing technology; its application in the fields of architecture and medicine has great limitations; some industries have not been involved in the application of this technology for various reasons. Therefore, with the rapid development of science and technology, 3D printing will be widely used in all walks of life and play a great role in more fields.

4. printer price control

Although compared with traditional methods, 3D printing saves materials and shortens production time, thus reducing the cost of processing products to a certain extent. But at present, the price of 3D printer itself is still relatively expensive, especially for printers with strong functions and high precision requirements, which is very difficult for some small enterprises. Therefore, with the continuous improvement of technology and materials, the production cost of 3D printer will be reduced, so that the equipment is no longer a difficult problem in technology application.

4、 Conclusion

3D printing technology overcomes the limitation of traditional production mode for a long time, which will be another great leap in the history of technology in China and even the world. It brings new opportunities for people's production and life and the development of society. At the same time, because it is still in the emerging and initial stage, and not mature in all aspects, the government is also increasing the efforts to promote the development of 3D printing from policy and economy, encouraging people to actively explore and strive to make contributions to human civilization as soon as possible.