Development status and future trends of 3D printing manufacturing technology

On June 14th, the “Weweek 2019 (15th) China Laser Technology and Industrial Application Forum” hosted by OFweek Laser Network was hosted by China High-Tech Portal OFweek Veco Network and High-Tech Association. It was officially opened at JW Marriott Hotel Shenzhen Qianhai Overseas Chinese Town. Held.

In this laser technology and industrial application forum, Professor Yang Yongqiang from South University of Technology brought a keynote speech on “The Future of 3D Printing Manufacturing Technology”. He introduced the development of laser and 3D printing, the strategic significance of 3D printing, the status quo and typical processes.

OFweek 2019 (fifteenth) China Laser Technology and Industrial Application Forum successfully held

Professor Yang Yongqiang of South China University of Technology

The following is the speech of Professor Yang Yongqiang, and the editor of OFweek Laser Network has done the finishing and editing without changing the original intention.

Original speech:

To introduce to you, 3D printing technology and laser technology have appeared in the last century. In 1958, the concept of laser appeared. The first laser appeared in 1960. The concept of 3D printing actually appeared in the mid-1980s, so the history of 3D printing is shorter, and it has only been more than 30 years.

We divide manufacturing technology into three categories, one is the manufacture of equal materials, the second is the reduction of materials manufacturing, and the third is the additive manufacturing, which is what we call 3D printing. The typical representative technology for the manufacture of equal materials is casting and forging. This process has actually appeared more than 3,000 years ago and it has a very long history of development. The reduction of material manufacturing is represented by the European industrial revolution. The machine tools that have appeared since then, and now our CNC machine tools have a history of 300 years, so the technology in the field of processing and manufacturing is very mature. Additive manufacturing (3D printing technology) has only been 30 years old, but its development is very rapid.

Today, I mainly explain the additive manufacturing part of metal materials, that is, 3D printing technology. In 2001-2002, 3D printing was still in the laboratory stage. At that time, the fiber laser was still immature, and only the semiconductor laser could be used as the initial metal. 3D printing.

From development to the present, 3D printing has been divided into several categories. From non-metal, liquid to solid to powder, it should be said that the high-end technology in the most advanced 3D printing technology is laser as heat source technology, including laser stereoforming, laser selective sintering and laser selective melting. Among them, in the field of metal parts, 3D printing is divided into laser technology as a heat source, including laser-selected laser-distributed area, laser-shaped three-dimensional forming of melted powder feeding. In addition to the laser, the number of electrons in the high-energy beam, as well as the plasma, and even the arc can be used as a heat source for 3D printing.

At the national level, the state is very supportive of the development of 3D printing. In 2015-2016, it proposes the promotion plan for the development of the national additive manufacturing industry. 2017-2020 is the main development plan for upgrading additive manufacturing, mainly around the materials for metal additive manufacturing. Equipment made of metal and metal based on laser and electron beam.

In recent years, Guangdong Province has attached great importance to laser and additive manufacturing, and has developed four national “laser and additive manufacturing” major science and technology projects in 2018-2019, with an average of 20 million each. The dust has already ended. In this year's plan, whether it is laser or 3D printing, the support from the state to the local government has increased, especially in Guangdong Province.

In the additive manufacturing design, it is stacked from point to line, from line to surface, layer by layer, so it is not subject to traditional manufacturing processes and manufacturing resources, focusing on form creativity and functional innovation, changing design in manufacturing. Under the premise, the pursuit of creation has no limits. In the past, only designers could do the work of creation. Now we can paint, and everyone can be a maker or a creator. So, 3D printing brings us new opportunities.

In terms of product structure optimization, the material used in the material reduction in the past is a solid material, and there can be no defects, and then processing, and removing the unnecessary places is the material we need. But in many areas, especially aerospace, including our usual industrial fields, not necessarily using so many materials, or its strength requirements are not so high. Therefore, such a mesh structure upgrade inside a lightweight porous structure is highly desirable.

Today's design tomorrow will provide a very convenient condition for 3D printing. What is today's design? In the past, we designed cylinders for engines like cars, and wanted to make a new engine, from design to mold opening to sand casting, and finally made the metal and then went to the test. The cycle was very long and the cost was very high. Now we can draw it out and print out a model, you can go directly to the test. I can only do a few models in the past year, and I can do a lot now. You can see that the application of 3D printing in the automotive field is very mature.

Compared with traditional machining and milling, 3D printing can be used as a material stacking manufacturing method to manufacture various complex shapes (not affected by spatial accessibility), and can fully utilize the material's performance ratio, which is one of the main ways of green manufacturing in the future. . 3D printing brings convenience to our designs, including in-house complex cavity forming and integrated molding. For example, to be a mechanism, a universal joint requires 12 parts to be assembled. As long as 3D printing considers where it is connected, it can be printed directly. He is not a part, it is a structure, so in the future we can even connect the motor to it and it can move, it is a machine.

3D printing applications are very extensive, and currently used in aerospace, automotive molds, consumer electronics, education, cultural creativity, jewelry, medical and other fields. For example, aerospace components are complex, require high weight and high price, so they are the most urgent and successful for 3D printing applications.

In the automotive sector, in addition to engine development, many parts of the car, even now the emergence of new energy vehicles, have brought a lot of new things, or very new designs. We consider lightweight, consider its structure, its various properties, this is some of the parts that 3D printing currently does, it used to be built in the past may have to be cast, or to be processed, then now we use 3D printing To do it, it can be done very simply, or it is lightweight.

In terms of molds, the rapid response of 3D printing technology and the high degree of freedom of molding characteristics have brought about tremendous changes in the mold manufacturing industry. Reduce cycle time, reduce costs, lower barriers, increase life and customize.

In terms of education, there is now a lot of practical demand for technology in 3D printing education in universities including primary and secondary schools. Because everyone is not familiar with this. There are also cultural ideas, and jewelry and consumer electronics are also heavily used in 3D printing technology.

In the medical field, we know that there are some implants in the human body, and there are a lot of restorations. It is not a regular shape. It is very difficult to use machining in the past, and 3D printing brings us a very Convenient tool.

At present, the two most successful applications, one is aerospace and the other is medical, and the current market share of these two fields is very large.

At present, 3D printing is roughly divided into five categories, the first type is powder/filament material high energy beam sintering or melt forming; the second type is filament material extrusion hot melt forming; the third type is liquid resin photocuring forming; fourth The class is liquid jet forming; the fifth type is sheet/sheet bonding/welding forming of paper, plastic film or composite material. The most typical of these processes is laser-selective sintering, which is mainly made of nylon plastic polymer materials. Of course, there are also some metal materials. Laser selective melting is a 3D printing technology for metal parts. This technology has revolutionized us, so some people say that 3D printing can lead the third industrial revolution. Germany regards 3D printing as a core technology in intelligent manufacturing in Industry 4.0.

South China University of Technology has been developing 3D printing technology for a long time, and I have entered the field of 3D printing since 2004. In 2004, South China University of Technology developed the first domestic laser melting and rapid manufacturing equipment DiMetal-240, and later developed a variety of equipment. From 2013 to 2016, our two companies in Guangdong Province also carried out industrialization. After these stereotypes, we are now starting to make products and do a good job. We have a large number of patents in this field, including invention patents and practical information patents.

We are in a leading position in many fields in the world, including aerospace, automotive parts, etc. For example, multi-material 3D printing equipment can have four materials, that is, we can print four materials in 3D printing. Do, for example, each layer is different, you can do two consecutive layers, you can do it. Record materials and composite materials. So in the field of application, in fact, we have done a lot of medical applications, and dentistry has shared results with many hospitals.

Our multi-material 3D printing equipment is also in a leading position in China. It develops a variety of metal 3D printing equipment to meet the requirements of printing a variety of metal materials at the same time. It can form complex functions with different materials in different parts at one time. Components.

The development of 3D printing is a trend. In addition to the automotive sector, there are some large-scale structural buildings that have better applications. It can be seen that 3D printing has a very large impact on our manufacturing industry.