When it comes to manufacturing in recent years, 3D printing, 3D printers, 3D printing, Rapid Prototyping, Rapid Manufacturing, digital manufacturing, and so on, are several hot words. These nouns like a tornado, as if overnight in academia politics, media, finance, manufacturing has aroused billows. But how much do you think about these concepts? If you're not sure, there's an article here that can parse these terms in a comprehensive and complete way, so that people really understand "what is Rapid Prototyping" and "what is Rapid Manufacturing" .
Part 1: Concept
Rapid Prototyping (RP) was born in the late 1980s. It is a new technology based on the material accumulation method. It is considered to be an important achievement in the manufacturing field in the past 20 years.
It is a set of mechanical engineering CAD reverse engineering technology layered manufacturing technology numerical control technology material science laser technology, can automatically and directly, quickly and accurately transform the design prototype for a certain function or production parts directly, making, so as to prototype new design ideas to the check etc. provides a means to achieve a high efficiency and low cost.
At present, the media used to Rapid Prototyping technology called "3D printing" or "three-dimensional printing" is more vivid, but in fact, "3D printing" or "three-dimensional printing" is a branch of Rapid Prototyping, Rapid Prototyping can only represent part of the process.
Rapid Manufacturing (RM). In broad sense, the narrow sense is a new concept of manufacture of sintered Rapid Prototyping technology based on laser powder, a branch of the RPRapid Prototyping actually belongs to the technology, it refers to the electronic data directly automatically fast, flexible and has low manufacturing into the. Rapid Manufacturing, compared with the general Rapid Prototyping technology, is that it can directly produce the final product, and can adapt to the manufacture of individual products from single product manufacturing to batch production.
In a broad sense, RMRapid Manufacturing can include fast tooling technology and CNC machining technology.
Additive Manufacturing(AM) is an international favorite to include RP and RM technologies. In 2009 the United States established the ASTM F42 Committee, AM will be defined as: "Process of joining mat-erials to make objects from 3D model data usua-lly layer, upon layer, as opposed to subtractive manufacturing methodologies".
Part 2: Several mainstream Rapid Prototyping process forming principle advantages and disadvantages
1. Stereolithography (SLA)
This SLA technology was prepared with photosensitive resin, UV laser under computer control according to the predetermined parts of each slice section contour for trajectory of the liquid resin even point scanning, scanning is resin thin area of the photo polymerization, a thin section forming parts.
When the layer is cured, the moving table is coated with a new layer of liquid resin on the surface of the previously solidified resin so that the next layer can be scanned and solidified.
The newly solidified layer is firmly bonded to the previous layer, so repeated until the entire part of the prototype is finished.
American 3DSYSTEMS was the first company to introduce this process. The technology is characterized by high accuracy and high smoothness, but the material is relatively brittle, the running cost is too high, the post-processing is complex, and the operator requires higher. Suitable for verification of assembly design process.
2.3Dimension Printing (3DP)
Its biggest characteristic is miniaturization and easy to operate, more used in commercial, office, research and personal studio environment. According to the different ways of printing, 3DP 3D printing technology can be divided into thermal explosion three dimensional printing (representative: 3D Systems's Zprinter series - formerly ZCorporation company, Systems company has been acquired by 3D), piezoelectric three-dimensional printing (representative: the United States 3D Systems company ProJet series and was recently Stratasys the acquisition of Objet in Israel, 3D printing equipment), DLP projection (3D printing: German Envisiontec, Ultra, Perfactory etc.).
The principle of thermal explosion of 3D printing technology is the powder from a storage barrel to send out certain components to the drum will send powder in processing platform covered with a thin layer of material, the print head in accordance with 3D computer model slice obtained after 2D layer information ejected standing agent, powder stick. When the machine is finished, the processing platform automatically drops a little, the storage barrel rises a little, and the scraper pushes the powder onto the work platform from the raised storage bucket and pushes the powder flat, so that the desired shape can be obtained in such a cycle. The technology is characterized by its speed (6 times the cost of other processes) and its low cost (1/6 of other processes). The disadvantage is that the accuracy and surface finish are low. The Zprinter series is the world's only 3D printing facility capable of printing full color parts.
Piezoelectric three-dimensional printing, similar to the traditional two-dimensional inkjet printing, you can print ultra-high precision sample, suitable for small, fine parts of Rapid, Prototyping. Compared with SLA, the equipment maintenance is simpler, the surface quality is good, and the Z axis accuracy is high.
The forming principle of DLP projection three-dimensional printing technology is the use of direct light molding technology (DLPR) the photosensitive resin molding, CAD data stratification and the establishment of supporting by computer software, and then output the black-and-white Bitmap file. Each layer of the Bitmap file is projected onto the worktable by a DLPR projector to solidify it. DLP projection three dimensional printing advantages: the use of machines when the factory is equipped with software, you can automatically generate support structures, and print the perfect three-dimensional components. Compared to other equipment in the Rapid Prototyping field, the unique voxelisation patented technology guarantees the accuracy and surface finish of molded products.
3. fused deposition modeling (FDM)
FDM process is also called extrusion molding. The key is to keep the semi fluid forming material just above the melting point (usually controlled at about 1 0C higher than the melting point). FDM head by CAD hierarchical data control makes the fuse material semi fluidity (wire diameter as above 1.5mm) squeezed out from tut head, thin solidified shape, a laminated layer and finally formed the entire model. The BFB series and Rapman series products of American 3DSYSTEMS company all adopt the FDM technology, its craft characteristic is directly uses the engineering material, ABS, PC and so on material to make, suits the design different stages. The disadvantage is poor surface finish.
4. Selected Laser Sintering(SLS)
The C02 laser is used as energy source, and the materials used at present are mostly powder and materials. A thin (100 mu -200) powder is uniformly laid on the worktable, and the laser beam is selectively sintered according to the layered profile of the parts under computer control. After the first layer is finished, the next layer is sintered. After all the sintering is finished, the excess powder is removed, and the parts are obtained after grinding and drying. At present, the process materials are nylon powder and plastic powder, and metal powder is used for sintering. Germany's EOS company P series plastic forming machine and M series metal forming machine products, is the world's best SLS technology equipment.
SLS technology can fall into the category of Rapid Prototyping and can also be classified as Rapid Manufacturing because SLS technology can be used as a direct Rapid Manufacturing final product.
5.Direct Metal Deposition (DED)
Equivalent to multi-layer laser cladding, the use of laser or other energy in the material from the nozzle when the output of synchronous melting material, solidification after the formation of solid layer, layer by layer overlay, and eventually form three-dimensional solid parts. DED has low forming accuracy, but the molding space is unlimited, so it is often used in the manufacture of large metal parts.
6.Layered Object Manufacturing (LOM)
Basic principle: use laser and other tools to cut and accumulate sheet materials, and finally form three-dimensional solid. Wood like parts, plastic parts and metal parts can be made out of cardboard, plastic board and metal plate respectively. The bonding between the layers of cardboard or plastic plates is often achieved by the use of adhesives, and all layers of metal plates are directly combined with conventional welds such as thermal brazing, fusion welding, or ultrasonic welding and bolted connections. The biggest drawback: can not do too complex parts, materials range is very narrow, each layer thickness can not be adjusted, the accuracy is limited.
Part 3: Several Mainstream Rapid Manufacturing Processes Advantages and Disadvantages
1. Selected Laser Sintering(SLS)
The use of SLS devices can be shaped hot runner system for direct manufacturing of metal mold and injection mold, its hardness is higher Rockwell hardness, the performance reaches the forging level, can also make specific and complex functional parts directly. It is because of SLS technology for small batch special and complex functional parts of Rapid Manufacturing, and a plurality of parts forming a one-time manufacturing, multi varieties, small batch of personalized Rapid Manufacturing, which has been recognized and widely used in aerospace, military, automotive engine testing and development medical field.
2. Vacuum Infusion Molding Rapid Tool (VCM, SeLected Laser Sintering)
Also called the "vacuum injection mold", using the original model, to produce silicone mold in a vacuum, and casting with the PU material under vacuum condition, and cloned the same copy of the original model, is one of the most commonly used rapid tooling technology. By this technology, can produce similar engineering plastics to meet a variety of functional characteristics of the product, also can undertake small batch, production.
A general set of VCM silicone mold can replicate 20 sets of products, especially suitable for small and medium-sized, fine parts of replication, such as instrumentation, auto parts manufacturing industry. The processing technique can satisfy the application in the trial production process of the product, and has the advantages of short time, low cost and fast speed.
Usually the process is: 3DP/SLARapid Prototyping (hand plate, prototyping)-----VCM vacuum injection molding machine (rapid mold manufacturing) --- small batch replication production.
3. Reaction Injection Moulding(RIM)
Also known as the "low pressure" is a new technology applied in the production of rapid molding, it will be a two-component polyurethane material by mixing, under normal temperature and low pressure environment into the fast mold products are formed through the material polymerization, crosslinking, curing and other chemical and physical processes. Because the raw material is liquid, with less pressure to quickly fill the die cavity, thus reducing the clamping force and mould cost, especially suitable for production of large size, a large area of the parts, such as car bumper, dashboard, tail etc.. A RIM mold can replicate 200 products, and has been used in automotive research and development, trial production, instrumentation, sculpture, architecture design, and other fields.
The general process is: SLS/CNCRapid Prototyping (hand plate, prototyping), ------RIM rapid mold manufacturing - injection molding (small batch replication, production)
4. Computer Numerical Control(CNC)
CNC is a program controlled automatic machine tool. The control system is capable of processing logic control rules encoding or other symbolic instruction through the computer program, the decoding, so that the implementation of the provisions of the machine movement, by cutting the wool blanks into semi-finished parts. Since 1952, Massachusetts Institute of Technology developed the world's first CNC machine tools, CNC machine tools in manufacturing industry, especially is widely used in automotive, aerospace, and military industry, digital technology both in hardware and software, are rapidly developing.
CNC compared to the traditional machine tool, it has the characteristics of digitization, high efficiency, batch production, in addition to the structure of complex shape, basic can cope with, so it is not strictly Rapid Prototyping technology, but the industry generally or to put it in the category of Rapid Manufacturing.
Part 4: why should the world vigorously promote the development of Rapid Prototyping and Rapid Manufacturing technologies?
Obama at the end of 2011 and April 2012, two times in the public speaking advocate Rapid Prototyping and Rapid Manufacturing technology, the artificial intelligence, 3D printing, robots as three pillars to revive the U.S. manufacturing sector, that they can use the technology, the manufacturing industry "return to the United states". Subsequently, the 3D printing industry in the United States was supported by the government. 5 government departments in the United States Department of defense, the Department of energy and the Ministry of Commerce will jointly invest $45 million, United Group consists of Ohio and Pennsylvania and West Virginia enterprises, schools and non-profit organizations will invest $40 million in the state of Ohio, established a research innovation in manufacturing by government departments and private departments jointly funded the national increase in material manufacturing Innovation Institute (National Additive Manufacturing Innovation Institute), the development of 3D printing technology.
The United States and Europe scholars recently predicted that based on the Internet and new materials, new energy with the combination of the third industrial revolution on the basis of the forthcoming, it takes "Digital Manufacturing" as the core, will make the factor allocation of global technology and market factors of revolutionary changes. Some experts believe that countries such as virtue have achieved pilot technological breakthroughs, which may occupy the commanding heights of the revolution and re divide the global division of labor. To be sure, the new scientific and technological revolution will rely on the modernization process and the strong demand of international competition, and will also be more closely integrated with new industries, and promote each other.
The U.S. "time" magazine has 3D printing industry as "the ten fastest growing industry", the British "economist" magazine believes that it will work with other digital production pattern to promote the realization of the new industrial revolution.
So much attention to 3D printing, the reason for this nothing more than the following points:
1. changes in consumption patterns have led to changes in the patterns of industrial manufacturing
The original human consumption mode is affected by industrial manufacturing methods, what sold on the market, the human consumption of what he wants, no; the first and second industrial revolution, mankind from the earliest hand, self-sufficient production and consumption pattern to jump sharply, rich product circulation of globalization stage, now is oversupply, people's consumption can in turn affect the manufacturing; and now people begin to reject mass, no personality made things more personalized products, such products often have a personalized, customized, diversified, traditional, time-consuming long mold manufacturing mode is unable to adapt to the new trend of consumption, then, Rapid Prototyping and Rapid Manufacturing technology came into being. Compared to the mold production of mass production manufacturing, 3D printing can produce personalized products under certain constraints, can be called "mass customization manufacturing mode", is based on the Internet to support intelligent mass customization mode, or "decentralized production, on-site sales", marks the era of personalized consumption the arrival of.
Once consumers are choosing and purchase has good production goods in the store, now you can according to their needs, in the "3D printing shop" customized production experience, timely access to their products of love.
2. Rapid Prototyping and Rapid Manufacturing have obvious advantages over traditional die Manufacturing
Rapid Prototyping is not affected by the product structure and shape of the restrictions, any complex shape and structure, as long as CAD data, can be easily done, so as to provide the possibility of personalized and customized; and the use of Rapid Prototyping technology and Rapid Manufacturing technology, is not required to open mold, realizes dieless manufacturing the development of new products, the decline in the cost of the traditional way of 1/3-1/5, shorten the period of 1/5-1/10. Coupled with Rapid, Prototyping and Rapid Manufacturing equipment, most can realize unattended, 24 hours uninterrupted processing, but also for the manufacturers to save labor costs, improve production efficiency.
Rapid Prototyping and Rapid Manufacturing technology can be used in product design, development, manufacture, small batch production, and whether it is industrial manufacturing field, the field of education, medical field, cultural relics protection areas or other areas to a plane, to a small ring, as long as the need for physical proof or trial, all you can use the Rapid Prototyping and Rapid Manufacturing technology, is very wide.
The late Rapid Prototyping and Rapid auxiliary processing capacity of Manufacturing is greatly reduced, to avoid the outsourcing of data leaks and time span, especially for some high security industries, such as military, nuclear power field.
3D printing technology, "print" products are naturally seamless, integrated molding, the stability between the structure and connection strength is much higher than traditional methods.
3.The future manufacturing industry must be low-carbon
The real rise of the Third Industrial Revolution concept and the spread of globalization are closely related to the pressure of global sustainable development. Specifically, first, by 1980s, the depletion of oil and other fossil fuels, and the consequent global climate change, have created a crisis for the continued survival of mankind. Two, the original industrial economy model driven by fossil fuels can no longer support the sustainable development of the whole world. Therefore, we need to seek a new model that will enable mankind to enter the "post carbon" era. Rapid Prototyping and Rapid Manufacturing living, with a new attitude of green, energy saving, low carbon, environmental protection has been the global governments and institutions recognized and trusted.
Rapid Prototyping and Rapid Manufacturing using the additive manufacturing technology, subtraction and milling type differences with the traditional manufacturing mode, basically is the production of how much weight, the cost is the same weight of materials, so the cost of materials decreased significantly; customization will not produce product inventory, in the premise of to reduce carbon emissions and raw material consumption, higher production efficiency. 3D printing of raw materials using only traditional production methods of 1/10, which in today's era of precious resources, no doubt has a huge advantage.
4.The future competition of the global manufacturing industry lies in high value-added design
In the global economy today is moving towards the third industrial revolution and economic weakness in the background, European countries began to make "re industrialization" strategy -- from low value-added manufacturing sectors, to reconstruct the manufacturing industry chain, focus on strengthening the re creation of high value-added sectors, through technological innovation, design innovation, change the mode the traditional manufacturing industry, reduce labor costs, improve the international competitiveness, and provide a lot of jobs. The maturing of Rapid, Prototyping and Rapid Manufacturing provides solid conditions for this strategy.
Manufacturing is the original production and processing restrict the development of new products R & D design links, you need to take into account the final can be produced from the beginning; and Rapid Prototyping and Rapid Manufacturing technology for product design is not restricted, as long as the design, CAD modeling, any structure and shape can be produced so, in terms of industrial design and creative energy will be infinite release, who have the ability to highlight the industrial design, who will become the future leader of the global manufacturing industry to create high profits.
Compared to the 2D print or even every year tens of billions of billions of dollars in the market, 3D print the current annual market space of only hundreds of millions to billions of dollars, or a place in the market. But in February 2011 the Economist (The Economist) magazine said "3D printing technology can be an inexpensive molding from a single product to tens of thousands of products, and further damage to economies of scale, as the 3D printing company did...... Just as the printing of 1450, the steam engine of 1750 and the transistor of 1950, no one was able to correctly predict their future prospects, and no one could predict the long-term impact of 3D printing technology. 3D printing has arrived, and it could destroy every field it touches in the future."