The development history of 3D printing is long, dating back to 1981 when this new concept emerged. However, the products produced were quite expensive, and people began to explore this method of manufacturing. But thirty years later, today, 3D printing has truly entered its golden age. Now, breakthroughs have been made in the precision, speed, and material applications of 3D printing.
1. Multi-field Applications of 3D Printing
The applications of 3D printing are becoming increasingly widespread, covering education, culture, healthcare, machinery, electronics, aerospace, military, and more.
2. Similarities and Differences Between Traditional Manufacturing and 3D Printing
For example, consider a hollow-designed sphere with dozens of flowers on its surface. Using traditional machining is quite troublesome, as each pattern must be modified individually. In contrast, using 3D printing avoids material waste, which is why it is also called additive manufacturing, meaning that materials are gradually added to create solid parts. The traditional method involves creating a blank and then removing excess material to leave the desired shape. If a problem is detected, new molds must be created for modifications; however, 3D printing builds up material bit by bit, allowing you to quickly see the finished product.
3. Technical Implementation of 3D Printing
3D printing technology is applied to industrial production. What is actually needed for 3D printing is not a physical object, but a digital model. If you want to print a physical object using 3D printing, you must create a model on a computer or use a 3D scanner to digitize the object, creating a 3D model, which can be printed in as little as fifteen minutes. Currently, 3D printing technology is divided into FDM, DLP/SLA, and SLS.
FDM (Fused Deposition Modeling)
Compared to DLP and SLS technologies, FDM is relatively simple, making it more accessible to a wider audience and easier to integrate into homes. It uses thermoplastic materials that are extruded into a semi-molten state, building prototypes directly from 3D CAD data by stacking layers. The advantages of FDM technology include a simple mechanical structure, easy design, low manufacturing, maintenance, and material costs, and it is environmentally friendly. Therefore, FDM is the most commonly used technology in home desktop 3D printers. It is a relatively traditional printing method that does not use lasers, is cost-effective, but has lower precision and very slow printing speeds. This is the method most people encounter, typically used in the educational market.
SLS (Selective Laser Sintering)
SLS uses relatively high-tech powders that melt under high temperatures from laser exposure. A thin layer of powder is spread on the workbench, and the laser scans the cross-section of that layer, raising the temperature to the melting point, thus achieving sintering and bonding. This process is repeated, layering powder, sintering, and then grinding and drying until the model is formed. Essentially, 3D printing is like repeated 2D printing; if you slice an object very thinly, you will find that each slice is a shape, and when all shapes are combined, a three-dimensional object is created. Thus, we use lasers to draw the shapes. SLS parts have environmental resistance (to temperature, humidity, and chemical corrosion) similar to thermoplastic materials; however, SLA parts have poorer resistance, for example, SLA parts made from epoxy resin are easily corroded by moisture and chemicals and can soften and warp in environments above 38°C.
SLA (Stereolithography)
SLA is a light-curing technology that is relatively advanced in China. “Stereolithography” involves a laser beam tracing the first layer shape of an object on the surface of liquid resin, then the platform descends a certain distance (between 0.05-0.025mm), and the cured layer is submerged in liquid resin, repeating this process. The resin used is photosensitive resin, which solidifies upon laser exposure, allowing for fast model formation with high precision.
DLP (Digital Light Processing)
DLP, known as laser forming technology, shares many similarities with SLA 3D printing technology. If we compare production to drawing a circle with a pencil, SLA technology is like drawing layer by layer, while DLP is akin to directly stamping. Two important aspects of mass production are efficiency and material costs. There is a type of 3D printer that can achieve printing speeds up to one hundred times faster than traditional manufacturing, known as continuous surface technology, which has been developed by a company in Shenzhen called Light Prism Technology. Printing a hollow sphere using traditional FDM 3D printing takes 2-5 hours, with the fastest being at least one hour, while using the latest continuous surface technology only takes about ten minutes, which is astonishing. Once this 3D printer hits the market, it will significantly impact traditional processes.
4. The Impact of 3D Printing on Manufacturing and Traditional Processes
3D printing can unleash endless imagination, turning many previously virtual concepts into reality, including the following:
(1) Customization
For example, in dentistry, everyone’s teeth are different, but 3D printing can resolve the conflict between customized production and mass production, allowing for the mass production of customized implants, dental crowns, and more.
(2) Real-time
Due to the fast speed of 3D printing, a designer can create a product version in the morning, show the finished product to the leadership by noon, design another version by 6 PM, and see the finished product again the next morning, greatly accelerating the speed of new product development. If not particularly complex, 3D printing can produce a finished product in 3 hours, while traditional prototyping takes 4-6 weeks each time, thus enhancing the overall speed of industrial design.
(3) Pollution-free
Since the raw materials used in production are environmentally friendly, the entire production process is pollution-free. There is no waste gas or wastewater pollution, nor any scrap material waste.
(4) Digitalization
Once digital dentistry matures, the technical requirements for doctors will be greatly reduced. Patients only need to scan their teeth for two minutes in the hospital to understand all the issues and solutions.
Additionally, 3D printing can be used for orthodontics, printing personalized clear aligners. During orthodontics, the direction of tooth movement can be to the left or forward, and by how many millimeters? Previously, dental surgeries relied solely on the personal experience of the doctor, but digital dentistry increases the stability of surgeries and lowers the technical threshold for doctors.
(5) Speed
Compared to traditional industrial processes, 3D printing does not require manpower, transportation, or other preliminary preparations; it only needs machines and raw materials to quickly enter production.
(6) Automation
It can be said that the only thing separating virtual imagination from reality is a 3D printer. The one-click production of 3D printing saves a lot of labor costs and human errors.
Whether 3D printing disrupts the manufacturing industry or replaces traditional processes, it has a significant impact on us and makes more people feel meaningful. We look forward to 3D printing becoming better and better in the future.