Printers, the most commonly used computer devices that are so far meant to produce the actual representation of the graphics upon the monitor screens connected to a computer system on paper. With time, we got Dot-Matrix, Daisy Wheel Printers to modern-day 3D Printers, Thermal Printer, Toner-based Printers, etc. In the beginning, we only witnessed 2D printing, but today we are buzzing out various 3D Printed objects as well as non-human readable barcodes (2D Printing tech).
3D printing: An overview
3D printing or additive manufacturing is a process by which three-dimensional solid objects are created with the help of digital files. The creation of a 3D printed object is achieved by an additive process of successive layers each after another on it.
Each of the added layers can be seen as a thinly sliced cross-section of the object. 3D printing is the opposite of subtractive manufacturing which excludes the cutting out or shaping out as well as hollowing the required materials like metal or plastic.
History of 3D printing
The pioneers in 3D printing are regarded to Japanese investor Hideo Kodama in 1981 by the additive process. He was successful in creating a solid object that uses ultraviolet lights to harden polymers. This is a stepping stone to stereolithography (SLA).
Stereolithography was invented by Charles Hull, a process very similar to the technology used in 3D printing to create smaller versions of objects so that they can be tested before investing time and money on them. Thus, Charles Hull is regarded as the founder of 3D printing of the modern era.
How does it work?
3D printing is one of the most revolutionary technologies of the 21st century, what you might not realize is that there are tons of different 3D techniques out there. 3D printing is an additive process where each after layer of print is continued till the real shape of the object emerges.
a 3D object is created by layering where the printer will add one layer of an object at a time until you have a fully formed structure. The most material used in 3D printing is plastic. But the use of some other materials allows for the creation of some pretty amazing products beyond simple tools and toys. 3D printing food is becoming very popular and additive manufacturing has allowed for the creation of some pretty intricate treats.
Types of 3D Printing
There are mainly seven major types of 3D Printing as mentioned below:-
It is the world’s first 3D printing innovation introduced by Chuck Hull in 1986. It works on a 3D printing technique called Vat Polymerization where a material called photopolymer gum is generally restored by a light source. Stereolithography (SLA) is the first modern 3D printing technique. SLA printers are experts in giving elevated levels of details, smooth surface, tight resistance, and the required completion, which are well matched.
Selective Laser Sintering
SLS softens together nylon-based powders into strong plastic. Just because SLS parts are produced using the genuine thermoplastic material, they are tough, reasonable for utilitarian testing, and can uphold living pivots and snap-fits with ease. It is rapid prototyping technology that turns 3D CAD data into physical parts in a matter of hours.
SLS is an additive manufacturing technology that uses powdered Nylon 11, Nylon 12, and peek material. Parts produced are lightweight, highly durable, and both heat and chemical-resistant, making. SLS is an excellent choice for producing production parts without the expense of tooling.
Fused Deposition Modeling (FDM)
A Fused Deposition Modelling or FDM printer works by expelling a plastic fiber layer-by-layer onto the forming stage. It is a layer additive manufacturing process that uses production-grade thermoplastic material to produce both prototype and end-use parts. This technology is known to accurately feature details and has an excellent strength-to-weight ratio.
This type of printer utilized a resin tank or fat to hold resin while a build platform lowers down to extract the part out of the resin tank. The build platform is attached to a ball screw that raises and lowers the build platform in and out of the tank while a peeling mechanism separates each layer from the bottom of the VAT. For most printers of this type, the VAT is consumable due to the special non-stick coating on the bottom of the bat that only allows the part to be peeled off after each curing step.
Multi Jet Fusion is a 3D printing process, so it’s layer by layer and it’s using nylon powder as its base. It’s very similar to selective laser sintering with a major difference in that, instead of using a laser it’s using ink agent to promote the sintering and so, it’s got a carriage that passes back and forth over the entire part bed and it’s got a bunch of ink heads on it and it’s dispersing both a fusing agent, which promotes energy absorption and the sintering of the parts as well as what they call detailing agents at the bounding edge.
PolyJetDirect Metal Laser Sintering (DMLS)
Direct Metal Laser Sintering is also known as DMLs is an additive manufacturing technology that creates metal parts directly 3D CAD data without the need for tooling. DMLs utilize a variety of metal and alloy materials such as stainless steel, cobalt chrome to create strong and durable parts and prototypes.
DMLs are an excellent choice for functional metal prototypes, high-temperature applications, and end-use. The DMLs process begins in the same person as other Leah additive manufacturing technologies. A program takes 3D CAD data and mathematically slices it into the 2D cross-sections, each of the sections will act as a blueprint telling the DMLs machine exactly where to center the metal material. The data is then transferred to the DMLs equipment. And then it is processed to the recorder assembly that supplies powder to create a uniform layer over the base plane.
Electron Beam Melting (EBM)
Electron beam additive manufacturing or electron beam melting is a type of additive manufacturing that is used for 3D printing for metals like stainless steel and cobalt. The raw material i.e powder of metal is placed under a vacuum and fused from heating by an electron beam.
Principles in 3D Printing govern the technique of completion of printing from modeling to the end-user product.
4-dimensional printing (4D) also known as 4D bioprinting, active origami, or shape morphing system uses the same technique like 3D printing which is computer program deposition material like 3D. It is also an additive manufacturing technology. 4D is just one step ahead of 3D printing, it includes the transformation over time itself. Therefore it is a programmable matter which after the fabrication process the printed object reacts with the parameter and surroundings of the environment such as temperature, humidity, etc.
3D printings are based on mathematical coordination which represents the surface of 3D material in the 3D space via specialized software. In 3D printing, 3D models represent a physical body using a collection of points in 3D space. The required model can be easily prepared by connecting various geometrical entries such as line, curve line, curve surface, triangle, polygon, etc. 3D can be made even manually by user preferences.
Before printing a 3D model from an STL file, firstly it is examined for errors. Almost every CAD application produces some kind of error in STL files, of the following type:-
- Faces normal
- Noise shell
- Manifold Error
There is a step for fixing the error in the STL file called “repair” and it will fix it automatically itself. A good 3D printing requires an error-free STL file that will print the 3D model according to the instructions placed in software and point-to-point acquisition/mapping.
Normally, 3D focused on polymers for printing due to the ease of manufacturing and handling polymeric materials. However, now we have achieved the technology that now we can print various models using polymers and metals, and ceramics.
The use of polymers was restricted in the betterment and designer structure of the 3D model. But since the technology able to use materials like metals and ceramics have vast-en the design and the different structure of 3D models.
Multi-Material 3D Printing
Multi-material 3D printing is an additive manufacturing process that prints the 3D oriented objects layer by layer by the use of different materials at the same time. Suppose you are wishing to print a multicolor object. We have to set such programs in 3D printing software to obtain the required models.
Since 3D is an additive process that is printed layer by layer, there is not so much to understand about the mechanism of multi-material 3D printing. We can very easily change the layer-to-layer materials setting.
3D Printing Processes
The section describes various ways or processes for 3D Printing at a mass scale.
Vat polymerization is a method in 3D printing to print three-dimensional objects using Photopolymerisation, in which liquid polymers are exposed to open ultraviolet (UV) light which turns the liquid polymers into a solid object. Digital light processing technology is used for this process.
Firstly, 3D designs are created in the 3D printing software. Then the digital light process uses the light to project an image onto the liquid polymers, and after projections, the protected area becomes a solid object.
Material jetting is the process of 3D Printing in which the material is jetted onto a build platform layer by layer continuously or Drop on Demand (DOD). The method of material jetting in 3D printing is similar to 2D jet printing. Material is jetted on the build surface by a nozzle that moves across the build surface horizontally to shape the required model. The material layer is then cured and hardened using ultraviolet (UV) rays. As material must be deposited in drop, the amount of material is limited. Mostly polymers or wax is used for jetting due to their vicious nature and the ability to form a drop.
Binder jetting is the process of 3D printing in which two materials; a powder and a binder are used to print a 3D model. The build material is in powder form and the binder which acts as an adhesive is in liquid form. A print head moves horizontally along the X and Y axes of the machine and deposits material build material and binder material alternately each after another. After each layer, the object being printed is lowered on its build platform.
Since binder jetting is completely dependent upon binding, the build material characteristics are not always suitable for the printing processes. Only a few materials hold the property of binding. The binding processes are even much slower than materials jetting.
Powder Bed Fusion (PBF)
The Powder Based Fusion (PBF) commonly used Direct metal laser sintering (DMLS), Electron beam melting (EBM), Selective heat sintering (SHS), Selective laser melting (SLM), and Selective laser sintering (SLS).
Powder bed fusion (PBF) is a method of 3D printing that uses either a laser or electron beam to melt and fuse material powder. EBM method requires vacuum but the PBF method simply spreads the powder material layer after layer. The process sinters the powder, layer by layer.
In PBF a thin layer of material is spread over the build platform then the laser fuses the first layer. Again the powder is spread and it is fused. The process repeats until the entire model is created.
The sheet Lamination process includes ultrasonic additive manufacturing and laminated object manufacturing. The ultrasonic additive manufacturing process uses sheets of ribbon of metal, which are bound together using ultrasonic welding. Laminated object manufacturing uses the same approach layer by layer paper as build material and adhesive instead of welding.
The material is positioned in place on the cutting bed. Then the material is bonded in place, over the previous layer, using adhesive and the required shape is cut off from the layer using a knife or laser, and so on the process continues. But now mostly lasers are used for this purpose.
Direct Energy Deposition (DED)
Direct Energy Depositions (DED) is a 3D printing method that uses a focused energy source, like plasma arc, Laser, or electron beam, to melt a continuously deposited material by a nozzle. DED is of great importance, it has a different role in 3D printing. It can be used to add material to an existing substance. On many occasions, it is used for repairing or building new parts with ease.
Usually, it is used to work on metal parts, but it can be also used with polymers and ceramics. Almost every weldable metal like aluminum, Inconel, niobium, stainless steel, titanium, etc. can be additively manufactured using DED.
Unlike the name 3D Printing suggesting, the application of this technology is not confined or bounded within the printing industry but 3D printing had successfully gained its reach in the field of biology by 3d printing various body organisms. Some of them are discussed below:-
This is the most accurate application for 3D Printing which is ready to bless civil engineering in the coming future. This uses 3D printing as the main source for building concrete structures, powder bonding, and various additive products used during any construction that includes buildings, bridges, etc finding its scope in various public, private and industrial sectors with time. The first concrete or block was successfully 3D printed in the early 1990s but it took around three decades to print a house completely with the 3D printer in 2017 in Russia.
3D Printing in Construction is expected to deliver a more efficient way to construction with less labor costing and highly quick and efficient workflow across the sector.
One of the most trending buzzes around 3D Printing aka Bioprinting is printing organs and tissues that can be easily implanted in place of a failed body part known as Prosthetics. Apart from Prosthetic. Pills can also be produced by Binder Jetting Process that enables high porous structure allowing intake larger dosage at a single take can easily and quickly be digested and ensures better treatment of various diseases like epilepsy.
Earlier it was difficult to implant failed body parts due to their high market value but 3D printing has today enabled the easy replacement of the body part without any compatibility issues. With 3D Printing, Scientists can now print the exact needed part identical in dimensions by taking measurements and directly modeling it into a printer.
Various institutions across the planet are adopting 3D Printers to minimize the gap between graphics in the pages of books the three-dimensional modeled structures. In return, this enables students to be more interested and productive towards the topic as well as reduces the cost of buying items physically (for lab work).
On the one hand, Engineering students can easily model complex structural prototypes without wasting ample time in working for a real one, and on the other hand, Medical students can practice various ways of organ implantation without working on a real body without practice. Apart from the above streams, Students aiming to explore fossils or ancient preserves can easily access them by modeling into 3D Printing minimizing the risk of accidental damages.
While the World is shifting towards sustainable growth, Scientists or Researchers can three-dimensionally print various items through a designed CAD image via 3D Printers. In short, it is a method to artificially manufacture foods through layer by layer additive process. Some modern-day printers are often pre-loaded with various designs, might be Cakes, Meats, etc and they provide complete controls over the colors, designs, and material of the printed foods.
The technique was first introduced in the year 2005 by a group of students at Cornell University that later took the edge and the first vegan food was printed recently in the year 2018. Since the first introduction, ingredients like cheese, mashed potatoes, chocolate powders (essentially for cakes), and sauces (for pizzas, etc) are commonly used as the main sources for three-dimensional food printing.
So this was it for 3D Printing. We will catch you up in the coming one. Hope you liked our presentation, but if not, kindly leave a comment below with valuable feedback.