4D Printing (4DP): Technology of the future

Additive Manufacturing or 3D Printing has evolved into a viable, trusted & tangible, technological alternative to a host of traditional manufacturing & fabrication methods. However, lurking in the shadows of this technology, a new development is slowly & steadily acquiring shape & potential to disrupt major industries in a far more radical way than 3D Printing has done so far. Adding the ‘fourth’ dimension of ‘Time’ to the usual three dimensions of length, breadth & height, in an additive manufacturing process has resulted in the discovery of ‘4D Printing’.

The question of ‘what is 4D Printing?’ can hence be answered as follows: Printing, manufacturing or fabricating objects, tools, parts, in a way that allows them to alter shape, size, form & structure, due to external influences in form of energy, like light, temperature or other environmental stimuli, is known as 4D Printing. Majority of research in 4DP is dedicated to combining ‘technology & design’, aimed at inventing self-assembling & programmable material technologies, which have the potential to revolutionize Construction, Manufacturing, product performance & assembly.

Differentiating between 3DP (3D Printing) & 4DP is hence simple. 3DP works by printing layer upon layer of material of a 2D structure, in a path from the bottom to the top, generating a 3D volume or object. 4DP repeats the same process, however, the difference is the materials used to print these objects. 4DP requires advanced & specially programmed materials that change shape & structure, in response to any changes in their environments.  

One example of these advanced & programmable materials is a Shape Memory Polymer (SMP). SMPs have the ability of large-scale elastic deformation, in response to environmental stimuli. Figure 1 shows us an example of this phenomenon. When a certain change in temperature is induced, the 4D printed inanimate flower object; made of SMP material, changes shape in response to rising temperatures. As is evident in Figure 1, different levels of temperature changes, induce different deformations of the structure.

Different smart printing materials can be used to deliver desired changes in model structures. SMPs as shown in Figure 1, work on the mechanism of the Shape Memory Effect (SME). They fall under the category of Thermo Responsive Materials: materials that change size, shape when thermal energy is applied as a stimulus. Various such materials are currently being developed, namely Shape Memory Alloys (SMA), Shape Memory Hybrids (SMH), Shape Memory Ceramics (SMC), and Shape Memory Gels (SMG). SMPs are currently the preferred materials for 4DP, as they are currently far easier to develop & print with.  

3D Printing & Auto Industry

Automobile industry has been an early industrial adopter of 3D printing. Over the span of a

decade, the Automobile industry has witnessed 3D printing technology transform from a

useful alternative to an indispensable tool. Initially, focused on making prototypes, 3D

printing now is responsible for creating complex parts, speeding up tooling cycles,

enhancing measurement & testing, while also providing customized solutions.

Miniature 3D printed designs of cars are easy to test. With advances in 3D printing &

compatible materials, designers can test various forms & practical functions. This helps in

finalizing optimum design ideas faster, as life size designs of parts & models can be printed

immediately upon approval.

Rapid tooling is growing at an enormous pace within the industry. 3D printing is responsible

for shrinking the tooling process & making it easier to develop task specific tools. Designing

custom tools & 3D printing them saves time, material cost & machine time, making it

profitable for automakers in every way.

Customization for select vehicle models can be an expensive affair for automakers. From the

interior of a car to the essential functional parts, customizing & mass-producing custom

parts in low volume proves costly. Using 3D printing, customized parts can be easily

produced, while lowering cost of customization to OEMs & the end user alike. This is

especially true for EMVs, which require lightweight & specially designed parts to be

produced in low quantity.

Measuring & validating accuracy of parts & fixtures, on demand, is now possible thanks to

3D printing. Using FDM technology, designers can print special tools that last longer & are

lighter as well as mobile. This makes it easy to carry them to any point in the assembly line.

Using rubber like materials also helps avoid scratches & other type of damage on end parts,

making measurement & validation cheaper, faster & more efficient.

Using FDM, SLS or SLM technologies for 3D printing, automakers can test various iterations

of a model rapidly. This also extends to the ability of being able to use multiple materials in

making one model & testing the outcome right away. This helps validate complex part

designs & make designers aware of parts that may not be functional in the real world as

well.

With 3D printing making it easier to design new models, make complex parts with ease, the

automobile industry is on its way to a complete revolution. Shorter lead times in design,

fabrication, testing & validation are helping the industry cater to the varied consumer &

environment needs with ease.

3D Printing & Rockets

3D printing is revolutionizing the Aerospace & Aviation industry. As we outlined in our blog on the topic of “3D Printing in Space” (https://3ideatechnology.blogspot.com/2021/04/3d-printin-in-space.html), 3D printing is crucial to driving down the cost per kilogram of putting payloads in space. One of the most important ways 3D printing achieves this, is by making the process of manufacturing ‘rockets’, faster, cheaper & efficient. 

Modern era requirements of space travel, scientific research, military reconnaissance & broad coverage offerings by mobile & broadband networks to name a few, require space launches of humans &/or satellites into space. This is where launch vehicles or rockets, as they are most commonly known, come into the picture. Launching any payload into space with a rocket, however, is an expensive & risky affair. On average a rocket used to put payloads into space has more than 100,000 parts, drastically raising the probability of errors & mistakes, which may lead to a mishap. To add to this risk, rockets require huge amounts of fuel &have a comparatively low payload carrying capacity in terms of weight. Hence, the heavier the payload, higher the cost of launching it into space. This is where 3D printing changes things. 

Traditional rockets designs like the Titan rockets, which powered the Apollo missions to the Moon, have more than a 100,000 parts. These need to be fastened together with nuts & bolts, specials glues, which have to withstand enormous pressure during launch. 3D printing can help manufacture rockets & rocket parts, ‘whole’, using novel methods of Direct Metal Laser Sintering (DMLS) or Selective Laser Melting (SLM). This leads to an almost 100x reduction in the number of parts & components. This not only makes the rockets stronger in terms of withstanding external pressures, but also lighter. 

Using 3D printing to manufacture rockets, drastically reduces lead times. Designing 3Dmodels in proprietary virtual modelling software & printing these models takes a short time of only 60 days, in some cases. This is a 10x reduction compared to traditional methods, where it would take more than two years to manufacture a new rocket that is ready for space launch. 

In addition to making the process of manufacturing rockets faster, 3D printing also helps in making them efficient. Fuel tanks & engines make up for the heaviest parts of a rocket. By designing fuel tanks in one piece using novel metal alloys (carbon fiber, titanium aluminide, graphene), 3D printing can help make fuel tanks leak proof & lighter. Engines also benefit greatly due to unique & efficient thruster & combustion chamber designs. Rockets manufactured using 3D printing have been proven to provide almost 98% more thrust, at a fraction of the cost of traditional methods of making them. This means more lighter, powerful & efficient rocket engines & more space for carrying items in the payload to be delivered. 

As the Human race slowly approaches the dream of inter-space & inter-planetary travel, rockets & their indispensable utility in space launches remain paramount to realizing this dream. Luckily, for all of us who dream of travelling to the stars, 3D printing is here to expedite this voyage into the star-studded highways of space, by making rockets faster, cheaper & more efficient than ever before. 

3D Printing & Batteries

Batteries have become indispensable tools in the battle against fossil fuels & the rise of the EMVs (Electric Motor Vehicles) has highlighted the curial role they play in this struggle. The revolution in energy storage has also brought us Electric Boats & Airplanes in addition to EMVs. As usual 3D printing is playing a pivotal role in making batteries cheaper, efficient & compatible with a wide array of applications across the Automobile, Aviation & Marine industry. 

3D printing is known to provide a capacity for rapid prototyping & the ability to achieve economies of scale at a blazing speed. Batteries produce energy in different cells that are put together inside them. Traditional methods of manufacturing require these to be produced separately & put together to form a single battery unit. With 3D printing methods, custom batteries with suited shapes of cells can be printed ‘whole’, eliminating extra time & improving the speed at which large amounts of batteries can be produced. This greatly reduces the cost of manufacturing batteries. 

In addition to reducing the price of manufacturing for batteries, 3D printing, also helps in raising the efficiency of batteries, in terms of the amount energy being stored. Porous electrodes in a battery help raise energy density. 3Dprinting can produce such electrodes that are porous at a ‘nano’ level, using a three dimensional ‘lattice’ structure. This lattice structure helps in exposing more surface area of the electrodes, where the chemical reactions that make a battery work are achieved. Hence the battery produces more energy. 

3D printing also aids in fabricating batteries of various shapes & sizes. As a battery can be 3D printed ‘whole’, battery makers do not have to glue together different cells that make up a battery. 3D printed batteries hence can be fashioned into desirable shapes & are lighter than their traditional counterparts. This helps product designers in the EMV, Aviation & Marine industries design vehicles, planes & boats, respectively, with a higher level of freedom & concern for accommodating cumbersome battery shapes. 

With 3D printing disrupting & revolutionizing manufacturing methods of batteries, a cleaner future, free of fossil fuels has dawned & the time when mankind achieves net zero emissions is on the horizon.