Materials for Industry 4.0

What is industry 4.0?

We’re in the midst of a significant transformation regarding the way we produce products thanks to the digitization of manufacturing. This transition is so compelling that it is being called Industry 4.0 to represent the fourth revolution that has occurred in manufacturing. From the first industrial revolution (mechanization through water and steam power) to the mass production and assembly lines using electricity in the second, the fourth industrial the revolution will take what was started in the third with the adoption of computers and automation and enhance it with smart and autonomous systems fuelled by data and machine learning.

 

Emerging technology sectors under Industry 4.0

• Additive Manufacturing & Advanced Materials - Additive Manufacturing is the construction of complex three-dimensional parts from 3D digital model data by depositing successive layers of material. Advanced Materials focuses on new materials and modifications to existing materials to obtain superior performance in one or more characteristics that are critical for the application under consideration. They can also exhibit completely novel properties.
• Artificial Intelligence - The simulation of human intelligence processes by machines, especially computer systems. These processes include learning (the acquisition of information and rules for using the information), reasoning (using rules to reach approximate or definite conclusions) and self-correction.
• Big Data - Extremely large data sets that may be analysed computationally to reveal patterns, trends, and associations.
• Cloud Computing - Shared pools of configurable computer system resources and higher-level services that can be rapidly provisioned with minimal management effort, often over the Internet. Cloud computing relies on sharing of resources to achieve coherence and economies of scale, similar to a public utility.
• Cybersecurity - The protection of computer systems from theft or damage to their hardware, software or electronic data, as well as from disruption or misdirection of the services they provide.
• Modelling, Simulation, Visualization and Immersion – A set of technologies used in the design, analysis, verification and validation on a product to improve quality, processes, training techniques and situational preparedness.
• Robotics - Mechanical or electrical engineering coupled with computer science used to design, construct, operate and apply robots, including the computer systems for their control, sensory feedback and information processing. 
• The Industrial Internet of Things - The use of Internet of things technologies to enhance manufacturing and industrial processes, incorporating machine learning and big data technologies to harness the sensor data, machine-to-machine communication and automation technologies that have existed in industrial settings for years.

 

Materials used for additive manufacturing

Additive manufacturing processes are gradually increasing in their practical application, and engineers are starting to figure out where, when and how they could be the most useful.

Rather than looking to completely replace all conventional manufacturing techniques, additive manufacturing is being used selectively on projects where it can offer a real advantage. As an example, creating a large-scale item such as a building or a plane wing is seen as not being advantageous, but manufacturing the small components could provide previously unavailable benefits.

The materials which can be used will play a significant part in determining how and where the process is used, and the role in plays in the future.

 

What metals can be used for additive manufacturing?

Industrial machines have the ability to use metals; this is not really an option for home printers because of the cost. The main metals which can be used are:

• Stainless steel
• Steel
• Titanium
• Gold
• Silver

 

Bike Frame 3D printed in Titanium Alloy

In addition to using pure metals, compounds can also be used but different processes are generally required during the fusing.

Metal compounds are generally not wholly melted during the sintering process, but the particles merged. There is a distinction between these two processes as full melting means the metals all pool together and re-harden as a new compound. This provides waterproofing qualities not otherwise available.

As a general rule, metal alloys aren’t suitable for full melting because they have different melting points. Some metals which have particularly high melting points are also best sintered rather than fully melted too.

 

What thermoplastics are suitable for additive manufacturing?

Thermoplastics, or polymers, are amongst the cheapest materials that can be used and are the typical content for commercial 3D printers being sold for home use.

But despite the widespread availability of these plastics, they still offer some very real benefits.

The main thermoplastics being used are:

• Acrylonitrile butadiene styrene (ABS)
• Polylactic acid (PLA)
• Polyvinyl alcohol (PVA)
• Polycarbonate

ABS is the type of polymer which is the most widespread and can most easily be described as the type of plastic used for making Lego bricks. PLA is however starting to rise in popularity because of its flexibility, being available in both rigid and soft finishes. There’s a third type of PLA that provides a rubbery finish, remaining flexible.

  

PVA is used as a material to create supports within the Additive Manufacturing process, and is entirely dissolvable. These supports can be removed once the final design is complete and being soluble can just be washed away.

Polycarbonate is a material that is still in development as it requires a high-temperature nozzle but holds possibilities for the future.

The additive manufacturing processes allow the combination of plastics with carbon fiber. This has the advantage of strengthening the product without adding any weight to the design.

 

What Unusual Materials are Used in Additive Manufacturing?

Polymers and metals are the most common types of material used and can be used to produce moulds and functioning components. They are particularly efficient for low-volume manufacturing and minimise waste.

There are however possibilities for other materials to be used in additive manufacturing, even though their use may not be as widespread.

 

Which Medical and Biochemical Materials Can be Used?

As well as industrial manufacturing uses, there’s the possibility that additive manufacturing processes could be used in the medical field too.

Bio-ink can be created from stem cells, which are then printed and layered like other materials, forming new tissue. Exciting results have been created from this technology, with bladders, blood vessels and kidney parts all having successfully been “printed”.

It’s not just soft tissue that can be created in this way; new bone has successfully been grown too. By printing out a compound of a material made from calcium phosphate, silicon and zinc and combining this with bone cells, new bone growth was stimulated. The printed material was later dissolved, leaving just the new bone.

The pharmaceutical industry is starting to become more interested in the ability to use additive manufacturing to make drugs and medications more cheaply. At present this is just a fledgling interest and not a developed process in widespread use.

 

What does the Future Hold?

Although the technology has been around for more than 30 years, it’s only recently that the materials suitable for use and their possible functions has really expanded. There are an almost limitless number of industries that could benefit from incorporating Additive Manufacturing into the processes, changing the face of what’s possible.

 

What are smart materials?

 

Smart materials are materials that are manipulated to respond in a controllable and reversible way, modifying some of their properties as a result of external stimuli such as certain mechanical stress or a certain temperature, among others. Because of their responsiveness, smart materials are also known as responsive materials. These are usually translated as "active" materials although it would be more accurate to say "reactive" materials.

For example, we can talk about sportswear with ventilation valves that react to temperature and humidity by opening when the wearer breaks out in a sweat and closing when the body cools down, about buildings that adapt to atmospheric conditions such as wind, heat or rain, or about drugs that are released into the bloodstream as soon as a viral infection is detected.

 

Types of smart materials

Nowadays, there are different types of smart materials and new ones arise every day, thanks to investment in R+D+i. Among them, the following should be highlighted:

 

Piezoelectric materials

They can convert mechanical energy into electrical energy and vice versa. For example, they change their shape in response to an electrical impulse or produce an electrical charge in response to an applied mechanical stress.

 

Shape memory materials

They have the ability to change the shape, even returning to their original shape, when exposed to a heat source, among other stimuli.

 

Chromoactive materials

They change colour when subjected to a certain variation in temperature, light, pressure, etc. Nowadays, they are used in sectors such as optics, among others.

 

Magnetorheological materials

They change their properties when exposed to a magnetic field. For example, they are currently used in shock absorbers to prevent seismic vibrations in bridges or skyscrapers.

Photoactive materials

There are several types: electroluminescent emit light when they are fed with electrical impulses, fluorescents reflect light with greater intensity and phosphorescents are able to emit light after the initial source has ceased.

 

Examples and applications of smart materials

Materials science is a constant supply of news about new discoveries that could revolutionise our future. We review some of the most amazing materials from recent years below:

• Synthetic spider web. This material is not only five times stronger than steel, but also has great elasticity. Its potential uses include bulletproof clothing, artificial skin for burns or waterproof adhesives.
• Shrilk. Its main component is chitin, a carbohydrate found in krill shells. It was created by researchers from Harvard University and is considered the ideal substitute for plastic — since its decomposition time is only two weeks and it also works as a stimulant for plant growth —.
• Graphene. Its potential uses are almost unlimited: batteries with more autonomy, cheaper photovoltaic solar cells faster computers, flexible electronic devices, more resistant buildings, bionic limbs, etc. All this is possible thanks to their multiple properties.

 

Future scope of smart materials

Worldwide, considerable effort is being deployed to develop smart materials and structures. The technological benefits of such systems have begun to be identified and, demonstrators are under construction for a wide range of applications from space and aerospace, to civil engineering and domestic products.

This was a brief write-up about the materials for industry 4.0 which will help one in getting an idea about the topic.

Thank you.