As we have already had the opportunity to analyse in the article on the current state of 3D printing in Italy, the revolution carried out in recent years by the sector has led to clear savings in terms of resources, time and money within the industrial chain, facilitating the printing process and gaining more and more market share.
However, in high-tech sectors, such as 3D printing production, it is a perpetual work in progress.
Nowadays, 3D printing means embracing a technology that simplifies processes in a wide range of fields: from the creation of precision prototypes, with lower costs, to the creation of small product parts, through to the modification of already created products for upgrading them.
The 3D printing system therefore lends itself to multiple uses, and this versatility of application has led over time to the experimentation of very different materials.
From the point of view just described, it is essential to carry out an analysis of the materials used, because not all types of materials can have the appropriate characteristics for the various production sectors; this is why today we are going to delve into the possibilities of the materials available for 3D printed production.
The evolution and adaptation to different printing contexts has brought about rapid development in 3D printer technology, which has become increasingly simple and easy to use. In this regard, the materials used for 3D printing have also changed to adapt to the new printers. At present, there are hundreds of different types of materials with a wide range of characteristics: powders, filaments, pellets, granules, resins and much more.
PLA filaments are one of the first materials to be used in the 3D printing process, a polylactic acid composition that is still the most popular choice. The feeling of 3D technology and the green approach to production is certainly expressed by this material which, as well as being easy to mix thanks to its metallic colour, is a very versatile and biodegradable thermoplastic compound with a low environmental impact.
A material that is therefore widely chosen because it is easy to handle as well as having low shrinkage and low viscosity, which facilitates the printing process.
This fairly hard material is mainly used for non-functional and aesthetic models or for medical applications (but not for prototypes).
Among the most commonly used PLAs in the industrial sector:
As we have already mentioned, the environmental component and the need to have a low impact, leads 3D printing production to the use of natural PLA filaments, i.e. completely biodegradable biomaterials such as beer, coffee or algae. The technological evolution that led to this use is also the conceptual basis on which the 3D vision is based.
In addition to completely natural filaments, there are also 3D printing filaments made from ABS, a material composed of acrylonitrile butadiene styrene, which can be used to produce lightweight, strong objects.
The food industry, on the other hand, often uses the polyethylene terephthalate filament, more popularly known as PET.
This is a thermoplastic resin used to make plastic bottles for water or containers for storing food, or any container that has to be in contact with food. Here too, the environmental component is fundamental, as PET is completely recyclable.
PET is used to make flexible objects that can withstand external stresses, such as bottles for the food industry.
The list of filaments for extrusion systems is still long, ranging from Polycarbonate, PC, one of the most versatile thermoplastic materials, to the use of thermoplastic elastomers that combine strength (such as ABS) with flexibility and are perfect for household appliances or automotive components.
Not to mention wax filaments, which, used with the injection moulding process and a mould, can painstakingly reconstruct even very small objects and are in fact useful in the field of precious objects.
Another case is that of photopolymers used in 3D printing where standard resins are used, i.e. all those materials that can be used to make functional prototypes that also require a certain amount of aesthetic form. This material produces objects with the perfect combination of aesthetics, modelling and strength.
The colours of these resins are varied; light, dark or even transparent with the special Clear resin. This resin is also often chosen for its low cost.
Among the most popular resins are the hard ones, which withstand mechanical pressure well. While if your printing priority is that the product should last over time, you can choose Durable.
The material that has heat resistance as one of its strong points is Heat Resistant resin, and if elasticity is a priority, Rubber-like materials that are very elastic and almost rubber-like should be chosen.
A good deal of innovation in 3D printing and production has been brought about by the use of metal powders, such as titanium, which is one of the most widely used materials in the medical sector (including for prostheses).
Another very innovative material is Inconel, a true nickel-chromium super-alloy that is very resistant to corrosion.
The least expensive material for 3D printing is stainless steel, which is very versatile and is used in a number of areas: from medical to industrial (automotive, aerospace, etc.).
In addition to stainless steel, it is also possible to use aluminium (a light material) or cobalt chrome, which is increasingly popular in industrial environments. Additive moulding with copper and bronze is also possible.
The latest addition to the family of 3D printing consumables, capable of demonstrating the evolution of the 3D printing process, is the plastic material optimised specifically for this type of production: technopolymers. These are high-performance engineering plastics used, especially in recent times, in the aerospace industry.
The materials that make up technopolymers are: nylon with carbon fibre and nylon with glass fibre. These filament reels are produced to very high quality standards for real performance that now exceeds all expectations.
The filaments called technopolymers are polymers with high physical and mechanical possibilities:
The characteristics listed above show us both that these materials can completely replace metals and, secondly, that they are particularly congenial to 3D printing. Their colouring can also vary, even becoming transparent when subjected to a stretching process.
From this journey into materials for 3D printing we have realised that materials could be talked about for a long time and updating is indeed perennial, but the key points on which the philosophy of production and 3D printing works is saving, both in terms of time and the environment. These factors work together towards a common goal: high performance with unprecedented quality. New frontiers await us in this field and constant technological innovation that starts with the evolution of printers and goes to the optimisation of new, or not so new, low impact materials.
