Additive Manufacturing e 3D Printing

What does the term “additive manufacturing” mean?

Additive manufacturing refers to a process of creating solid 3D objects using an extrusion process.

Starting from some computer-designed models, additive manufacturing technologies are able to create three-dimensional parts.

This process involves adding layers of material that, when superimposed, complete the final product, achieving the desired shape.

More conventional manufacturing techniques, also called subtractive, tend to remove material from an initial block, rather than adding it.

Traditional manufacturing methods

The transformation of raw materials into finished products is called “material processing”.

In the industrial world, production occurs through the construction of individual parts, subsequently assembled.

For the creation of individual parts, material processing proceeds through 3 methods:

-          Forming

It consists of giving a block the desired shape, with hot or cold processing. Depending on the type of material, processing methods such as casting, shaping, drawing, rolling, extrusion, and injection and compression molding are used.

-          Subtraction

This modeling technique instead consists of working a piece by removing parts of the material using a work tool. We therefore proceed through sawing, turning, milling, drilling, shearing and filing.

-          Addition

To add, on the other hand, means to assemble or connect individual pieces to obtain an assembly. Welding, gluing, sewing, screwing are some of the addition processing methods.

After processing the raw materials, the products are classified into semi-finished products, components or final products.

Materials for Additive Manufacturing

3D printing is actually a subset of additive manufacturing, although the term is sometimes used improperly.

These two terms have different characteristics, but they are both linked to evolving production methods.

“Additive manufacturing” has an industrial connotation, generally involving the conversion of computer design files into physical 3D objects.

The materials used in the production process vary based on the properties of the materials, generally they are plastic, metal and composite.

The plastic materials that are generally used in additive manufacturing are nylon, PLA, TPU, ABS and ULTEM.

They are fairly cheap and flexible plastic materials, which are better suited to the prototyping and testing phases.

The metals for this type of production appear as dissolved powders but also accompanied by binding material. An example can be 17-4PH stainless steel, A2, D2 and H13 tool steels, copper and Inconel.

Intended for versatile applications, they can be used for cold and hot working.

Another type is made up of composite fibrous materials, which combine plastics with reinforcing fibers. In this case, they offer greater support and respond more effectively to the demands of heat resistance, stiffness and durability.

The materials that additive manufacturing uses are carbon fibers, Kevlar aramid fiber, glass fiber and HSHT glass.

Additive manufacturing offers numerous advantages compared to conventional manufacturing methods, flexibility in applications and greater cost efficiency.

In addition, customizations allow a visible reduction in industrial waste and, consequently, a more positive environmental impact.