ADDITIVE MANUFACTURING

"Additive manufacturing (AM) or additive layer manufacturing or 3D printing, a computer controlled process that creates three dimensional objects by depositing materials in the form of layers or fine droplets."

It is defined as additive because the material is added sequentially, as opposed to more traditional (subtractive) manufacturing where material is removed from a solid block until the final part is left.

The concept had been around since the 1940s, Hideo Kodama of the Nagoya Municipal Industrial Research Institute developed the earliest 3D printing manufacturing equipment in 1980, when he invented two additive methods for fabricating 3D models.

History of Additive Manufacturing

1940s and 1950s

The general concept and procedure to be used in 3D-printing was first described by Murray Leinster in his 1945 short story Things Pass By.

1970s

Johannes F Gottwald patented the Liquid Metal Recorder. It was continuous Inkjet metal material device.

1980s

In April 1980, Hideo Kodama of Nagoya Municipal Industrial Research Institute invented two additive methods for fabricating three-dimensional plastic models with photo-hardening thermoset polymer, He filed a patent for this XYZ plotter, which was published on 10 November 1981.

1981

A Patent on the Method of Fabricating Articles by Sequential Deposition.

1984

American entrepreneur Bill Masters filed a patent for his Computer Automated Manufacturing Process and System.

1984

Alain Le Méhauté, Olivier de Witte, and Jean Claude André filed their patent for the stereolithography process.

1993

The term 3D printing originally referred to a powder bed process employing standard and custom inkjet print heads, developed at MIT.

1995

Fraunhofer Society developed the selective laser melting process.

2009

Fused Deposition Modeling (FDM) printing process patents expired.

2012

Filabot developed a system for closing the loop with plastic and allows for any FDM or FFF 3D printer to be able to print with a wider range of plastics.

2014

Benjamin S. Cook and Manos M. Tentzeris demonstrate the first multi-material, vertically integrated printed electronics additive manufacturing platform (VIPRE) which enabled 3D printing of functional electronics operating up to 40 GHz.

Additive manufacturing steps

The following 8 common steps in every additive manufacturing processes.

Step 1 – 3D model creation
Step 2 – STL file creation
Step 3 – STL file transfer
Step 4 – Machine set up
Step 5 – Build
Step 6 – Part Removal
Step 7 – Post processing
Step 8 – Applications

Additive manufacturing technology

There following 7-AM technologies are-

1. Vat Photo Polymerization
2. Binder jetting process
3. Directed energy deposition
4. Material extrusion
5. Material jetting
6. Powder bed fusion
7. Sheet lamination

Advantages of Additive Manufacturing

1. Complex 3D geometries with internal features can be printed without any tooling.
2. Reduced waste compared to machining.
3. Part can be printed directly from the 3D model without the need for a drawing.
4. Prototypes can be made quicker allowing designers to check different iterations resulting in a quicker design cycle phase.
5. Less tooling for smaller batches compared to traditional machining.
6. Production tooling can be printed.
7. Different materials can be mixed during the printing process to create a unique alloy.
8. Different sections of the part can be a different variants of the same alloy.

Disadvantages of Additive Manufacturing

1. Because the technology is still in its infancy the build process is slow and costly.

2. High production costs because of the equipment cost.
3. Various post-processing required depending on the type of additive manufacturing used.
4. Small build volume compared to other manufacturing part size such as sand casting.
5. Poor mechanical properties hence need post-processing.
6. Poor surface finish and texture.

Applications of Additive Manufacturing

1.Aerospace Industry
2.Automotive Industry
3.Machinery (e.g.Turbines, Special Machinery)
4.Medical implants (Dental,Orthopedic)
5.Handling and Robotics
6.Lifestyle & Sports (e.g.Jewelry,Biking)
7.Custom Parts (e.g. Classic Car Parts, Surgical Tools)

8. Architectural Engineering
9. Toys Industries
10. Jewelry
11. Art