Additive Manufacturing 3D Printing

The Additive Manufacturing 3D Printing process is essentially an industry term that refers to 3D printing, a process by which physical, three-dimensional products are created directly from a computer design file by depositing materials in layers.

3D Printing Computer Aided Design (CAD) and Additive Manufacturing — 3D Printing – D&D Enterprises of Greensboro, Inc. USA

3D Computer Aided Design (CAD) and Additive Manufacturing

Computer aided design (CAD) is a highly innovative process which utilizes computers to create illustrations or technical drawings for a wide range of industries. CAD has revolutionized modern manufacturing by allowing visualization of projects and designs through computerized models that can be adjusted to correct problems before a physical prototype is created. Common types of CAD include metal fabrication, 3D printing, and others that have significantly impacted modern manufacturing as well as other business processes.

A Transformative Design Tool

3-dimensional CAD, or 3D CAD, is a transformative design tool that allows for the creation of realistic 3D images (3D models) which can be rotated and viewed from any direction. In addition to the enhanced visual capabilities, 3D CAD offers the customer a quick turnaround in the product design.

Additive Manufacturing 3D Printing Process

The Additive Manufacturing 3D Printing process is similar to the way desktop printers produce images, but instead of using ink, 3D printers use a wide range of materials including polymer composites, metals, thermoplastics, and much more. Because of the vast options of materials that can be utilized, additive manufacturing allows for the creation of lighter and stronger parts and systems.

Since its inception, terminology describing the process of using a CAD software and a printer to create objects layer by layer has included:

3D printing
Additive manufacturing,
Freeform fabrication
Layered manufacturing
Direct digital manufacturing

3D Computer Aided Design (CAD) and Additive Manufacturing

Benefits of Additive Manufacturing

Additive manufacturing can improve energy productivity, therefore reducing energy use by 25%. By cutting waste significantly and using less material for the final product, the cost of materials can be decreased by up to 90% compared to other, more traditional manufacturing methods. Additive manufacturing provides not only the opportunity to create realistic prototypes, but also the final components.

Other benefits of additive manufacturing include:

Greater design flexibility
Rapid prototyping
Decreased production time/fewer production steps
Elimination of the limitations of subtractive manufacturing
Efficient use of common materials for low-volume manufacturing
Greater sustainability compared to traditional production technology
Product weight reduction options
Creation of high-impact job opportunities

How the Process Works

Additive manufacturing refers to the creation of three-dimensional objects one fine layer at a time. Each successive layer of material (melted or partially melted) is bonded to the previous layer. Computer aided design software is used to create specialized files (.stl files) which essentially divide, or “slice”, the product into many ultra-thin layers. Using the information from the files:

The print head or nozzle is guided to precisely deposit material layer after layer, or
An electron beam or laser partially or completely melts the additive manufacturing powder which fuses together to make a 3D product when it cools

Types of additive manufacturing vary depending on the material and machine technology that is utilized including:

VAT photopolymerization: Layers of liquid photopolymer resin are used to construct the product. Stereolithography (SLA) and digital light processing (DLP) are vat photopolymerization processes that can be used to create some of the most complex, detailed 3D prints. SLA technology is commonly used for jewelry molds, hearing aids, and orthodontic aligners.
Material jetting: Similar to reproduction by an inkjet printer, a print head deposits droplets which solidify layer by layer. Each liquid photopolymer layer is cured with UV light. Material jetting can be used for both prototyping and end-use parts.
Material extrusion also called fused filament fabrication (FFF)): This common 3D printing technology involves heating the drawn material (usually plastic filament) into a nozzle and then depositing it layer by layer. Material extrusion is especially well-suited for prototyping (rough idea to functional prototype) as well as some end-use production applications.
Binder jetting: This process utilizes a powder-based build material and a liquid binder. The print head moves horizontally depositing alternating layers of the two. Binder jetting can use metal to create prototypes or finished parts or may use sand materials to create molds.
Sheet lamination: Sheets/ribbons of material are bonded together using ultrasonic additive manufacturing (UAM) for metal or laminated object manufacturing (LOM) for paper or plastics. Material costs, especially for paper, can be quite low for sheet lamination, making it particularly suitable for prototyping.
Powder bed fusion (PBF): This common AM process uses thermal energy, such as lasers and electron beams, to fuse regions of a powder bed. Types of PBF processes include direct metal laser sintering (DMSL), selective heat sintering (SHS), selective laser sintering (SLS), selective laser melting (SLM), and electron beam melting (EBM).
Directed energy deposition (DED): Often utilized to maintain and/or repair existing structures, the DED laser melts the materials as they are deposited.

Additive Manufacturing Materials

Plastics

Plastics are the most common material used in additive manufacturing from prototypes to finished products. Depending on the technology being used, the polymer materials may be filament, resin, powder, or pellet.

Common 3D printable plastics include

PLA
ABS
TPU
Nylon

Benefits of plastic include its versatility, strength, and flexibility. Engineering-grade polymers also allow for high-performance final product creation such as those used in the aerospace industry.

Metals

Metals such as aluminum, stainless steel, Inconel, and steel alloys are becoming widely used in additive manufacturing. Metal-infused plastic filaments also enable metal production on 3D printers. When metal materials are used, sintering and smoothing processes are often utilized to achieve the right finish.

Ceramics

Ceramic materials are generally biocompatible and heat resistant, therefore able to be used for a variety of industries, such as medical or artistic applications. Post-processing procedures such as firing are typically done to finish a ceramic 3D print.

Pastes

A wide variety of paste materials of can be dispensed through a syringe cartridge system allowing the end-product to be completely flexible or mixed with a harder layer if desired. Types of paste materials include:

Silicone
Clay
Metal powder
Concrete
Magnetic
Resin
Plaster
And many more

Rapid Prototyping

Regardless of the end-product desired, rapid prototyping offers an inexpensive method to test functionality and performance. Production-grade thermoplastics (such as PC and ABS) are utilized for prototypes that require resistance to mechanical, thermal, or chemical stress. Rapid, functional prototyping allows our clients to move forward into full production with confidence.

Rapid functional prototyping allows you to:

Quickly and cost effectively test product performance during development
Refine and perfect the product before mass manufacturing
Keep intellectual property in-house

Rapid prototyping techniques include:

Stereolithography (SLA): UV light applied to a photopolymer resin causes it to solidify. SLA works well when producing watertight and/or clear parts.
Selective Laser Sintering (SLS): A high powered laser fuses a powdered material (often nylon which is extremely strong) into a 3-dimensional shape.
Fused Deposition Modeling (FDM): Thermoplastic resin layers are applied in a cross pattern which hardens as it cools. FDM is often the least expensive method to use.
Direct Metal Laser Sintering (DMLS): Similar to SLS, a laser fuses powder into a solid material, however, DMLS involves metallic powders which makes the application durable enough for functional prototypes and end-use products.

Post-Processing and Finishing

Post-processing is a step that is often necessary in additive manufacturing. Our goal is always to produce the right finish every time on every product for every client. Post-processing steps required will depend on the 3D application used, product materials, and the desired end properties.

Common post-processing steps we offer:

Unpacking (removing the parts from the powder bed)
Powder removal (cleaning off excess powder)
Support removal (cleanly removing 3D supports)
Curing (allowing solidification, often with UV light)
Firing (firmly sets and solidifies ceramic designs)
Sintering (fuses all metal content and removes non-metal to produce the desired size)
Assembling (typically for large builds, manually putting multiple pieces together)
Polishing (shining the finished surface)
Smoothing (removing the layer lines to create a smooth finish)
Dyeing/painting (application of dye or paint)

Our design and manufacturing experts have the necessary expertise and experience to create your designs from a wide range of materials to your exact specifications. Our state-of-the-art equipment and streamline fabrication systems reduce turnaround time and allow you to get your prototypes and/or components quickly and cost-effectively. Turning designs, both large and small, into reality is our commitment to our clients.