Additive Manufacturing: Powdered Bed & Inkjet 3D Printing

This post was originally created in January 2017.

With all the buzz about Additive Manufacturing, or 3D Printing, in the manufacturing world today, there is a lot of mystery and confusion surrounding the common practices and techniques. So, this week’s blog post will address a common type of 3D printing known as Powdered Bed & Inkjet 3D Printing (3DP).

What is Powdered Bed & Inkjet 3D Printing?

It is actually part of a broader category, commonly referred to as a Granular Based Technique. All granular based additive manufacturing techniques start with a bed of a powdered material. A laser beam or bonding agent joins the material in a cross section of the part. Then the platform beneath the bed of material is lowered, and a fresh layer of material is brushed over the top of the cross section. The process is then repeated until a complete part is produced. The first commercialized technique of this category is known as Selective Laser Sintering, though the main point of discussion here is Powdered Bed & Inkjet 3D Printing.

Invented in 1993 at Massachusetts Institute of Technology, it was commercialized by Z Corporation in 1995. This technology uses a powdered material, traditionally a plaster or starch, and is held together with a binder.  More materials are available now, such as calcium carbonate and powdered Acrylic.

Though 3DP is a granular (or powder) based technique, it does not use a laser to create a part. Instead, a glue or binder serves to join the part. It is also worth mentioning that this type of technique is where the term 3D Printing originated from, as it uses an Inkjet style printing head.

What Are the Advantages of this Process?

This process is one of the few Rapid Prototyping Techniques that can produce fully colored parts, through the integration of inks in the binders.

In addition, the material costs for this particular technique are relatively low, due to their wide commercial availability.

Because parts are created in a bed of material, there is no need to use support structures, like in other forms of rapid prototyping. This helps to prevent secondary operations and machining.

Another advantage of the material bed is the ability to stack multiple parts into the build envelope. This can greatly increase the throughput of a 3DP machine.

What Are the Disadvantages of this Process?

3DP can be very messy. The material used is a bed of powdered material and, if not properly contained, will get EVERYWHERE. In addition, breathing in powdered materials can potentially be very hazardous to one’s health. – though most machines account for this, it is certainly something to be cognizant of when manufacturing.

Unlike other manufacturing processes, 3DP limits each part to a single material. This means parts printed on 3DP machines will be limited to those with uniform material properties throughout.

Also, these parts are typically very fragile after initial production and require a coating, usually in epoxy.

In Conclusion

There are quite a few different ways to 3D print a part, with unique advantages and disadvantages of each process. This post is part of a series discussing the different techniques. Thanks for reading!

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