Both selective laser sintering (SLS) and selective laser casting (SLA) 3D printing processes have a number of benefits for manufacturers. Both processes are affordable, fast and able to produce highly detailed parts. Each process has its own advantages, depending on what you're trying to accomplish with your design.

 Understanding the differences between SLS and SLA 3D printing can help you decide which one is best for your project.

‍

The SLS process uses a laser to fuse powder into a solid object layer by layer. The SLS process is also called directed energy deposition (DED). The powder is first placed into a vat. Then, the printer uses a laser to sinter the material together, layer by layer. This means that only the material that's touching the laser will be fused together. After each layer is completed, the printer will move the powder slightly and then begin fusing another layer.

The SLA process works like an inkjet printer, but instead of printing with ink it uses light to solidify resin into objects. The resin is placed in a vat and then exposed to ultraviolet light through a digital projector. The ultraviolet light hardens the resin wherever it touches it, leading to an object being created one thin layer at a time.

While both processes are able to achieve high levels of detail, SLA tends to be more accurate than SLS because it doesn't use powder, which can often lead to rough surfaces and excess material in your print files.

SLS has been around longer than SLA 3D printing and has been used for creating prototypes for years before SLA was even invented.

However, since its invention in 1986, SLAs popularity has grown exponentially because of its ability to create detailed parts that are smooth enough for use as finished products. It's also. This article covers the pros and cons of each process as well as their ideal use cases. Read on to learn more about these two 3D printing processes and which is the right choice for you.

What is Selective Laser Sintering (SLS)?

SLS is an additive manufacturing (3D printing) process that uses a laser to sinter powdered materials in a bed of sand. The process uses a computer-controlled laser to selectively fuse a bed of sand, binding the sand together to build a 3D part.

The part is built up layer by layer, with each new layer being fused to the sand below it. This process is distinguished from other types of 3D printing by the fact that it uses a bed of sand as its build platform. On top of the sand is either a powder material or a special surface that allows the laser to selectively sinter the sand and not the powder.

 The sand is then removed from the part after printing is complete. Since the build platform is sand, the parts are more robust than those made by SLA 3D printing, which have a very thin layer of polymer on top of the build platform.

The SLS process was invented in 1989 by Dr. Carl Deckard at the University of Texas at Austin. This process was initially used to make complex geometries for aerospace applications and has since been applied to a variety of industries including dental, automotive, jewelry, and orthopedic prosthetics. SLS is also referred to as laser-sintering or direct metal laser sintering (DMLS).

What is Selective Laser Casting (SLA)?

SLA is a type of photochemical process that uses a UV laser to cure a photopolymer liquid resin into a solid object. The liquid resin is usually contained in a tank and pumped to the part build tray where it is exposed to the UV laser. The UV laser then causes a chemical reaction that solidifies the liquid resin.

This process is also distinguished from other types of 3D printing by the fact that it uses a liquid material as opposed to a powder. The photopolymer resin can be used to print a wide range of materials, including thermoplastics, engineering plastics, silicone, and metals.

The SLA 3D printing process has a higher upfront cost than SLS due to the need for a vacuum chamber and UV laser. But it has a higher build volume and better resolution than SLS. What’s more, SLA can produce parts that are aesthetically and structurally superior to SLS parts.

Differences between SLS and SLA 3D printing

The two processes share some similarities and are both ideal for creating functional prototypes and end-use parts. The biggest difference between SLS and SLA is the material used. SLS uses a powdered material, while SLA uses a liquid resin.

 The powdered material is used in SLS because it can withstand the pressure created by the laser sintering process. SLA uses a liquid resin because it is able to be cured by the UV laser. This means that both processes can be used to create a variety of materials.

But the SLS process is limited to using just a few materials, while the SLA process can be used to create parts with a variety of materials. The build volume is the other main difference between SLS and SLA. The SLS process has a larger build volume than SLA, making it ideal for larger parts. The SLA process has a smaller build volume, making it ideal for smaller parts.