Selective Laser Sintering (SLS)

Selective laser sintering (SLS) is an industrial 3D printing process that produces accurate prototypes and functional production parts in as fast as 1 day. Multiple nylon-based materials and a thermoplastic polyurethane (TPU) are available, which create highly durable final parts that require heat resistance, chemical resistance, flexibility, or dimensional stability. With SLS 3D printing, no support structures are required making it easy to nest multiple parts into a single build and an economical solution for when higher volumes of 3D-printed parts are required.

How Does SLS 3D Printing Work?

The SLS machine begins sintering each layer of part geometry into a heated bed of nylon-based powder. After each layer is fused, a roller moves across the bed to distribute the next layer of powder. The process is repeated layer by layer until the build is complete.

When the build finishes, the entire powder bed with the encapsulated parts is moved into a breakout station, where it is raised up, and parts are broken out of the bed. An initial brushing is manually administered to remove a majority of loose powder. Parts are then bead blasted to remove any of the remaining residual powder before ultimately reaching the finishing department.

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  • Shipped in as fast as 1 day
  • ISO 9001 and AS9100D Certified
Common Applications
  • jigs and fixtures
  • housings
  • snap fits and living hinges

Design Guidelines for Selective Laser Sintering (SLS)

Our basic guidelines for selective laser sintering include important design considerations to help improve part manufacturability, enhance cosmetic appearance, and reduce overall production time.



Selective Laser Sintering (SLS) Materials

PA 11 Black (PA 850)

PA 11 Black (PA 850) provides ductility and flexibility without sacrificing tensile strength and temperature resistance. These characteristics make PA 850 a widely used general-purpose material for functional and moving parts.

Primary Benefits​

  • Highest elongation at break of all additively manufactured nylons
  • Uniform deep-black color that showcases features and provides a clean appearance
PA 12 White (PA 650)

PA 12 White (PA 650) is a go-to material for general-purpose applications like functional and end-use parts. PA 650 is the strongest of the unfilled nylon materials and it is slightly stiffer than PA 11 Black.

Primary Benefits​

  • Economical material choice
  • Strength and stiffness
PA12 Mineral-Filled (PA620-MF)

PA12 Mineral-Filled (PA620-MF) is a 25% mineral fiber-filled PA powder. The fiber content significantly increases stiffness and HDT (up to 363 °F). It is a good material option when stiffness and high temperature resistance are important requirements.

Primary Benefits​

  • Highest stiffness of all additively manufactured nylons
  • Temperature resistance
PA12 40% Glass-Filled (PA614-GS)

PA12 40% Glass-Filled (PA614-GS) is a PA powder loaded with glass spheres that make it stiff and dimensionally stable. This material is an ideal candidate for parts that require long term wear resistance properties. Due to the glass additive, it has decreased impact and tensile strengths compared to other nylons.

Primary Benefits​

  • Long-term wear resistance
  • Increased stiffness
Polypropylene Natural

Polypropylene Natural offers chemical resistance properties that are top among the SLS and MJF material offerings. This tough and durable, yet flexible, material offers resistance to most acids and is a low weight material option.

Primary Benefits​

  • Chemical resistance
  • Durable, low weight material
TPU 70-A

TPU 70-A is a white thermoplastic polyurethane that combines rubber-like elasticity and elongation with good abrasion and impact resistance properties. The rubber-like quality of this material make it ideal for seals, gaskets, grips, hoses, or any other application where excellent resistance under dynamic loading is required.

Primary Benefits​

  • High elongation at break
  • Flexibility 

Compare Material Properties

Material Color Tensile Strength Tensile Modulus Elongation
PA 11 Black
(PA 850)
Black 7.54 ksi 261 ksi 30%
PA 12 White
(PA 650)
White 7.25 ksi 290 ksi 11%
PA 12 Mineral-Filled (Duraform HST) Light Gray 5.51 ksi 450 ksi 3%
PA 12 40% Glass-Filled
(PA 614-GS)
White 7.25 ksi 522 ksi 5%
Polypropylene Natural Natural 2.61 ksi 123 ksi 15%
TPU 70-A White 580 psi   210%
Material Color Tensile Strength Tensile Modulus Elongation
PA 12 White
(PA 650)
White 50.0 Mpa 2,000 Mpa 11%
PA 11 Black
(PA 850)
Black 52 Mpa 1,800 Mpa 30%
PA 12 Mineral-Filled (Duraform HST) Light Gray 38 Mpa 3,100 Mpa 3%
PA 12 40% Glass-Filled
(PA 614-GS)
White 50 Mpa 3,600 Mpa 5%
Polypropylene Natural Natural 18 Mpa 848 Mpa 15%
TPU 70-A White 4.0 Mpa   210%

These figures are approximate and dependent on a number of factors, including but not limited to, machine and process parameters. The information provided is therefore not binding and not deemed to be certified. When performance is critical, also consider independent lab testing of additive materials or final parts.

sls 3d printers

Our SLS 3D Printers

Our SLS equipment includes sPro140 machines, which have the world’s largest sintering build volume, and feature fully digital high-speed scanning systems, unparalleled process consistency, and closed systems for powder blending and delivery for reliable part quality. We also use sPro60 machines, which allow for multiple materials and high throughput.

Design Essentials for 3D Printing

The 3D Printing Essentials reference guide offers guidelines and key considerations when designing for industrial 3D printing processes.

3D Printing Surface Finish Guide

Download this quick reference guide that looks at all of your surface finish options across our six additive manufacturing technologies.



a metal 3D printing technician removes support structures from a DMLS part

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