Article

Know your materials:
SIL

Silicone (SIL), is an additive material specifically developed by Carbon® for its digital light synthesis (DLS) process. Also known as SIL 30, this silicone urethane offers a unique combination of biocompatibility, low durometer, and tear resistance. Applications that require comfort for skin contact are perfect use cases for SIL. SIL is comparable to thermoplastic elastomers with a Shore A hardness of 35.

Mechanical specifications

SIL is soft to the touch and allows the ability to print customized parts – especially wearables. It’s a specialty material that is only available for specific production applications. Below we have broken down some of SIL’s key mechanical specifications:

  • Ultimate tensile strength: 3.2 MPa
  • Elongation at break: 330%
  • Tear strength: 6 kN/m
  • Durometer: 35, Shore A

Read the Carbon SIL technical data sheet for more information.

Why SIL?

Design tools created specifically for silicon elastomers allow us to tune the performance of SIL through lattice design, allowing it to meet unique requirements in a wide range of applications. SIL prints as a rigid green-state material, only becoming flexible and elastomeric after fully curing. This is important because it allows for better “printability” than other elastomeric materials and enables engineers to produce a wide variety of geometries.

SIL lattice earpads

Popular applications

SIL’s biocompatibility, tear resistance, and softness make it an ideal candidate for comfortable skin-contact applications such as headphone pads, bike handles, and wristbands. At Fast Radius, we’ve had success using this material for grommets, small industrial bellows, and cushioning/foam replacement.

SIL handlebar grips

Getting started with SIL

If you’re interested in learning more about SIL, including lead times and design considerations, contact us today. Fast Radius aims to make new things possible every single day, and our team of specialized engineers and designers can help launch your next application.

Want to see what other additive materials we offer? Be sure to check our resource center and read about other materials including RPU 70, EPX 82, and CE.