Silicone is a relatively new material in 3D Printing. Due to high viscosity of the material, it took time to develop this material for 3D Printing. Silicone can be 3D Printed using SLA technology. Silicone is an elastomer and unlike thermoplastics, it can’t return to liquid state after being solidified.
Properties & Applications Of Silicone:
– Excellent thermal stability, up to 200°C and as low as -80°C
– Repels water and is resistant to steam
– Ideal compression set for forming tight seals
– UV resistant
– Electrical insulator, even under water
– Tear resistant
– Transparent, ideal for optics
– Can be sterilized
– Flame retardant
– Food safe
Those properties lend silicone to be found in a wide range of industries, such as manufacturing, energy, food production and handling, automotive, aerospace, consumer goods, healthcare, electronics and agriculture. Everything from gaskets and tubes to keypads and switches are made from silicone rubbers. The sound dampening devices in cars and the black boxes in airplanes are also made from the material.
Comparison with Liquid Silicone Rubber (LSR):
Using liquid silicone rubber (LSR) to manufacture molded parts has been around for long time. LSR provides a shore hardness of 30A to 70A. It gives a smooth texture, offers multiple colors and is primarily used in high volume prototyping pilot runs and end-use production parts.
Limitations of 3D Printing with Silicone:
Currently, the parts that can be 3D Printed are modest in size. Parts must be no larger than 4.7 in. by 2.8 in. by 3.9 in. (119.38mm x 71.12mm x 99.06mm). Color choice is either translucent white or black for 60A. So, if one is looking for color parts then molding is the best bet. That said, if your aim is simply to test design integrity, color might be irrelevant.
One other important consideration that is pertinent to all transitions from printing to molding is if you are planning to use 3D Printing as a prototyping step and move on to molding for on-demand manufacturing quantities, make sure your designs are moldable before putting special features into the parts.
Last, but not least, is cost. While printing in silicone is not inexpensive compared to other printing options and materials, it is less expensive than paying for a mold, and possible iterating with multiple molds. So, silicone isn’t cheap, but it is a good option for saving money during prototyping, and possibly throughout a part’s life cycle.