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Teralink™ S, a material for mechanical parts, offers high wear resistance and fatigue strength.

Using the core technology of Sumitomo Electric Fine Polymer, Inc., designed to improve material properties through electron beam irradiation, Teralink™ S is produced for use in engineering plastic parts with increased fatigue strength.

Product Data
  • Start of sales: June 2014
What is Teralink™

What is Teralink™ S?

Teralink™ S is an engineering plastic used to construct components for industrial machines, gears for motor-assisted bicycles, and other items. Injection-molded*1 parts irradiated by electron beams form cross-linked*2 polymer chains for improved wear resistance and fatigue strength. Our customers have remarked that the use of Teralink™ S with increased fatigue strength to construct gears to replace original metal gears has helped them achieve cost and weight reductions.

Injection molding: A processing method used to build a product by injecting molten plastic into a mold, followed by cooling and solidification
Cross-linking: A technique used to modify polymer properties by introducing cross-links in the molecular structure of the polymer

What are the features of Teralink™ S?

This product features excellent wear resistance and high fatigue strength. Nylon 66, POM*3 and Teralink™ are widely used as a material for plastic gears. The results of durability tests for gears made of these materials are shown below. In contrast to nylon 66 and POM, Teralink™ S neither develops tooth wear nor decreases in weight even under a triple or higher tooth surface load, which is an indicator of fatigue strength. These features imply that to achieve the same level of strength, Teralink™ S gears can be smaller and provide more space savings than those made of other materials. Thus, our customers in the industrial machinery field place high expectations on Teralink™ S.

Gear durability test (no lubrication, 100 h)
POM: An abbreviation for polyacetal. POM is the most abundantly used material for plastic gears.
Interview with engineer in charge
Shohei Okabe
Teralink Section, Optical Component Business Promotion Dept.
Sumitomo Electric Fine Polymer, Inc.
Shohei Okabe

What motivated you to develop Teralink™ S?

To begin with, it is a well-known fact that the irradiation and cross-linking process improves the heat resistance of plastics. Indeed, we began to manufacture and sell Teralink™ not for gear applications, but for heat-resistant parts. Meanwhile, one of our customers asked us if it would be possible to use Teralink™ in gears. Then we constructed a sample. It was the beginning of the development of Teralink™ S.

After examining it, the customer rated the sample very highly.

When we built the sample, we had no idea why Teralink™ S was suitable for gears. We measured it to obtain every physical property such as in a plastics engineering catalog. However, the reason for the material’s effectiveness in gears was still unclear. We almost gave up, believing that the sample’s effectiveness was just a coincidence. Nevertheless, we asked ourselves another question, which was: What were the important properties of gears? When we measured the material’s fatigue strength by subjecting it to the repeated application of a weak force, we realized the substantial effects of the process. We built another gear and tested its durability. The test proved that the irradiation and cross-linking process made gears tough, enabling them to endure the application of a three times higher force. Thus we decided to manufacture and sell the product under the name Teralink™ S.

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