High-Strength Plastics – 4 Ways To Measure Strength

Throughout our blog, you may have noticed many references to strength. In particular, we’ve discussed high-strength plastics like PEEK, Celazole PBI, Vespel, and Techtron PPS. Each is unique in its strengths, as well as the other benefits it brings to the table (such as UV resistance, conductivity, resistance to friction, just to name a few.) But what, exactly, do we mean by “strength”?

Actually, there are some industry standards plastics manufacturers use to measure the strength of plastics. In this blog, we’ll break down these standard measurements—and the plastics that dominate each.

Measuring High-Strength Plastics

• Flexural strength. How well does the material resist deformation under load? This number indicates the load required to cause a given test sample to show a 5% deformation/strain of its outer surface. Some of the best plastics for flexural strength include PPS, PEEK, and PAI.
• Tensile strength, a.k.a. ultimate tensile strength. How much stress can a plastic withstand without breaking when it’s stretched or pulled? Some of the best plastics for tensile strength are PEEK, Nylon (6 cast), PAI, and VESPEL.
• Izod impact strength, a.k.a. toughness. What is the resistance of the material to an impact? The unit indicates how much energy it takes to cause the material to fracture upon collision. Some of the best plastics for Izod impact strength are polycarbonate, LPDE, UHMW-PE, Polypropylene, PAI, and VESPEL.
• Tensile modulus, a.k.a. Young’s modulus, a.k.a. stiffness. How much elasticity does the plastic demonstrate under tension or compression from a single direction? Named after 19^th-century scientist Thomas Young, this measurement shows if the plastic is elastic or rigid. One of the best plastics for stiffness is PEEK.

These are just a few of the most important measurements of strength. Others include shear strength, Rockwell hardness, and elongation at break.

It’s important to note that the strongest plastics are often filled. Filled plastics are created to add desired characteristics to the material, such as conductivity or a change of color. When it comes to adding strength, the only way to accomplish this in plastic is to add fibers.

Need Help Choosing a Strong Plastic?

If your application requires the strongest plastic parts on the market, you’ve come to the right place. At Reading Plastic, we’re experienced machining the most high-end plastics available, from PEEK to Vespel and beyond.

Reach out to us for help determining the right plastic for your application. We’ll not only guide you to the appropriate material; we can machine and fabricate your parts to tight tolerances. We can’t wait to talk about your project: (610) 926-3245!