To understand high tensile strength plastics, we must first discuss tensile strength. Tensile strength is the maximum stress a material can withstand without breaking while being pulled or stretched. Some materials will break sharply – called a “brittle failure” – while others experience some deformation before fracture. Tensile strength is one of the most important and widely measured properties of materials used in structural applications. High tensile strength plastics can take the place of metal in many applications, reducing weight and cost without sacrificing performance.
Understanding High Tensile Strength Plastics
The tensile data of plastics is determined in an ideal temperature controlled lab under short-term conditions, whereas real-world operating environments apply loads over time with variable temperatures. When heat is combined with load, some plastics exhibit creep (a tendency to slowly lengthen, yield and deform), which can make tensile data potentially misleading. To compensate for this, engineers also consult the tensile modulus (modulus of elasticity), which is the ratio of stress to strain below the yield point of the material. By designing to a stress level below the tensile modulus, plastic components are more likely to function within their practical operational limits.
Top 4 High Tensile Strength Plastics
- PAI – Polyamideimide (PAI) boasts the highest tensile strength of any plastic at 21,000 psi. This high performance plastic has the highest strength of any unreinforced thermoplastic, good wear and radiation resistance, inherently low flammability and smoke emission, and high thermal stability. PAI parts can be found in engines, valves, gears, electrical connectors, and thrust washers.
- Ultem® – Also known as PEI, Ultem® has a tensile strength of 15,200 psi and an excellent combination of mechanical properties. It is easily machined and fabricated, has excellent strength and rigidity, a high dielectric strength, and a continuous use temperature of 340ºF. PEI is often used in medical and chemical instrumentation due to its heat, solvent, and flame resistance.
- PEEK – One of the best high performance engineering thermoplastics on the market, PEEK has a superior mix of mechanical properties, including a tensile strength of 14,000 psi. It can withstand high temperatures (up to 480ºF for continuous use), has inherently good wear and abrasion resistance, and offers excellent chemical and hydrolysis resistance. PEEK can be found in the most demanding applications and harshest environments, such as aircraft parts, bearings, pumps, and medical implants.
- Nylon – An honorable mention goes to Nylon, with a tensile strength of 12,400 psi. This high tensile strength plastic can often be overlooked, but it has a relatively high melting point (450ºF) and exhibits excellent abrasion resistance. It also has high chemical resistance and is not damaged by oils, solvents or alcohols. Nylon is used in a wide array of applications, from compound bow strings to substituting for low strength metals.
We Excel at High Tensile Strength Plastic Parts
Reading Plastic has been machining and fabricating high tensile strength plastic parts for over three decades. Our parts can be found in a wide variety of industries and applications around the world. For precisely machined plastic parts, call the experts at Reading Plastic today: 610-926-3245.
