What is PEEK Material?
Polyetheretherketone, better known as PEEK, is a semi-crystalline, high-performance, rigid engineering thermoplastic material with various beneficial properties and an excellent resistance to cruel chemicals.
PEEK material is commercially available since the 1980s, and after that, there’s no looking back. Tremendous mechanical properties, resistance to wear, fatigue, and high temperature up to 260°C make PEEK one of the most resilient and highly utilized thermoplastic materials in plastic industries.
It is one of the smoothest materials for processing in almost every vertical; however, because of its resilient properties, it is mostly utilized in industries like oil and gas, aerospace, automotive, electrical, biomedical, and semi-conductor applications.
Polyetheretherketone can be processed in traditional plastic manufacturing methods like injection molding, extrusion molding, compression molding, etc.
Properties of Polyetheretherketone –
Here are the typical properties of PEEK:
|Melting Point||°C||343 – 387|
|Coefficient of Thermal Expansion x 10-5||cm / (cm °C)||4.5 – 5.5|
|Thermal Conductivity||W / mK||0.29|
|Heat Deflection Temperature, 1.8 MPa||°C||152 – 172|
|Rockwell Hardness, M Scale||–||M100 – M124|
|Tensile Modulus at 23 C||MPa||3725|
|Tensile Strength, Yield at 23 C||MPa||100 – 115|
|Tensile Strength, Break at 23 C||MPa||–|
|Flexural Modulus||MPa||4065 – 4275|
|Break Elongation||%||15 – 45|
|Izod Unnotched||kJ / m2||No breaking|
|Dielectric Strength||V/mm x 104||2.5 – 3.3|
|Dielectric Constant @ 1 MHz||–||2.8 – 3.3|
|Dissipation Factor @ 1 MHz||–||0.001 – 0.005|
|Mold Shrinkage||%||1.0 – 1.3|
|Processing Temperature||°C||370 – 400|
|Water Absorption, 24 hr. Immersion||%||0.05 – 0.2|
- PEEK showcases magnificent creep resistance. When reacted with flexural and tensile capabilities, it gives a great balance of several mechanical properties that can withstand high loadings for an elongated period of time without residual damage.
- PEEK also boasts impressive tensile strength even in high temperatures upto 299°C. To achieve maximum results with retained properties, the polymer should be reinforced with carbon fibers. Uplifting the tensile strength somewhere between 25000psi to 30000 is quite achievable.
- The polymer can show promising insulating properties in varieties of different temperatures and environments.
- The polymer’s crystalline structure supports high resistance with multiple ranges of liquid and fabulous fatigue performance.
- The polymer’s spiral geometry helps it with reinforcing glass or carbon reinforcement, which will improve the polymer’s thermal conductivity.
- Besides being manufacturer-friendly, it is also environment-friendly, with a V0 flammability rating down to 1.45 mm and an LOI of 35%. Its generation of toxic gases and smoke is quite low compared to other mainstream thermoplastic materials.
Key Benefits of PEEK –
- PEEK’s toughness and rigidity and excellent fatigue resistance make its strength comparable to alloys.
- It has great sliding properties making it suitable for rigorous applications with low-coefficient of friction and abrasion.
- Terrefic chemcial and corrosion resistance.
- PEEK boasts one of the best flame resistance properties of most other thermoplastics with the size of 1.45mm it doesn’t need any flame retardants.
- Peeling resistance also increases PEEK’s applicability in harsh conditions and makes it easy to make with these wires and magnet wires.
Limitations of PEEK –
As discussed above, everything about PEEK seems perfect, but that’s not the case. It has great properties and multiple applications but also has some limitations which need to be discussed.
- Processing at high temperatures may not be suitable for everyone.
- UV light resistance is quite low.
- The mechanical properties make the polymer expensive and applicable for high-tech applications. PEEK even may prove a drag for manufacturing simple components.
How is PEEK Material Manufactured?
Bisphenolate salts are the main ingredient for PEEK. A process called step-growth polymerization using dialkylation is responsible for the manufacturing of PEEK.
4,4’-difluorobenzophenone is blended with hrdrocloroquinone and alkali carbonates. After the reaction is completed, PEEK is secluded by removing alkali metal fluoride and the polymerization solvent.
The prime reason for possessing such high thermal transitions and mechanical properties is the stiff aromatic polymer backbone. Thus, the polymer can be used at high temperatures, such as 240°C.
Popular Applications of Polyetheretherketone (PEEK) –
PEEK Plastic is one of the most utilized thermoplastic materials in industries like aerospace, automotive, biomedical, electrical, etc. Its might and vigor make it suitable for manufacturing bearings, insulation cables, safety gears, pumps, heavy machine parts, valves, compressors, semiconductors, etc.
Let’s dive into some of the verticals applications in detail.
Products and components made up from PEEK are steadily replacing aluminum and other metals in the aerospace industry. There are many components in the aerospace market with acceptable tolerances manufactured more cost-effectively.
- Crucial engine parts can be produced with intricate designs, as Polyetheretherketone can withstand high temperatures. Elements with needs of high lubrication, inter-biological reactions to different scenarios.
- For the interior part, the polymer can heavily reduce smoke and gas emissions. Fire resistance will also play a major part in providing safety.
- For the exterior part, PEEK will be beneficial as it can provide great rain erosion. Even here, wear and tear resistance properties will come in handy to protect the plane’s exterior part for the long term.
Healthcare products are about safety, comfort, and mobility. Polyetheretherketone can manufacture cost-effective, wear, tear, chemical, and heat resistant products. Its applications mostly include dental instruments, and safety guards, endoscopes, thermometers, and dialyzers.
- Out of many products that PEEK has replaced, dental syringes, which PEEK manufactures, become lighter and cost-effective than aluminum and metal.
- Sterile boxes, mechanical limbs, tooth, load-bearing implants are other products that PEEK actively manufactures.
- PEEK offers fantastic resistance to stress crack and mechanical strength to deal with chemicals, steam, water, and other solvents always openly available at hospitals and clinics.
PEEK plastic already has a significant presence in the electronics market. Household products like Mobile phones, cables, setup boxes, refrigerators, ACs, washing machines, computers, laptops, and electronic wearables. In some way, all these products or parts of their assembled components are produced using PEEK.
- It can be utilized for making products with fluctuation in temperature, frequency, and pressure.
- Great mechanical properties will maximize safety and comfort while handling silicon wafers.
Apart from those applications, PEEK also takes over other markets in the sectors like FMCG, hospitality, chemicals, packaging, transportation, and logistics.
Processing of PEEK Material –
PEEK plastic can be processed in methods like Injection molding, extrusion, and compression molding; however, molding conditions can heavily affect its mechanical properties.
Before processing it drying for at least 3 hours at 150°C is recommended. By doing that, we can avoid molding defects.
Let’s have a check on PEEK’s processing with injection molding method –
Injection Molding –
- The advisable mold temperature is 60-190°C for adequate crystallization and eliminates warping.
- Tweaking with the temperature up to 200°C after crystallization is possible, but only when the proceed component requires high dimensional stability.
- For near-perfect production quality, our advice would be to use injection molding only to manufacture tiny components with very tight dimensional tolerances.
- The advised injection pressure is 70-140 Mpa.
- The advised mold shrinkage is Unfilled – 1.2-2.4%, Filled – 0.1-1.1%.
Let’s have a check on PEEK’s processing with extrusion method –
- The cooling temperature would be crucial in guiding the crystallinity and performances.
- When it to comes to sheet extrusion for cooling cylinder, the temperature should be 50°C from amorphous material.
- For crystalline and opaque materials cooling cylinder temperature should be 170°C.
The Future of PEEK Material –
Global PEEK market share by Application, 2018
According to a study conducted by Grand View Research, the global Polyetheretherketone market was estimated at 684.8 million in 2018. And pegged to have a CAGR of 7.2% from 2019 to 2026. Surely, things will change drastically because of the Covid-19 pandemic.
However, the medical industry’s push (due to the pandemic) and impressive growth in the automotive segment due to an increase in demand for lightweight, fuel-efficient, and less-pollution-creating vehicles.
North America, Europe, and Asia-pacific are the biggest consumers of PEEK and will further push the growth. Asia-pacific is the fast-growing region for plastic processing, let alone Polyetheretherketone, because of increased manufacturing spending and FDI.
1. Why is PEEK plastic so expensive?
Ans. Often manufacturers get surprised by the high price point of the material. The reason for the price is said to be the high compatibility with CNC milling machines.
2. Is PEEK be used in food applications?
Ans. All the PEEK grades are compliant with FDA regulation 21 CFR 177.2415. So it is safe and secure for repeated food contact.
3. Can we 3D print from PEEK?
Ans. PEEK can be easily 3D printed in the temperature range of 370°C to 450°C. The bed temperature is standard at 120°C. It should be noted that it takes a bit more time with PEEK 3D printing than other materials, but if enough time is spent, then the quality of the products will not disappoint.
4. How strong is peek?
Ans. PEEK is a strong material with a GPa of 3.6 and a tensile strength of 90 to 100 MPa.
5. What is the melting point of PEEK?
Ans. 343°C – the melting point of PEEK.
Final Words –
Thus, was my knowledge and insights on PEEK material. I hope you liked the article. I would really appreciate it if you share our reviews in the comment box.
Have a wonderful week 🙂