PEEK Rod: The Complete Guide to Polyetheretherketone Round Bar

PEEK rod, short for polyetheretherketone round bar, is one of the highest-performing engineering plastics available today. It is the material engineers turn to when standard plastics such as nylon, acetal (POM) or even PTFE cannot survive the combination of heat, chemicals, wear and mechanical load found in demanding industrial environments. In this guide, we explain what PEEK rod is, its key properties, the available grades and sizes, its main applications, and how to choose a reliable PEEK rod manufacturer.

What Is PEEK Rod?

PEEK is a semi-crystalline thermoplastic polymer belonging to the polyaryletherketone (PAEK) family. It was first commercialized in the early 1980s and quickly became the benchmark high-performance plastic for extreme applications. PEEK rod is the semi-finished bar stock extruded from PEEK resin, available as round bar, plate, and tube, which machine shops and manufacturers convert into finished components.

What makes PEEK special is its molecular structure: a rigid aromatic backbone connected by ether and ketone groups. This structure delivers an unusual combination of high strength, thermal stability and chemical resistance that very few plastics can match, earning PEEK the reputation of the highest-performing melt-processable thermoplastic.

Key Properties of PEEK Rod

High-temperature resistance. PEEK rod maintains its mechanical properties at continuous service temperatures up to 260°C (500°F), with a heat deflection temperature up to 316°C under load. Its melting point is 343°C and glass transition temperature 143°C, significantly higher than most engineering plastics.

Excellent chemical resistance. PEEK resists a wide range of chemicals including acids, alkalis, hydrocarbons, steam and hot water. At room temperature it is insoluble in almost all solvents except concentrated sulfuric acid, and it resists hydrolysis with very low water absorption (0.07%).

Outstanding mechanical strength. Virgin PEEK rod offers tensile strength of 95MPa; carbon-fiber-reinforced PEEK CF30 reaches 250MPa with a tensile modulus of 23GPa, metal-like performance at a fraction of metal’s weight, with excellent fatigue resistance under alternating stress.

Superior wear resistance. Self-lubricating and abrasion-resistant, PEEK rod runs unlubricated in bearings and wear pads. Bearing-grade PEEK with PTFE and graphite reaches a friction coefficient as low as 0.18, and CF30 as low as 0.15.

Dimensional stability. Low moisture absorption and a low thermal expansion coefficient (as low as 15 ppm/K for CF30) keep machined parts within tolerance across temperature and humidity changes.

Inherent flame retardancy. PEEK is rated UL94 V-0 and self-extinguishes even without flame-retardant additives, making it suitable for aerospace and electrical applications where fire safety is mandatory.

Radiation resistance. PEEK withstands high gamma radiation, up to 1100 Mrad, while maintaining good insulation, a rare combination among polymers.

Sterilizable and FDA-compliant. PEEK withstands steam, dry heat, ethanol and gamma sterilization, and virgin grade raw materials meet EU and US FDA food-contact regulations.

Grades and Types of PEEK Rod

HANSA manufactures the complete range of PEEK rod grades:

Natural virgin PEEK rod: the standard all-round grade with the best toughness and impact resistance (no-break in unnotched Charpy testing). Natural (brown-grey) or black. Diameter Ø3–300mm.

PEEK GF30 rod (30% glass fiber): roughly twice the stiffness and better creep resistance and dimensional stability for structural parts under continuous load. Natural or black, Ø5–260mm.

PEEK CF30 rod (30% carbon fiber): the highest mechanical performance: 250MPa tensile strength, 23GPa modulus, electrically conductive for ESD applications, and 3.5x the thermal conductivity of unreinforced PEEK for fast heat dissipation from bearing surfaces. Black, Ø5–180mm.

Bearing-grade PEEK rod (carbon fiber + graphite + PTFE): optimized friction properties (low coefficient, high pressure limit) for bearing and wear applications. Black, Ø5–180mm.

ESD PEEK rod: antistatic grade for electronics handling and cleanroom environments. Black, Ø5–260mm.

Sizes and Customization

PEEK rods are available from Ø3mm to Ø300mm in standard lengths of 1000mm, 2000mm and 3000mm, with nearly 100 die sizes and continuous-extrusion lines that keep common specifications in stock. Custom diameters, longer lengths and cut-to-size service are available on request. For large components, big seals, valve seats, pump housings, large-diameter bars let you machine the entire part from one piece, eliminating joints and weak points.

Applications of PEEK Rod by Industry

Aerospaziale: interior fittings, valve components and lightweight structural parts meeting strict flame-retardancy and weight requirements, with AS9100D-certified traceability.

Medical & pharmaceutical: surgical instrument components, sterilization baskets and food-contact parts that withstand repeated sterilization and FDA scrutiny.

Semiconductor & electronics: wafer-handling rings, insulation sleeves, test fixtures and ESD-safe parts that survive plasma, chemicals and thermal cycling.

Oil & gas and chemical processing: seals, valve seats, pump gears and back-up rings that resist sour gas, hydrocarbons and aggressive media.

Automobilistico: engine and transmission components, bearing cages and seals that perform at high under-hood temperatures, produced under IATF16949 quality systems.

Analytical & testing instruments: chromatography components and precision instrument parts demanding chemical inertness and dimensional precision.

PEEK Rod vs. PTFE vs. Other Plastics

PEEK and PTFE are often mentioned together, but they solve different problems. PTFE offers the ultimate chemical inertness and the lowest friction coefficient, yet it is soft, deforms under load, and has limited mechanical strength. PEEK rod is far stronger, stiffer and harder, with better wear resistance, lower creep, and a higher load-bearing capacity at elevated temperatures. Compared with nylon or acetal, PEEK operates at temperatures 150–200°C higher and resists chemicals they cannot tolerate. The trade-off is price: PEEK costs roughly 10–20 times the cost of acetal, but when a component fails repeatedly in service, the longer life and reduced downtime of PEEK usually win on total cost of ownership.

Machining PEEK Rod

PEEK rod machines cleanly on standard CNC lathes and mills. Key rules: use sharp carbide tools, adequate cooling to prevent heat buildup, and account for PEEK’s thermal expansion when holding tight tolerances. For best surface finish and accuracy, rough and finish passes are recommended. HANSA runs 4-axis / 5-axis CNC and mill-turn centers with CMM inspection to 0.003mm and vision measuring to 0.001mm, so customers can order PEEK rod either as bar stock or as fully machined finished parts.

How to Choose a Reliable PEEK Rod Manufacturer

Quality varies significantly between manufacturers, and PEEK rod is too expensive to risk on a bad batch. Look for:

Integrated production capability: a manufacturer with the complete chain: resin polymerization, modification, extrusion and machining.

Certified quality systems: AS9100D (aerospace), IATF16949 (automotive), ISO13485 (medical), ISO9001, FDA, RoHS and REACH.

Documented quality: COA and dimensional inspection reports with every order, plus a strict “no unqualified raw material in, no unqualified product out” principle.

Full size and grade availability: one supplier for virgin, GF30, CF30, bearing-grade and ESD rods from Ø3mm to Ø300mm.

Machining capability: in-house CNC means the manufacturer understands how PEEK behaves on the machine and can deliver finished parts, not just raw bars.

Reliable delivery: stock availability for standard sizes, clear lead times, and experienced international logistics partners.

Why Buy PEEK Rod from HANSA

HANSA has specialized in high-performance engineering plastics since 1995 and has dedicated 20 years to PEEK R&D and production, operating a 16,000-square-meter production base with 40 continuous extrusion lines, 500+ professional staff and 30,000+ solutions delivered. Standard PEEK rod sizes ship within 7 days; custom diameters, reinforced grades and machined parts are delivered to an agreed schedule. Every order is packed in wooden crates with foam padding and shipped via FedEx, DHL or UPS, with a professional sales team of 20+ years’ industry experience supporting you from inquiry to installation.

If your application demands high temperature, chemicals, wear resistance and precision, PEEK rod is the answer, and HANSA is ready to supply it. Send us your drawings and requirements for a free quote and free sample.