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PEEK (Polyether Ether Ketone)

PEEK — highest-performance engineering thermoplastic. Continuous service to 250 C. Excellent chemical resistance. For aerospace, medical implants and semiconductor equipment.

Engineering Plastics High-Performance Polymer ISOPEEK (ISO 13588) ENEN ISO 13588 ASTMD6262 / F2026 (medical PEEK) Trade NamesVICTREX PEEK (VICTREX) / Ketron PEEK (Quadrant) / Solvay KetaSpire / Evonik VESTAKEEP +24
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Description

PEEK (Polyether Ether Ketone) per ISO 13588 is a semi-crystalline high-performance thermoplastic with the highest continuous service temperature of commercial melt-processable polymers (250 C). Outstanding combination of mechanical strength (100 MPa), stiffness (3.6 GPa), excellent chemical resistance, biocompatibility and radiation resistance. Cost is 30-50x PA6 — justified only for extreme applications. Standard material for aerospace structural plastics, semiconductor equipment, medical implants and downhole oil tools.

Key Properties — Unfilled PEEK (standard)
Rm (Tensile Strength)
95 – 105
MPa
Re / Rp0.2 (Yield)
90 – 100
MPa
A₅ (Elongation)
≥ 30.0
%
E (Young's Modulus)
4
GPa
Density
1.32
g/cm³
Main Designations (28)
Standard BodyDesignationCountry / RegionNote
ISO PEEK (ISO 13588) International
EN EN ISO 13588 European Union
ASTM D6262 / F2026 (medical PEEK) USA
Trade Names VICTREX PEEK (VICTREX) / Ketron PEEK (Quadrant) / Solvay KetaSpire / Evonik VESTAKEEP Global
Medical Grade ASTM F2026 — surgical implants USA
Medical Grade ISO 10993 — biocompatibility International
UL 94 V-0 (excellent inherent flame retardance) USA
JIS PEEK (JIS K 7209) Japan
GOST PEEK (adopted designation) Russia / CIS
FDA Biocompatible grades per ISO 10993 (medical applications) USA
JUS PL-PEEK Yugoslavia / Serbia Polyether ether ketone high-performance polymer
Key Grades Unfilled PEEK / PEEK GF30 / PEEK CF30 (carbon fibre) / PEEK bearing grade Global
RoHS Compliant EU
Supply Forms Rod, sheet, tube (stock shapes) + injection moulding compound + coating powder Global
ISO PEEK (ISO 13588) International
EN EN ISO 13588 European Union
ASTM D6262 / F2026 (medical PEEK) USA
Trade Names VICTREX PEEK (VICTREX) / Ketron PEEK (Quadrant) / Solvay KetaSpire / Evonik VESTAKEEP Global
Medical Grade ASTM F2026 — surgical implants USA
Medical Grade ISO 10993 — biocompatibility International
UL 94 V-0 (excellent inherent flame retardance) USA
JIS PEEK (JIS K 7209) Japan
GOST PEEK (adopted designation) Russia / CIS
FDA Biocompatible grades per ISO 10993 USA
JUS PL-PEEK Yugoslavia / Serbia Polyether ether ketone high-performance polymer
Key Grades Unfilled PEEK / PEEK GF30 / PEEK CF30 / PEEK bearing grade Global
RoHS Compliant EU
Supply Forms Rod, sheet, tube (stock shapes) + injection moulding compound + coating powder Global
Standards (28)
#Standard BodyDesignationCountry / RegionNote
1 ISO PEEK (ISO 13588) International —
2 EN EN ISO 13588 European Union —
3 ASTM D6262 / F2026 (medical PEEK) USA —
4 Trade Names VICTREX PEEK (VICTREX) / Ketron PEEK (Quadrant) / Solvay KetaSpire / Evonik VESTAKEEP Global —
5 Medical Grade ASTM F2026 — surgical implants USA —
6 Medical Grade ISO 10993 — biocompatibility International —
7 UL 94 V-0 (excellent inherent flame retardance) USA —
8 JIS PEEK (JIS K 7209) Japan —
9 GOST PEEK (adopted designation) Russia / CIS —
10 FDA Biocompatible grades per ISO 10993 (medical applications) USA —
11 JUS PL-PEEK Yugoslavia / Serbia Polyether ether ketone high-performance polymer
12 Key Grades Unfilled PEEK / PEEK GF30 / PEEK CF30 (carbon fibre) / PEEK bearing grade Global —
13 RoHS Compliant EU —
14 Supply Forms Rod, sheet, tube (stock shapes) + injection moulding compound + coating powder Global —
15 ISO PEEK (ISO 13588) International —
16 EN EN ISO 13588 European Union —
17 ASTM D6262 / F2026 (medical PEEK) USA —
18 Trade Names VICTREX PEEK (VICTREX) / Ketron PEEK (Quadrant) / Solvay KetaSpire / Evonik VESTAKEEP Global —
19 Medical Grade ASTM F2026 — surgical implants USA —
20 Medical Grade ISO 10993 — biocompatibility International —
21 UL 94 V-0 (excellent inherent flame retardance) USA —
22 JIS PEEK (JIS K 7209) Japan —
23 GOST PEEK (adopted designation) Russia / CIS —
24 FDA Biocompatible grades per ISO 10993 USA —
25 JUS PL-PEEK Yugoslavia / Serbia Polyether ether ketone high-performance polymer
26 Key Grades Unfilled PEEK / PEEK GF30 / PEEK CF30 / PEEK bearing grade Global —
27 RoHS Compliant EU —
28 Supply Forms Rod, sheet, tube (stock shapes) + injection moulding compound + coating powder Global —
All values in wt.%
C
Carbon (aromatic ketone ether backbone)
~75.9000
H
Hydrogen
~5.5000
O
Oxygen (ether and ketone linkages)
~18.6000
H2O
Water absorption (equilibrium 50% RH)
≤ 0.5000
H2O
Water absorption (saturation)
≤ 0.5000
C
Carbon (aromatic ketone ether backbone)
~75.9000
H
Hydrogen
~5.5000
O
Oxygen (ether and ketone linkages)
~18.6000
H2O
Water absorption (equilibrium 50% RH)
≤ 0.5000
ElementSymbolMin %Max %Typical %
Carbon (aromatic ketone ether backbone) C — — 75.9000
Hydrogen H — — 5.5000
Oxygen (ether and ketone linkages) O — — 18.6000
Water absorption (equilibrium 50% RH) H2O — 0.5000 —
Water absorption (saturation) H2O — 0.5000 —
Carbon (aromatic ketone ether backbone) C — — 75.9000
Hydrogen H — — 5.5000
Oxygen (ether and ketone linkages) O — — 18.6000
Water absorption (equilibrium 50% RH) H2O — 0.5000 —
Mechanical Properties
ConditionCode Rm min
MPa		Rm max
MPa		 Re min
MPa		Re max
MPa		 A₅ min
%		 Z
%		 KV
J		 HB minHB max HRC minHRC max E
GPa
Unfilled PEEK (standard) STD 95 105 90 100 30.0 — — — — — — 3.6
PEEK GF30 (30% glass fibre) GF30 150 180 130 160 2.0 — — — — — — 11.0
PEEK CF30 (30% carbon fibre) CF30 170 200 150 180 1.0 — — — — — — 18.0
PEEK + PTFE + graphite (bearing) BRG 90 100 85 95 20.0 — — — — — — 3.5
Unfilled PEEK (standard) STD 95 105 90 100 30.0 — — — — — — 3.6
PEEK GF30 (30% glass fibre) GF30 150 180 130 160 2.0 — — — — — — 11.0
PEEK CF30 (30% carbon fibre) CF30 170 200 150 180 1.0 — — — — — — 18.0
PEEK + PTFE + graphite (bearing) BRG 90 100 85 95 20.0 — — — — — — 3.5
Physical Properties
Density
1.320
g/cm³
Melting Point
340–350
°C
Young's Modulus
3.6
GPa
Poisson's Ratio
0.380
—
Thermal Conductivity
0.3
W/m·K
Thermal Expansion
47.00
×10⁻⁶ /K
Specific Heat
1,340
J/kg·K
Magnetic
No
 
Heat Treatment
Drying (mandatory)
Temperature:150°C – 165°C
Medium:Circulating air oven (vacuum preferred)
Duration:4-6 h (moulding); 12-24h for stock shapes
Cooling:Sealed bag
Hardness After:Moisture <0.02%
MANDATORY before injection moulding. PEEK stock shapes also benefit from drying. High Tg requires elevated oven temperature.
Annealing (moulded/machined parts)
Temperature:200°C – 220°C
Medium:Circulating air oven
Duration:1-4 h
Cooling:Slow cool at 2 C/min
Hardness After:Crystallinity ~30-35%
STRONGLY recommended for precision parts. Increases crystallinity, reduces residual stress, stabilises dimensions. Critical for high-temperature applications.
Sterilisation (medical)
Temperature:121°C – 134°C
Medium:Autoclave (steam) — multiple cycles
Duration:20 min
Cooling:Cool slowly
Hardness After:No degradation after 1000+ cycles
Outstanding steam sterilisation resistance — one of the main advantages for medical applications. Also gamma and e-beam compatible.
Drying (mandatory)
Temperature:150°C – 165°C
Medium:Circulating air oven (vacuum preferred)
Duration:4-6 h
Cooling:Sealed bag
Hardness After:Moisture <0.02%
MANDATORY. High Tg requires elevated oven temperature.
Annealing (moulded/machined parts)
Temperature:200°C – 220°C
Medium:Circulating air oven
Duration:1-4 h
Cooling:Slow cool at 2 C/min
Hardness After:Crystallinity ~30-35%
STRONGLY recommended for precision parts. Increases crystallinity, reduces residual stress.
Sterilisation (medical)
Temperature:121°C – 134°C
Medium:Autoclave (steam) — multiple cycles
Duration:20 min
Cooling:Cool slowly
Hardness After:No degradation after 1000+ cycles
Outstanding steam sterilisation resistance — main advantage for medical applications.
Machinability
Machinability Rating
relative to AISI B1112 = 100%
150.0%
Good
Turning Speed (HSS)
400
m/min
Turning Speed (Carbide)
1,200
m/min
Feed Rate (Turning)
0.350
mm/rev
Drilling Speed (HSS)
300
m/min
Milling Speed (Carbide)
1,200
m/min
CoolantDry cutting or light MQL
Chip FormationShort-medium chips; good chip control; clean machining
Tool MaterialCarbide K10 (uncoated); PCD for CF30/GF30; sharp edge
Surface FinishRa 0.2-0.8 um achievable
Good machinability in unfilled grade. CF30 and GF30 grades are highly abrasive — PCD or carbide only.
Applications
Aerospace
Structural aircraft components (replacing aluminium), pump housings, valve bodies and fluid system components.
Medical Implants
Spinal cages/interbody fusion devices, craniofacial implants and bone plates — MRI-compatible.
Semiconductor
Wafer handling fixtures, process chamber components, robot end-effectors and valve bodies for ultra-pure media.
Oil & Gas
Downhole seals, valve seats, pump components and cable jacketing for high-temperature high-pressure wells.
Motorsport
High-performance engine components, pump bodies and structural brackets where weight vs service temperature is critical.
Aerospace
Structural aircraft components (replacing aluminium), pump housings and valve bodies.
Medical Implants
Spinal cages/interbody fusion devices, craniofacial implants and bone plates — MRI-compatible.
Semiconductor
Wafer handling fixtures, process chamber components and robot end-effectors.
Oil & Gas
Downhole seals, valve seats, pump components and cable jacketing for high-temperature wells.
Technical Notes
✅
PEEK vs Metals
PEEK offers strength comparable to aluminium alloys (6082-T6) with 40% weight saving and outstanding chemical and electrical resistance. At 250 C service temperature, PEEK outperforms all standard engineering plastics. Where PEEK is suitable, it eliminates corrosion, reduces weight and can be manufactured in complex shapes.
⚠️
High Cost
PEEK is 30-50x the cost of PA6 or POM. Evaluate whether a lower-cost polymer (PEI, PPSU, PPS) meets requirements before specifying PEEK. PEEK is only justified for extreme temperature, chemical or biomedical demands.
💧
Chemical Resistance
Outstanding — superior to all standard engineering plastics. Resistant to: virtually all organic solvents, acids (concentrated H2SO4 and HNO3 attack slowly), bases and halogens. NOT resistant to: concentrated sulfuric acid (>96%), some chlorinated solvents at high temperature and oxidising halogen agents.
✅
MRI Compatibility
PEEK is non-conductive, non-magnetic and produces no MRI artifacts — making it the preferred metal-replacement material for spinal implants and surgical instruments used in MRI-guided procedures.
✅
PEEK vs Metals
PEEK offers strength comparable to 6082 aluminium with 40% weight saving and outstanding chemical and electrical resistance. At 250 C service temperature, PEEK outperforms all standard engineering plastics.
⚠️
High Cost
PEEK is 30-50x the cost of PA6 or POM. Evaluate whether a lower-cost polymer (PEI, PPSU, PPS) meets requirements before specifying PEEK.
💧
Chemical Resistance
Outstanding — superior to all standard engineering plastics. Resistant to: virtually all organic solvents, acids, bases and halogens. NOT resistant to: concentrated sulfuric acid (>96%) and some chlorinated solvents at high temperature.
✅
MRI Compatibility
PEEK is non-conductive, non-magnetic and produces no MRI artifacts — preferred for spinal implants and surgical instruments used in MRI-guided procedures.