Engineering plastic · ISO 10350

PEEK (Unfilled) — Machining & Properties

Typical properties, what PEEK (Unfilled) is like on a machine tool, what it gets used for, and the tolerance and finishes we hold on it — from a shop that actually machines it, not a datasheet aggregator. Every figure here drives our own calculators.

1.32 g/cm³
Density (typical)
100 MPa
Tensile strength
M99
Hardness
Good
Machinability
47 µm/m·°C
Thermal expansion
±0.020mm
Achievable tolerance

Machining PEEK (Unfilled)

Machinability is rated good — a well-behaved material to machine with correctly chosen tooling and parameters. Engineering polymers have significantly higher thermal expansion coefficients than metals. All plastic components must be inspected at a controlled temperature, and tolerances tighter than ±0.020 mm are generally not maintainable in service without dimensional constraints in the design.

Our standard achievable tolerance on PEEK (Unfilled) is ±0.020mm under normal conditions, with tighter tolerances on critical features agreed at quotation. Standard finishes: Autoclave-sterilisable; biocompatible. Full material traceability with MTR and CoC documentation on every order.

Typical applications

Medical sterilisable components, semiconductor insulators, bearing cages.

Use PEEK (Unfilled) in our free tools

Other engineering plastic grades we machine: PEEK-CF30 · Delrin POM-C · Delrin POM-H · Nylon PA6all 50 grades.

Reference tool. Values are typical for the grade and condition stated and vary by supplier, temper and batch — they are reference data, not a specification. The Material Test Report supplied with your order is the governing document for the material actually used. Figures are provided in good faith for early design guidance and are not a substitute for the published standard or your own engineering judgement. Always verify against the controlled standard and your drawing before manufacture. If a feature is critical, tell us at quotation stage and we'll confirm it explicitly.
Questions engineers actually ask

PEEK (Unfilled) — FAQ

What is the density of PEEK (Unfilled)?

1.32 g/cm³ (typical). That is 1320 kg/m³ — our metal weight calculator uses exactly this figure for PEEK (Unfilled).

What is the tensile strength of PEEK (Unfilled)?

Typically 100 MPa. Treat it as a typical value, not a specification — the Material Test Report supplied with your order states the actual certified figures for the batch.

Is PEEK (Unfilled) easy to machine?

Its machinability is rated good — a well-behaved material to machine with correctly chosen tooling and parameters.

What is PEEK (Unfilled) used for?

Typical applications: Medical sterilisable components, semiconductor insulators, bearing cages.

What tolerance can be held when machining PEEK (Unfilled)?

Our standard achievable tolerance on PEEK (Unfilled) is ±0.020mm under normal conditions (ISO 2768-f general tolerancing). Tighter tolerances on critical features can be agreed at quotation for specific geometries.

Can Dalloway machine PEEK (Unfilled)?

Yes — we machine PEEK (Unfilled) in-house on 3, 4 and 5-axis milling and CNC turning, from single prototypes to production, with MTR and CoC documentation standard. Typical finishes: Autoclave-sterilisable; biocompatible.

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