PEEK is usually not the first plastic considered on a new program. It becomes relevant when the application environment is harsh enough that lower-cost plastics will not hold up over time. That is why it appears in medical devices, aerospace-adjacent hardware, advanced automation, and chemically demanding assemblies.
For buyers, the most practical question is whether PEEK is functionally necessary. If the part truly needs its heat resistance, chemical resistance, or stronger mechanical stability, PEEK can be worth the premium. If not, a lower-cost engineering plastic may be the better sourcing decision.
PEEK stock shapes cost roughly 10–20× more than nylon or acetal by volume, and machining speeds are typically slower to preserve surface quality. However, with a continuous service temperature of ~250 °C and tensile strength around 100 MPa (unfilled), PEEK outperforms most engineering plastics by a wide margin. It is also inherently flame-retardant (UL 94 V-0) and resistant to steam, gamma radiation, and most organic solvents — properties that make it effectively irreplaceable in certain medical, aerospace, and semiconductor applications.
