PEEK Machined Components and Suppliers in Fond du Lac, WI

Unfilled PEEK in its natural (off-white to tan) form delivers the polymer's intrinsic properties without modification: tensile strength of 100 MPa, flexural modulus of 3.6 GPa, continuous service temperature of 250 degrees Celsius, and a coefficient of friction against steel of approximately 0.35 in dry sliding contact. These numbers position unfilled PEEK above most engineering thermoplastics (nylon, Delrin, UHMWPE) in demanding thermal and chemical environments. For Fond du Lac's marine and industrial applications, unfilled PEEK is specified for seal rings, backup rings in hydraulic systems, and electrical insulation bushings where the combination of temperature resistance and chemical inertness eliminates the degradation failures seen with lesser polymers. Machining unfilled PEEK requires attention to tool geometry and cutting conditions to prevent the surface delamination and stress cracking that can occur with incorrect parameters. Sharp, positive-rake carbide tooling at moderate speeds (400 to 600 SFM) with light feeds (0.002 to 0.005 inch per revolution) produces clean, burr-free surfaces with Ra values of 32 to 63 microinch in turning. Drilling PEEK requires peck-drill cycles with adequate chip evacuation to prevent heat buildup — PEEK's glass transition temperature of 143 degrees Celsius means that localized frictional heating can soften the material at the drill tip, closing the hole and breaking the drill. Fond du Lac shops experienced with high-performance polymer machining use through-coolant or mist cooling for PEEK drilling operations deeper than 3 diameters. Dimensional stability is a key advantage of unfilled PEEK over nylon and acetal in precision applications. PEEK's moisture absorption is less than 0.1 percent (versus 1.5 to 3 percent for nylon 6/6), meaning that bore diameters and bearing fits established at machining remain stable in humid or immersed environments. This makes unfilled PEEK the preferred bearing liner material for Fond du Lac's wet-environment applications — pump impeller wear rings, water-cooled bearing housings, and marine drive shaft bushings where nylon's dimensional shift under water absorption would create clearance problems.

Glass-filled PEEK (30 percent glass fiber by weight is the most common formulation) substantially increases stiffness and reduces creep at elevated temperatures, raising the flexural modulus from 3.6 GPa to approximately 10 GPa and the tensile strength from 100 MPa to 160 MPa. For Fond du Lac's structural and mechanical applications — load-bearing brackets, seal carriers in hydraulic cylinders, and guide rails under continuous compressive load — glass-filled PEEK provides a cost-effective upgrade over unfilled PEEK when deflection or creep under sustained load is the governing design constraint. The 30 percent glass fiber formulation also reduces the coefficient of thermal expansion from 47 micrometers per meter per degree Celsius (unfilled) to approximately 20, which is important for assemblies that span a wide service temperature range and must maintain tight clearances. Carbon-filled PEEK (30 percent carbon fiber) takes a different performance path: it maximizes stiffness (flexural modulus to 14 GPa), improves thermal conductivity, and dramatically reduces the coefficient of friction and wear rate in sliding contact applications. The carbon fiber filler acts as a solid lubricant in the bearing matrix, reducing the coefficient of friction against steel to approximately 0.10 to 0.15 in dry sliding — compared to 0.35 for unfilled PEEK. For thrust washers, journal bearings, and wear pads in Fond du Lac's equipment supply chain, carbon-filled PEEK running against hardened steel or chrome surfaces can achieve PV (pressure times velocity) limits above 10,000 psi-ft/min without lubricant, enabling dry-running designs that reduce maintenance requirements in hard-to-access equipment locations. Machining filled grades requires modified parameters relative to unfilled PEEK. Glass and carbon fibers are abrasive to cutting tools, demanding PCD (polycrystalline diamond) tooling for production volumes or at minimum CVD diamond-coated carbide for medium runs. Tool wear rates with standard uncoated carbide tooling on 30 percent carbon-filled PEEK are 5 to 10 times higher than on unfilled PEEK, which affects tooling cost per part calculations significantly. Fond du Lac shops quoting filled PEEK components should identify the filler type and content at the RFQ stage to correctly estimate tooling life and overall part cost.

PEEK's chemical resistance profile is one of its most compelling attributes for Fond du Lac's marine and industrial applications. It resists virtually all organic solvents, fuels, hydraulic fluids, and mineral acids at room temperature, and maintains structural integrity in steam and hot water to 150 degrees Celsius. For Mercury Marine's outboard and sterndrive applications, PEEK components in fuel system assemblies, cooling water circuits, and electrical isolation roles perform without the swelling, softening, or stress cracking that would compromise nylon or acetal parts in the same environments. The polymer is FDA-compliant in its unfilled form, which opens additional applications in food-processing equipment — a secondary market for some Fond du Lac industrial manufacturers. Thermal management is the primary design consideration when integrating PEEK into assemblies with metal components. PEEK's thermal conductivity is low (0.25 W/m-K unfilled, rising to 1.0 W/m-K with carbon fill) compared to aluminum (160 W/m-K) or steel (50 W/m-K), meaning that PEEK components in heat-generating assemblies must be sized to conduct heat through their cross-section or rely on convective cooling at their exposed surfaces. For bearing applications, this drives designers toward thin-section ring designs with maximum surface area rather than solid cylindrical bushings. Carbon-filled PEEK's improved thermal conductivity (relative to unfilled) is a meaningful advantage in bearing applications where heat dissipation from the sliding contact zone determines maximum operating speed. Prototyping PEEK is straightforward through Fond du Lac's regional machining shops: PEEK rod and plate stock is available from regional plastics distributors in diameters from 0.250 inch to 8 inch and thicknesses from 0.125 inch to 4 inch. First-article turnaround for a machined PEEK prototype is typically 5 to 10 business days, allowing rapid design iteration before committing to injection mold tooling for higher-volume production.