Freeflex® Core is a hardened and tempered martensitic stainless compressor valve steel alloyed with copper. The material is characterized by: - Excellent combination of high strength and high ductility - Extremely high fatigue strength under bending and impact stress - Excellent surface finish - Very high compressive residual surface stress - Low level of non-metallic inclusions - Very good wear resistance Freeflex® Core compressor valve steel has excellent dimensional tolerances and flatness. Chemical composition (nominal) Chemical composition (nominal) % ApplicationsValve types: - Flapper valves - Reed valves - Check valves FabricationTumbling A good tumbling operation giving a round, smooth edge is necessary in order to minimize stress concentrations. Tumbling also increases the residual compressive surface stresses which gives a significant further improvement in fatigue properties. Datasheet last updated 5/9/2025 6:38:02 AM (supersedes all previous editions)

FinishEdges Edges are slit and deburred. Shaved edges can be supplied on request. Maximum out-of-flatness across and along the strip is 0.20% of the nominal strip width. Maximum surface roughness values, cut-off 0.80 mm (0.031 in.), are shown in the table. A small number of surface defects, such as pits and roll marks, with a depth or height of 2 pm (80 pin.) maximum is allowed for thicknesses up to 0.508 mm (0.020 inch) and 3 pm (120 pin.) maximum for thicker material. The maximum scratch depth allowed is as follows: Straightness Out-of-straightness is defined as the maximum deviation from a...

Proof strength Tensile strength The values are valid for thicknesses up to 0.60 mm (0.024 inch). The manufacturing tolerance for tensile strength is ±60 MPa (±8.7 ksi). Freeflex® Core compressor valve steel has a high response to surface treatment, such as tumbling and shot peening, which gives a significant increase in fatigue life.Values below origin from samples in tumbled condition. The fatigue strength of Freeflex® Core compressor valve steel in reversed bending is ±1010 MPa (±146 ksi) at a failure rate of 5%. Fluctuating bending fatigue strength for Freeflex® Core has been calculated from...

Modulus of elasticity, static properties at 20°C (68°F) Datasheet last updated 5/9/2025 6:38:02 AM (supersedes all previous editions)

Forms of supply Conditions and forms of supply Strip steel is supplied in labeled coils, or on labeled plastic spools, depending on weight and size. The label details the steel grade, heat, lot and coil number, and nominal size, allowing full material traceability. Material is protected against rust with oil. Dimensions Thickness Freeflex® Core is supplied in standard thicknesses in accordance with the table. Customized thicknesses can be supplied on request. Tolerances Width Strip in standard thicknesses is stocked in widths up to 325 mm (12.8 in.), ready for slitting to the required width. Disclaimer:...