Alleima® 20C is a hardened and tempered carbon steel characterized by: - High strength - High fatigue strength under bending and impact stress - Low level of non-metallic inclusions - Good wear resistance Compressor valve steel in Alleima® 20C has excellent surface finish, good dimensional tolerances and good flatness. Chemical composition (nominal) Chemical composition (nominal) % Applications Valve production Valves made from Alleima® 20C compressor valve steel should be produced with fatigue properties in mind, in order to make full use of the excellent material properties. Valve types: - Flapper valves - Reed valves - Check valves Forms of supply Datasheet last updated 5/9/2025 6:38:02 AM (supersedes all previous editions) 1 ALLEIMA® 20C COMPRESSOR VALVE STEEL

Strip steel is supplied in labelled coils, or on labelled 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. Coils are wrapped in paper and packed in wooden cases. For overseas shipment, coils are also sealed in a plastic bag containing silica gel. Net and gross weights are marked on the case. Customized properties, dimensions and tolerances can be supplied on request. Thickness Alleima® 20C comprevalve steel is supplied in standard thicknesses...

Surface roughness Maximum surface roughness values, cut-off 0.25 mm (.0098 inch), are shown in the table. Surface defects 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 in.) and 3 pm (120 pin.) maximum for thicker material. The maximum scratch depth allowed is as follows: Out-of-straightness is defined as the maximum deviation from a straight-edge of a specified length. The following values apply: Datasheet last updated 5/9/2025 6:38:02 AM (supersedes all previous editions) 3 ALLEIMA®...

The proof strength (Rp0.2) is approximately 90% of the tensile strength (Rm). The manufacturing tolerance for tensile strength is ±80 MPa (±11.6 ksi.) Fatigue strength Alleima® 20C compressor valve steel has been used in the compressor industry for many years. The steel is tailored for applications requiring high fatigue strength. The fatigue strength depends on the surface and edge treatment of the material. The values presented are from none tumbled material with a smooth edge. Reversed bending fatigue (mean stress = 0) Figure 1. Reversed bending fatigue strength at a failure rate of 5%, as...

Thermal conductivity Specific heat capacity Mean value for 120-210°F, Btu/(lb °F) 0.11 Thermal expansion, mean values in temperature ranges (x 10-6) Temperature Temperature Modulus of elasticity, static properties at 20°C (68°F) Datasheet last updated 5/9/2025 6:38:02 AM (supersedes all previous editions) 5 ALLEIMA® 20C COMPRESSOR VALVE STEEL

alleima.com/contact-us ALLEIMA.COM Datasheet last updated 5/9/2025 6:38:02 AM (supersedes all previous editions) Recommendations are for guidance only, and the suitability of a material for a specific application can be confirmed only when we know the actual service conditions. Continuous development may necessitate changes in technical data without notice. This datasheet is only valid for Alleima materials