NAK55 Pre-hardened Plastic Mold Steel – Excellent Machinability & Polishing Performance

• Pre-hardened (HRC 37–43), ready to use without heat treatment

• Excellent machinability and EDM performance

• High dimensional stability after processing

• Superior polishing and photo-etching properties

• Good weldability and nitriding response

• Ideal for high-gloss plastic parts and mirror surface molds

NAK55 Tool Steel – Premium Pre-Hardened Steel for High-Precision Plastic Molds

NAK55 is a pre-hardened plastic mold steel widely used in high-precision injection molds. With hardness ranging from HRC 37–43, it is delivered ready to use and offers excellent machinability, polishing performance, and dimensional stability. Its fine microstructure makes it ideal for molds requiring mirror finishes and tight tolerances.

Chemical Composition (%):

Typical Applications:

• Plastic injection mold bases and inserts

• High-gloss and transparent product molds

• Consumer electronics and automotive molds

• Photo-etched and engraved mold components

• Suitable for mirror polishing and EDM

Delivery Condition:

• Pre-hardened to HRC 37–43

• Available in flat bars, round bars, and blocks

• Machined or forged surface

Available Sizes:

• Round bar: Ø20mm – Ø300mm

• Flat bar: Thickness 10–300mm, Width up to 800mm

• Custom dimensions and machining available

• MOQ: 10 KG

• Lead Time: 3–7 working days

• Packing: Plastic film + steel belt + wooden pallet/crate

• Shipping: Global delivery by sea, air, or courier

• Support: Mill Test Certificate (MTC), Third-party inspection available

• Service: Sample cutting, surface machining, technical guidance