Mold Steels (The most common category)
Carbon Structural Steel: Representative grade: 45 steel. Low cost; offers basic strength and toughness but poor hardenability; suitable only for simple, low-precision molds.
Pre-hardened Mold Steel:Representative grades: P20, 718H, P20+Ni. Pre-hardened to HRC 30–40 at the factory; allows for direct machining without subsequent heat treatment, avoiding deformation issues; widely used for small, medium, and large conventional plastic molds.
Alloy Structural Steel: Representative grade: 3Cr2Mo. Offers excellent comprehensive mechanical properties and high hardenability; a common choice for mid-to-low-end plastic molds.
Age-hardening Steel: Representative grade: 18Ni (250). Features excellent strength, hardness, toughness, and dimensional stability; properties are further enhanced through aging treatment; specifically suited for high-precision plastic molds.
Quenched Steel: Representative grades: H13, S136. Hardness reaches HRC 48–52 after heat treatment; offers superior wear resistance; suitable for high-precision molds requiring long service life and high-volume production.
Corrosion-resistant Steel: Representative grades: 420 stainless steel, 2316. Contains ≥13% chromium and resists acid/alkali corrosion; specifically used for processing plastics that release corrosive gases, such as PVC.
High-mirror-finish Mold Steel:Representative grade: NAK80. Capable of achieving a mirror-like surface finish (Ra ≤ 0.05 μm); meets production requirements for highly transparent plastic products and optical-grade components.
