- 4817 E. 355th St Willoughby, OH 44094
- Info@AmericanSpecialtyMetals.com
- 440-951-7600
420SS mold steel is a martensitic stainless steel known for its excellent corrosion resistance, high polishability, and wear resistance. With a high carbon content and chromium composition, it provides an ideal balance between hardness and machinability, making it a preferred choice for plastic injection mold tooling and die components.
High Corrosion Resistance: Thanks to its 12–14% chromium content, 420SS offers strong resistance to moisture, mild acids, and plastic off-gassing, making it suitable for molds used in humid or corrosive environments.
Hardness & Wear Resistance: Can be hardened up to ~50 HRC, providing long tool life and resistance to abrasion.
Polishability: Its fine grain structure and corrosion resistance make it easy to achieve a mirror-like polish, ideal for transparent plastic mold applications.
Dimensional Stability: Maintains shape and tolerances during heat treatment, improving consistency in high-volume production.
420SS is readily machinable in the annealed condition and can be heat treated for enhanced hardness and durability. The steel responds well to hardening through oil or air quenching, followed by tempering to reduce brittleness. Post-machining polishing is straightforward, making it a go-to material for high-finish mold cavities.
Low Maintenance: Resists rusting and corrosion, reducing downtime for cleaning.
Longevity: High hardness ensures a longer mold life, especially in abrasive plastic applications.
Aesthetic Quality: Allows for fine detail and high-finish mold production, crucial for consumer-facing plastic components.
At American Specialty Metal, we are more than just a supplier — we are your trusted partner in precision steel solutions. Whether you’re in tool and die, metal stamping, or automotive manufacturing, we deliver cut-to-size steel tailored to your exact specifications. Here’s why leading industries across the country rely on us
From H-13 hot work steel to 420SS mold steel, we stock and source only premium-grade materials that meet industry standards for strength, polishability, wear resistance, and longevity.
At American Specialty Metal, you’ll always talk to a knowledgeable team member who understands your industry. We take pride in offering personalized support, competitive pricing, and long-term relationships.
440-951-7600
