Maraging Steel (18Ni-300 / 1.2709)
An ultra-high-strength tool steel achieving 2,000+ MPa tensile strength after aging. Maraging steel is the standard AM material for injection mould tooling with conformal cooling, die casting inserts, and high-performance mechanical components.
About Maraging Steel (18Ni-300 / 1.2709)
Maraging steel (grade 300 / 1.2709) is a nickel-cobalt-molybdenum alloy that achieves its exceptional hardness (50–56 HRC) through age hardening at relatively low temperature (~490 °C). Unlike conventional tool steels, it does not require quenching — the aging process produces minimal dimensional change, making it ideal for precision tooling.
In AM, maraging steel is predominantly used for injection mould inserts with conformal cooling channels. These AM-specific cooling geometries can reduce cycle times by 20–40% compared to conventionally drilled cooling lines — a direct return on investment that has made this one of the most commercially proven AM applications.
The material is also used for high-strength structural components, particularly in motorsport and aerospace where specific strength requirements exceed what titanium or steel alloys can provide.
Typical Applications
- Injection mould inserts with conformal cooling
- Die casting tooling
- Aerospace structural fittings
- Motorsport drivetrain components
- Precision fixtures and gauges
Engineering Considerations
- Very low ductility (3–5%) — not suitable for impact-loaded or dynamic applications
- Aging heat treatment is simple (single step at 490 °C) but essential for target hardness
- Not stainless — requires coating or surface treatment for corrosive environments
- Machining in aged condition requires HSS or carbide tooling