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Model No: 18Ni300
18Ni300 Maraging Steel
18Ni300 maraging steel features ultra-high strength and good toughness, along with excellent welding and polishing properties.
Quantity :
Product Introduction
18Ni300 is a carbon-free (or ultra-low carbon) maraging steel. It does not rely on carbides but rather on precipitation hardening via intermetallic compounds—in other words, its hardness is"grown"rather than achieved through quenching. Maraging steel 300 provides the world's highest-quality fencing blades.
In its solution-annealed state, Maraging Steel 300 has a hardness of only around HRC 30, making its machinability—including turning, milling, drilling, and grinding—comparable to that of ordinary alloy steels. After machining is complete, the material undergoes aging at 480°C, raising its hardness to HRC 50–54 while its dimensions remain virtually unchanged (with a shrinkage rate of less than 0.05%).
It is precisely this characteristic that accounts for its high cost; as our Lork engineers put it, the value of this material lies in its processing capabilities.
Who needs it?
- Do you need to produce high-gloss, mirror-finish plastic molds that are free of pinholes after polishing?
- Do you run glass-fiber reinforced materials in your injection molds, causing standard mold steels to wear out after just tens of thousands of cycles?
- Do you require aerospace structural components with a tensile strength exceeding 2000 MPa that are also weldable?
- Do you need precision tooling that maintains dimensional stability under high loads without loosening during operation?
The 18Ni300 supplied by Lork Group strictly complies with AMS 6514 / ASTM A538 standards and comes with a complete Certified Material Test Report (CMTR), covering chemical composition, mechanical properties, ultrasonic testing results, and grain size ratings.
Lork Group holds ISO 9001, AS9100D, and CE certifications. The company can also provide third-party inspection reports (SGS/BV) upon request.
Chemical Composition
Typical chemical composition ranges supplied by Lork Group (compliant with ASTM A538 / AMS 6514)
| Material Type | C | P | S | Mn | Ai | Ni | Cr | Co | Mo | Ti | Fe |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Content (wt%) | ≤ 0.03 | ≤ 0.01 | ≤ 0.01 | ≤ 0.10 | 0.05 - 0.15 | 17.0 - 19.0 | 2.60-3.00 | 8.0 - 9.5 | 4.5 - 5.2 | 0.5 - 0.8 | Balance |
Mechanical properties: Solution-treated state vs. aged state—a vast difference.
18Ni300 has two"faces"—it looks one way when purchased and another when in use.
🔹 Solution-annealed state (delivery condition, non-aged)
Hardness: HRC 28–35 (typical values approx. HRC 30–34)
Hardness: HRC 28–35 (typical values approx. HRC 30–34)
Tensile strength: Approx. 1100–1200 MPa (experimentally measured value in as-printed state: 1174 MPa)
Elongation: Approx. 12% (good ductility in the solution-annealed state; easy to machine)
Characteristics: Soft and easy to machine. Suitable for turning, milling, drilling, and grinding; machining feel is similar to that of ordinary alloy steel.
🔹 Aged condition (after aging at 480–490°C)
| Performance indicators | Tensile Strength | Yield Strength | Elongation | Hardness | Fracture toughness (KIC) |
|---|---|---|---|---|---|
| Typical value | 2000 - 2127 MPa | 1900 - 2093 MPa | 4 - 7% | HRC 50 - 54 | ≥ 80 MPa·m¹/² |
Testing and Delivery: How Lork Group Ensures Quality
Lork Group Standard Testing Items:
1. Chemical Composition (PMI): Spectroscopic analysis per batch. Key focus on verifying Ni, Co, Mo, and Ti content; carbon content ≤0.03% is the baseline requirement.
2.Mechanical Properties: Tensile testing (tensile strength, yield strength, elongation), hardness (tested in both solution-annealed and aged conditions), and impact energy (Charpy V-notch).
3.Ultrasonic Testing (UT): Per AMS 2631 standard; sensitivity equivalent to a ≤0.5 mm flat-bottom hole. Used to detect internal segregation, voids, and inclusions.
4.Grain Size Rating: Per ASTM E112; requirement is Grade 7 or finer. A fine-grained microstructure is the foundation for high performance.
5.Dimensions and Appearance:
- Round Bar Tolerance: h6, h7, or h8 (selectable)
- Surface Finish: Black bar, peeled, or polished (selectable)
- Straightness: ≤0.5 mm/m (tighter tolerances available upon request)
Optional Value-Added Services:
- Precision Centerless Grinding: Diameter tolerance up to ±0.01mm; surface roughness Ra ≤ 0.8μm
- Fixed-Length Cutting: Length tolerance ±1mm
- Stress-Relief Treatment: Stress-relief annealing performed after precision rolling or precision turning to ensure flatness
- Third-Party Inspection: Inspection reports can be issued by SGS or BV
Pricing and Lead Times
The price of 18Ni300 is significantly influenced by market fluctuations in nickel and cobalt. Price quotes from Lork Group are valid for 7 days.
Reference price range (based on 2026 market conditions; solution-annealed bars):
- Bulk orders (≥500 kg): Approx. 120–160 CNY/kg
- Small-batch samples: Unit price 15–20% higher
Estimated lead times:
- Standard stock items: 3–7 working days
- Non-standard sizes / Custom forgings: 3–5 weeks
- Age-hardened condition: Add 3–5 days to the lead time for solution-annealed material
Contact the Lork Group technical team
Buying the wrong condition of 18Ni300 is a waste of money. Send us your application, dimensions, and heat treatment requirements, and our materials engineers will assist you with material selection and process matching—free of charge.
Email:daisy@lorkgroup.com
WhatsApp: +86 175 1308 1871
