NiMark® 300/M300

UNS #K93120

NiMark® 300 is a low-carbon, nickel-cobalt-molybdenum high-temperature alloy capable of attaining yield strengths in excess of 270 ksi (1862 MPa) through simple, low temperature heat treatment at 900°F (482°C). It exhibits good ductility at high strength levels, excellent notch ductility, and is readily welded. NiMark® 300 is one of a family of "maraging" nickel steels which is martensitic yet ductile in the solution treated condition and attains ultra-high strength through a single low temperature aging treatment.

Type Analysis

  • Carbon (Maximum) 0.03
  • Phosphorus (Maximum) 0.01
  • Silicon (Maximum) 0.1
  • Nickel (Nominal) 18.5
  • Titanium (Nominal) 0.65
  • Manganese (Maximum) 0.1
  • Sulfur (Maximum) 0.01
  • Cobalt (Nominal) 8.75
  • Molybdenum (Nominal) 4.9
  • Iron (Nominal) Balance
  • Calcium (Nominal) 0.05
  • Aluminum (Nominal) 0.1
  • Boron (Nominal) 0.003
  • Zirconium (Nominal) 0.03


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Applicable Specifications

  • AMS 64514
  • MIL-S-46850





Weld Wire


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