Datasheet updated

2024-01-11 10:32
(supersedes all previous editions)

Alleima® High-N is a molybdenum and nitrogen alloyed austenitic stainless steel, used for orthopedic implants and fracture fixation devices.

The grade is characterized by:

  • Proof strength is up to twice that of Alleima® 316LVM in the annealed condition
  • Higher corrosion resistance than Alleima® 316LVM
  • High microcleanliness
  • Very good surface finish
  • Good forgeability


  • UNS: S31675
  • BS: 7252-9

Product standard

  • ASTM F1586

Chemical composition (nominal)

Chemical composition (nominal) %
C Si Mn P S Cr Ni Mo Cu N Nb
≤0.06 ≤0.60 4.0 ≤0.025 ≤0.003 20.5 9.5 2.4 ≤0.20 0.4 0.3


Alleima® High-N grade is used for hip and knee joints and fracture fixation devices.

Corrosion resistance

Alleima® High-N has a very good resistance in physiological environments to:

  • General and intergranular corrosion due to high purity and low ferrite content
  • Pitting and crevice corrosion due to the high molybdenum content

Alleima® High-N is capable of passing the Moneypenny Strauss corrosion test in accordance with ISO / ASTM requirements.

Forms of supply


  • Bright annealed
  • Cold finished
  • Ground outside surface


The tolerances for OD and ID, excentricity and straightness are determined in accordance with customers' requirements.

Alleima standard: OD and ID ± 0.04 mm (0.0016 in.); excentricity max. 5%

Other product forms

Alleima High-N can also be supplied as bar.

Mechanical properties

Product Condition Tensile strength Proof strength Elongation A,
Rm Rp0,2 %
MPa ksi MPa ksi
min min min min typical
Wire 1500 max 217 max
Bar Annealed 740 107 430 62 35
Bar Medium 1000 145 700 102 20
Bar Hard 1100 160 1000 145 10
Tube, thick wall Bright annealed 740 107 430 62 min 35
Tube, thick wall Cold finished 1200 174 1100 160 min 10

Specific tensile requirements available on request

Physical properties

Density ( 20 °C) 8.0 g/cm3 0.29 lb/in3
Modulus of elasticity, x103 (20°C) 200 MPa 29.0ksi
Specific heat capacity (20°C) 485 J/(kg °C) 0.11Btu/(lb°F)
Thermal conductivity (20°C) 14W /(m°C) 8 Btu/(ft h °F)
Thermal expansion, x10-6 (30-100°C) 16.5 per °C 9.5 per °F


Hardness Cutting speed range Feed range
SFM m/min IPR mm/rev
Turning 250-400 885-145 270-45 0.002-0.024 0.05-0.6
Milling 250-400 855-245 260-75 0.002-0.016 0.05-0.4
Drilling 250-400 115-195 35-60 0.002-0.012 0.05-0.3

Disclaimer: Alleima is not providing any products or services that are intended or may be construed to be recommending or otherwise advising on, in any manner, the design, suitability, appropriateness or effectiveness, from a medical/biological/safety perspective, of any medical material, instrument and/or medical device.