Datasheet updated

2024-01-11 10:29
(supersedes all previous editions)

Sanmac® 329 is a duplex stainless steel with optimized sulfur content and inclusion morphology for improved machinability. The grade is characterized by:

  • Excellent machinability
  • High mechanical strength
  • Very good resistance to pitting and stress corrosion cracking


    • EN Number: 1.4460

    Product standard

    • EN 10088-3

    Chemical composition (nominal)

    Chemical composition (nominal) %
    C Si Mn P S Cr Ni Mo N
    ≤0.05 ≤1.0 ≤2.0 ≤0.035 ≤0.030 25.5 5 1.5 0.08


    Sanmac® 329 is especially suited for the manufacture of components for pumps and other equipment used in, for example, alkaline environments commonly found in the pulp and paper industry.

    Corrosion resistance

    Sanmac® 329 has a Pitting Resistance Equivalent (PRE*) of ≥31.

    *The PRE is defined as, in weight %:
    PRE = % Cr + 3.3 x % Mo +16 x % N

    Sanmac® 329 has very good resistance to stress corrosion cracking in chloride environments. The grade has also good resistance to general corrosion in acidic media, thanks to the high chromium content and alloying with molybdenum.

    Forms of supply


    Finishes and dimensions
    The standard size range for bar steel in Sanmac® 329 is 75-180 mm. Round bar is supplied in the solution annealed, quenched and peel-turned condition.

    Bars are delivered in random lengths of 3-7 m, depending on diameter.

    Diameter, mm Height of arch, mm/m
    Typical value
    > 75 2
    Diameter, mm Tolerances, mm
    75-95 -0/+1.00
    95-180 -0/+1.50
    Surface conditions
    Surface conditions Ra, µm
    Typical value
    Diameter, mm
    Peeled and burnished 1 75-180

    Mechanical properties

    At 20°C (68°F)

    Metric units
    Proof strengthTensile strengthElong.Hardness
    Rp0.2a)Rp1.0a) Ab)Brinell
    ≥450 620-880 20 ≤260
    Imperial units
    Proof strengthTensile strengthElong.Hardness
    Rp0.2a)Rp1.0a) Ab)Brinell
    ≥65 90-128 20 ≤260

    1 MPa = 1 N/mm2
    a) Rp0.2 and Rp1.0 correspond to 0.2% offset and 1.0% offset yield strength respectively.
    b) Based on L0 = 5.65√S, where L0 is the original gauge length and S0 the original cross-sectional area.

    Impact strength at room temperature

    ≥85 J

    Physical properties


    7.8 g/cm3, 0.28 lb/in3

    Specific heat capacity

    20°C: 500 J/(kg °C)
    68°F: 0.12 Btu/(lb °F)

    Thermal conductivity

    20°C: 15 W/(m °C)
    68°F: 9 Btu/(ft h °F)

    Thermal expansion, mean values in temperature ranges (X10-6)

    Metric units
    Temperature, °C 30-100 30-200 30-300
    Per °C
    Sanmac 329 13.0 13.5 14.0
    Carbon steel 12.5 13.0 13.5
    ASTM 316L 16.5 17.0 17.5
    Imperial units
    Temperature, °F 86-200 86-400 86-600
    Per °F
    Sanmac® 329 7.0 7.5 7.8
    Carbon steel 6.8 7.0 7.5
    ASTM 316L 9.0 9.5 9.8

    Sanmac® 329 has a far lower coefficient of thermal expansion than austenitic stainless steels and can therefore possess certain design advantages.


    20°C: 0.8 μΩm
    68°F: 31.5 μΩin.

    Modulus of elasticity (x103)
    Temperature, °C MPa Temperature, °F ksi
    20 200 68 29.0
    100 194 200 28.2
    200 186 400 27.0
    300 180 600 26.2


    Recommended inserts and cutting data starting values


    Insert geometry Grade Feed Cutting speed (m/min.)
    MF GC2015 0.15 210
    MM GC2025 0.30 190

    Thread turning

    Insert geometry Grade Cutting speed (m/min.)
    F GC1135 120

    Thread tapping

    Cutting speed (m/min.)
    4-12 Cutting speeds in the upper range should be chosen for coated threading taps.

    Parting off

    Insert geometry Grade Feed (mm/rev) Cutting speed (m/min.)
    CM GC1145 0.08-0.12 100


    Insert geometry Grade Feed (mm/rev) Cutting speed (m/min.)
    GF GC2135 0.08-0.12 140


    High speed steel drilling Diameter (mm) Grade Feed (mm/rev) Cutting speed (m/mm.)
    HSS drill 1-3 HSS 0.03–0.09 8–15
    Solid carbide drilling Diameter (mm) Grade Feed (mm/rev) Cutting speed (m/mm.)
    CoroDrill 840 3-12 GC1220 0.06-0.22 50
    Short hole drilling Diameter (mm) Geometry Grade peripheral/central Feed (mm/rev) Cutting speed (m/mm.)
    CoroDrill 880 12-14 LM GC4044/GC1044 0.04-0.09 140
    CoroDrill 880 14-36 LM* GC2044/GC1144 0.04-0.18 140
    CoroDrill 880 36-63 LM GC4024/GC1044 0.04-0.18 140

    *MS for peripheral insert

    Cutting performance comparison

    Cutting time comparison

    By applying the collective Sanmac knowledge in the upgrade of the standard Alloy 329, Alleima R&D engineers have increased the machinability of the material to a new level. That, combined with a low spread in the manufacturing process, will provide major benefits to customers using Sanmac 329.


    In the solution annealed and quenched condition Sanmac® 329 has an austenitic-ferritic microstructure, which is free from grain-boundary carbides and intermetallic phases. The ferrite content is 55 – 75%.

    Disclaimer: Recommendations are for guidance only, and the suitability of a material for a specific application can be confirmed only when we know the actual service conditions. Continuous development may necessitate changes in technical data without notice. This datasheet is only valid for Alleima materials.