AL-6XN® alloy is corrosion-resistant, cost-effective, and available in whatever form you need.

When Allegheny Ludlum developed AL-6XN® alloy (N08367), they intended to create an austenitic stainless alloy that could be made in all product forms and would have superior corrosion resistance properties. AL-6XN is the leading 6Mo stainless alloy due to its excellent chemical, corrosion resistant, mechanical, and high temperature properties.

Chemical Composition of AL-6XN Alloy

AL-6XN's outstanding resistance to corrosion is due to higher concentrations of the following elements:
  • Nitrogen – Slows the formation of chi phase during manufacturing and field welding
  • Chromium – Provides good resistance to oxidizing environments
  • Molybdenum – Improves resistance to chlorides
  • Nickel – Stabilizes the austenitic microstructure and improves overall general corrosion resistance
ElementTypicalAllowable

N08367

Carbon (C)0.020.03 maximum
Manganese (Mn)0.402.00 maximum
Phosphorus (P)0.0200.040 maximum
Sulfur (S)0.0010.030 maximum
Silicon (Si)0.401.00 maximum
Chromium (Cr)20.520.00 – 22.00
Nickel (Ni)24.0023.50 – 25.50
Molybdenum (Mo)6.26.00 – 7.00
Nitrogen (Ni)0.220.18 – 0.25
Copper (Cu)0.20.75 maximum
Iron (Fe)BalanceBalance

Alloy Chemical Comparison

Super Austenitic Duplex Traditional
AL-6XN

(UNS N08367)

254 SMO

(UNS S31254)

904L

(UNS N08904)

2507

(UNS S32750)

2205

(UNS S32205)

1.4435

(UNS S31603)

316L

(UNS S31603)

% Carbon 0.020 0.015 0.015 0.030 0.030 0.030 max 0.010
% Chromium 20.5 20.0 20.5 25.0 21.0 – 23.0 17.0 – 19.0 16.0 – 18.0
% Nickel 24.0 18.0 24.5 7.0 4.5 – 6.5 12.5-15.0% 10.0 – 14.0
% Molybdenum 6.2 6.1 4.5 4.0 2.5 – 3.5 2.5 – 3.0 2.0 – 3.0
% Nitrogen 0.22 0.20 0.30 0.14 – 0.20 0.10 0.10 – 0.16
% Iron (Fe) 48 54 47 Balance Balance Balance Balance
% Manganese 0.4 0.7 1.6 1.2 2.0 2.0 max 2.0
% Phosphorous 0.020 0.030 0.045 0.035 max 0.030 0.045 max 0.045
% Sulfur 0.001 0.010 0.035 0.02 0.02 0.025 0.030
% Silicon 0.40 0.40 0.50 0.80 max 1.00 1.00 max 1.00
% Copper 0.1 0.7 1.5 0.11

Physical Properties of AL-6XN Alloy

Due to the stable, face-centered cubic crystal structure, commonly referred to as austenitic structure, AL-6XN alloy can be easily used in fabrication. AL-6XN alloy is a good alternative to titanium in condenser tubing applications, as a result of the excellent physical properties listed below.

PropertyValue
Density0.291lb/in3
8.06 g/cm3
Modulus of Elasticity28.3 x 106 psi
195 GPa
Melting Range2410 – 2550°F
1320 – 1400°C
Thermal Conductivity
68 – 212°F
20 – 100°C

6.8 Btu/hr • ft • °F
11.8 W/mK
Coefficient of Expansion
68 – 212°F
20 – 100°C

8.5 • 10-6/°F
15.3 • 10-6/°C
Specific Heat Capacity0.11 Btu/lb • °F
500 J/kg • K
Electrical Resistivity535 Ohm • circ mil/ft
0.89 µohm • cm
Magnetic Permeability
Fully annealed 0.5" plate
65% cold-worked plate

1.0028 Oersted
1.0028 (µ at 200H)
Scaling Temperature1885°F
1030°C