Alloy 725

UNS N07725
Trade Name Inconel 725 (1)

General scope

Alloy 725 is highly resistant to corrosion and is age hardenable for extremely high strength. It is used in a broad range of severe corrosive environments. The strength of age-hardened A725 is twice that of A625 annealed. Strength in A725 is obtained by heat treatment and can also be cold worked for even higher strength. There is also a high resistance in reducing and oxidizing environments and increased resistance to pitting and crevice corrosion in sea water and stress corrosion cracking.

Due to outstanding corrosion resistance and high strength, applications for this alloy are used for hangers, side pocket madrels, springs and polished bore receptacles for sour gas service. The petrochemical and processing industries are good candidates for this alloy. A725 is also used for high strength fasteners in marine applications to resist corrosion, pitting and crevice attack in sea water.

  • A hardness level of 43 HRC max. is allowed in NACE MR0175 when elemental sulphur is not present.

Chemical composition

C Si Mn P S Cr Ni Mo NbCb Ti Al Fe
Min 19.00 55.00 7.00 2.75 1.00 0.00
Max 0.03 0.20 0.35 0.015 0.010 22.50 59.00 9.50 4.00 1.70 0.35 0.00

Mechanical properties

Condition: Solution Annealed and Age Hardened (Minimum values)

NACE MR0175 limits the supply hardness to 43 HRC max. *
U.T.S 150 KSI Min
0.2% Proof Stress 120 KSI Min
Elongation 20 %

Condition: Solution Annealed and Age Hardened (Maximum values)

NACE MR0175 limits the supply hardness to 43 HRC max. *
U.T.S 150 KSI Min
0.2% Proof Stress 140 KSI Min
Elongation 20 %
Size range: 1”∅ - 9”∅

Primarily manufactured in:

  • Dubai, UAE
  • Edmonton, Canada
  • Houston, Texas
  • Sheffield, England
  • Singapore