Alloy 690 UNS N06690 WNR 2.4642 Seamless Cold Drawn Nickel Alloy Tube and Pipe
Description:
Alloy 690 is a high-chromium nickel alloy having excellent resistance to many corrosive aqueous media and hightemperature atmospheres. The alloy’s high chromium content gives it excellent resistance to caturisation, metal dusting, oxidation and sulfidation at high temperature. In addition to its corrosion resistance, alloy 690 has high strength, good metallurgical stability, and favorable fabrication characteristics.
alloy 690 (UNS N06690/W. Nr. 2.4642) is a high-chromium nickel alloy having excellent resistance to many corrosive aqueous media and hightemperature atmospheres. In addition to its corrosion resistance, alloy 690 has high strength, good metallurgical stability, and favorable fabrication characteristics.
The chemical composition of INCONEL alloy 690 is listed in Table 1. The substantial chromium content gives the alloy outstanding resistance to oxidizing chemicals and to high-temperature oxidizing gases.
The high level of nickel imparts resistance to stresscorrosion cracking in chloride-containing environments as well as to sodium hydroxide solutions. The properties of INCONEL alloy 690 are useful for various applications involving nitric or nitric/hydrofluoric acid solutions. Examples are tail-gas reheaters used in nitric acid production and heating coils and tanks for nitric/hydrofluoric solutions used in pickling of stainless steels and reprocessing of nuclear fuels.
The alloy’s resistance to sulfur-containing gases makes it an attractive material for such applications as coal-gasification units, burners and ducts for processing sulfuric acid, furnaces for petrochemical processing, recuperators, incinerators, and glass vitrification equipment for radioactive waste disposal. In various types of high-temperature water, alloy
690 displays low corrosion rates and excellent resistance to stress-corrosion cracking. Thus, alloy 690 is widely used for steam generator tubes, baffles, tubesheets, and hardware in nuclear power generation.
Available tube product forms
Straight
Seamless
Typical Applications
Heat exchangers
Steam Generators
High temperature applications exposed to caustic solutions
Typical manufacturing specifications
ASTM B167
Also individual customer specifications.
Industries predominantly using this grade
Chemical processing
Nuclear and power
Oil and gas
Temper | Annealed | |
---|---|---|
Tensile Rm | 86 | ksi (min) |
Tensile Rm | 590 | MPa (min) |
R.p. 0.2% Yield | 35 | ksi (min) |
R.p. 0.2% Yield | 240 | MPa (min) |
Elongation (2” or 4D gl) | ≥30 | % (min) |
Specific Heat (0-100°C) | 450 | J.kg-1.°K-1 |
Thermal Conductivity | 13.5 | W.m -1.°K-1 |
Thermal Expansion | 14 | mm/m/°C |
Modulus Elasticity | 211 | GPa |
Electrical Resistivity | 1.26 | μohm/cm |
Density | 8.2 | g/cm3 |
Element | Min | Max |
---|---|---|
C | - | 0.05 |
Si | - | 0.5 |
Mn | - | 0.5 |
P | - | 0.02 |
S | - | 0.015 |
Al | - | 0.5 |
Cr | 27 | 31 |
Cu | - | 0.5 |
Fe | 7 | 11 |
Ti | - | 0.5 |
Ni | Balance |