Alloy 690 is a high-chromium nickel alloy that exhibits excellent resistance to many corrosive aqueous media and high temperature environments. It has good fabrication characteristics, metallurgical stability and high strength.However, the alloy shows excellent resistance to stress-corrosion cracking and low corrosion rates under various high-temperature solutions.
Inconel 690 is a high chromium content version of INCONEL alloy 600 with excellent resistance to many oxidising acids and salts and some resistance to sulphidation at elevated temperatures. 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.
Inconel 690 alloy is surface treated by laser melting technology, which can improve its surface properties, and has good corrosion resistance and high strength as a steam generator heat transfer tube material in pressurized water reactor power stations. It can not only resist the occurrence of intergranular corrosion, but also resist the development of intergranular stress corrosion cracking, to ensure the reliable operation of the equipment.
Inconel 690 Characteristic：
- Excellent inoxidability in the high temperature.
- Good resistance to carbonizing.
- Good inoxidabilitiy in sulfur atmosphere
- Good mechanical property in both room temperature and high temperature.
- Good resistance to stress corrosion cracking, 690 have high creep rupture strength since it limits the carbon content and grain size, so recommend to use for above 500℃ environment.
Inconel 690 Chemical Composition
Inconel 690 Physical Properties
Inconel 690 Mechanical Properties (Minimum value at 20℃)
|Tensile Strength (σb/MPa)||Yield Strength (σp0.2/MPa)||Elongation (σ5/%)|
- Bars & Rods & Foring Ring /Flanges
- Sheet & Plate
- Strip & Coil
- Welding Wire &Spring wire
- Seamless Tube & Welded Pipe
»Round Bar & Square Bar & Hexagon Bar
● Diameter : φ8～φ300mm Length:10mm-6000mm
● Hot forging, Hot Rolling, Cold Drawing
● Bright Surface, Polished Surface, Black Surface
»Tube & Pipe:Seamless Tube& Welded Pipe
● Cold Drawing Seamless Pipe： φ1.0～φ220mm
● Hot Extrusion pipe: φ50～φ250mm
● Others : U Blend Tube and Elbow
»Hot Rolled Plate & Cold Rolled Sheet
● Cold Rolling Sheet Thickness: ≦2.0mm Width:≦1500m
● Hot rolling Plate Thickness: ≧4.0mm Width: ≦2500m
»Strip & Tape Ribbon
● Thickness: ≧ 0.01mm Width: 15mm-300mm
● Cold rolling BA Strip, Hard & Soft Condition
»Straight Length Wire & Spool Wire
● Welding Wire: φ 0.1mm～6.0mm Cut length Rod: φ1.0～φ8.0mm
● Package : 5-25kg/Spool or Box
Alloy 690 Applications
- The tray,basket and tool clamp in the heat treatment factory.
- Steel shares at annealing and radiation control, high-speed gas burners, Industrial furnace silk screen.
- Separate tank of ammonia reforming and catalytic support grid of nitric acid producing.
- Exhaust system parts
- Solid waste incinerator’s combustion chamber
- Channel support and soot dealing parts.