Hastelloy X is a nickel-chromium-iron-molybdenum superalloy with outstanding  high temperature strength, oxidation resistance, and fabricability. Alloy X’s  oxidation resistance is excellent up to 2200° F. This nickel steel alloy has  also been found to be exceptionally resistant to stress-corrosion cracking in  petrochemical applications. Matrix stiffening provided by the molybdenum content  results in high strength in a solid-solution alloy having good fabrication  characteristics. Although this nickel alloy is primarily noted for heat and  oxidation resistance it also has good resistance to chloride stress-corrosion  cracking, carburization, and excellent resistance to reducing or carburizing  atmospheres. Two common conditions that often lead to early failure in high  temperature alloys, carburization and nitriding, Hastelloy X resists.

What are the characteristics of Hastelloy X?

· Outstanding oxidation resistance through 2000° F

· Resistant to carburization and nitriding

· Excellent high temperature strength

· Good resistance to chloride stress-corrosion cracking

Chemical Composition, %

In what applications is Hastelloy X used?

· Gas turbines

· Petrochemical industry

· Industrial furnaces

· Heat treating equipment

· Nuclear engineering

· Jet engine combustion chambers

· Aircraft cabin heaters

· Turbine exhaust components

Alloy X is one of the most widely used nickel base superalloys for gas  turbine engine combustion zone components such as transition ducts, combustor  cans, spray bars and flame holders as well as in afterburners, tailpipes and  cabin heaters. It is recommended for use in industrial furnace applications  because it has unusual resistance to oxidizing, reducing and neutral  atmospheres. Hastelloy X is also used in the chemical process industry for  retorts, muffles, catalysts support grids, furnace baffles, tubing for pyrolysis  operations and flash drier components.

Fabrication with Hastelloy X

Alloy X has excellent forming and welding characteristics. It can be forged  and, because of its good ductility, can be cold worked. It can be welded by both  manual and automatic methods including shielded metal arc, gas tungsten arc, gas  metal arc and submerged arc processes. The alloy can also be resistance welded.  For hot forming, the alloy should be heated to a starting temperature of 2150° F  (1175°C).

ASTM Specifications

Mechanical Properties

Representative Tensile Properties, sheet