Hastelloy is a registered trademark name of Haynes International, Inc. The Hastelloy trademark is applied as the prefix name of a range of corrosion-resistant metal alloys under the material term “superalloys” or “high-performance alloys”.
Within corrosion applications Hastelloy alloys are often chosen due to their relatively attractive price/performance ratio. In many corrosion media only Tantaline shows a dramatically better cost/performance ratio than Hastelloy.
The predominant Hastelloy alloying ingredient is metal nickel. Other alloying ingredients are added to Hastelloy includin varying percentages of the elements molybdenum, chromium, cobalt, iron, copper, manganese, titanium, zirconium, aluminum, carbon, and tungsten.
The primary function of the Hastelloy alloys is that of effective survival under high-temperature, high-stress service in a moderately to severely corrosive, and/or erosion prone environment. Hastelloy alloys are used for many applications including pressure vessels, nuclear reactors, chemical reactors, as pipes and valves in chemical industry.
HASTELLOY B-3 alloy is a member of the nickel-molybdenum family of Hastelloy alloys. Hastelloy B-3 is the alloy in the Hastelloy family that shows best resistance to hydrochloric acid. Ref 2
HASTELLOY C-276 alloy is a nickel-molybdenum-chromium wrought alloy that is generally used as corrosion-resistance. Hastelloy c-276 (Hastelloy C276) is among the more well known Hastelloy grades for general corrosion service. Hastelloy C-276 alloy is an improved wrought version of Hastelloy alloy C. Ref 2
HASTELLOY C-4 alloy is a nickel-chromium-molybdenum Hastelloy alloy with good high-temperature stability. The Hastelloy C-4 is an Hastelloy grade, that resists the formation of grain-boundary precipitates in weld heat-affected zones. Hastelloy C-4 alloy also has excellent resistance to stress-corrosion cracking and to oxidizing atmospheres. Hastelloy C-4 is also used in a varity of chemical process environments. Ref 2
Hastelloy G is an nickel-chromium-iron-molybdenum alloy developed for corrosion resistance in both oxidizing and reduceing media. Hastelloy G shows good resistance to sulfuric and phosphoric acids. Hastelloy G may further handle both acid and alkaline solutions.
HASTELLOY X alloy - a nickel-chromium-iron-molybdenum alloy - has been developed to combine oxidation resistance, fabricability and high-temperature strength. Hastelloy X is also It has also been found to be resistant in petrochemical applications. Ref 2
2) According to Haynes International Sales Material