Incoloy 925

Incoloy alloy 925 (UNS N09925) is an agehardenable nickel-iron-chromium alloy with additions of molybdenum, copper, titanium and aluminum. The titanium and aluminium are specifically added to give a strengthening of the alloy during ageing, as Ni3(Al, Ti) gamma (‘ϒ’) prime precipitates form throughout the alloy matrix and greatly increases the hardness and strength in a similar way to alloy 718 and 725.

The alloy is designed to provide a combination of high strength and
excellent corrosion resistance. The nickel content is sufficient for protection against chloride-ion stresscorrosion cracking.

The nickel, in conjunction with the molybdenum and copper, also gives outstanding resistance to reducing chemicals. The molybdenum aids
resistance to pitting and crevice corrosion.

The alloy’s chromium content provides resistance to oxidizing environments. The titanium and aluminum additions cause a strengthening reaction during heat treatment.

Incoloy alloy 925 is used in various applications requiring a combination of high strength and corrosion resistance. Because of the alloy’s resistance to sulfide stress cracking and stress-corrosion cracking in “sour” (H2S containing) crude oil and natural gas, it is used for down-hole and surface gaswell components including tubular products, valves, hangers, landing nipples, tool joints and packers.

The alloy is also useful for fasteners, marine and pump shafting and high-strength piping systems.