What is the difference between Alloy 925 and 718?

Alloy 925 and Alloy 718 are quite different in composition. However, because Alloy 925 achieves similar tensile strength as Alloy 718 it is increasingly being used as a lower cost substitute in numerous Oil and Gas related applications.

Alloy 925 is a nickel-based alloy, which means that the largest element present is nickel at 38-46% of the total. It also contains iron, chromium and molybdenum, but at lower proportions. In comparison, Alloy 718 contains 50-55% nickel, with similar levels of chromium and molybdenum. As nickel is an expensive alloying addition, the increased content of nickel in Inconel 718 increases its price relative to Incoloy 925 by up to 20%.

The mechanical properties of Incoloy 925 are quite similar to that of Inconel 718, as they both achieve their high strength through precipitation-strengthening. Small additions of titanium, aluminium and niobium combine to form fine precipitates throughout the metal when it is subjected to a secondary heat treatment process. These precipitates help to ‘pin’ the microstructure of the metal when it is subject to an external load, increasing its strength and toughness.

Langley Alloys stocks Alloy 718 as round bars from 5/8”-10” diameter (15.87-254mm).

Alloy 925 is less readily available in the smallest diameters, so our stock typically starts at 4”-10” (101.6-254mm) diameter.

For More Information  

For more information about our range of alloys, please contact Langley Alloys today.