Nickel alloy Inconel® 718 (UNS N07718, DIN 2.4375) is a widely used nickel-based alloy with a number of alloying elements added.
As a nickel-based alloy, it is virtually non-magnetic. Although it may contain up to 20% iron by weight, most people would consider it a non-ferrous metal and describe it as a superalloy due to its properties at elevated temperatures.
Inconel 718 retains most of its mechanical properties at temperatures up to 650 degrees Celsius (1200 degrees Fahrenheit), although it resists oxidation at higher temperatures.
Nickel-based alloys such as Inconel 718 will work harden during machining, drilling, and fabrication. Given that it is already a high-strength alloy when supplied in the aged condition, careful selection of tools, coolants, and CNC machine settings is required.
Inconel 718 can be welded easily, and if welded to itself, a matching filler metal is typically used.
Comparing Inconel 718 to Inconel 625, Inconel 625 has a higher alloy content, so it has improved corrosion resistance in most environments, but it costs more. However, Inconel 718 has higher strength due to a combination of alloying additives and heat treatment that allows it to be age-hardened.
