inconel 738 is a nickel-chromium superalloy which provides exceptional strength and durability. This alloy is used in a variety of industries and applications where high-temperature performance is required. It is also highly corrosion resistant, making it an excellent choice for many applications.
This alloy has a wide range of application, from aircraft engines to medical implants and more. It is available in several forms, including forging billet (AMS 5940), rod and bar for machining, extruded section and wire rod.
The chemical composition of inconel 738 is composed of nickel (58%), chromium (20-23%), cobalt (9-11%), molybdenum (2-3%), and iron (7-9%) with trace amounts of aluminum, titanium, tungsten, manganese, copper, sulfur and carbon. It also contains 0.4% yttrium for increased corrosion resistance.
The corrosion resistance of IN738 in seawater with higher sulphate content was studied. The results show that IN738 is susceptible to sulfate corrosion attack and this may be caused by the interaction between the sulphate and the base metal, which promotes perforation and accelerates the corrosion attack.
IN738 was tested in thermo-mechanical fatigue using a DSI Gleeble thermal simulator over the temperature range of 500-900 deg C with plastic strains ranging from 0.1 to 0.8%. It was found that the IN738 parent alloy exhibited superior strength compared to that of a direct welded ductile iron base material under the same test conditions.
Liquid droplet erosion of bellows made from IN738 and Inconel 600 was examined through vibratory cavitation equipment, jet impingement erosion apparatus and a surface roughness tester. The results showed that the rate of liquid droplet erosion of IN738 was significantly lower than that of its counterpart Inconel 625.