Microstructure
Alloy 718 is an age-hardenable austenitic material. Strength is largely dependent on the precipitation of the primary phase during heat treatment.
Alloy 718 Characteristics
Good fabricability in the annealed condition;
Good tensile, fatigue, and creep-rupture strengths, up to 700℃;
High-temperature strength up to 700℃;
Good oxidation resistance up to 1000℃;
Excellent mechanical properties in cryogenic environments;
Good weldability by arc welding without susceptibility to post-weld cracking.
Corrosion Resistance
Alloy 718 has excellent corrosion resistance to many media. This resistance, which is similar to that of other nickel-chromium alloys, is a function of its composition. Nickel contributes to corrosion resistance in many inorganic and organic compounds (other than strongly oxidizing compounds) across a wide range of acidity and alkalinity. It also helps in combating chloride-ion stress-corrosion cracking. Chromium imparts the ability to withstand attack by oxidizing media and sulfur compounds. Molybdenum is known to contribute to resistance to pitting in many media.
Applications
Due to its high-temperature strength up to 700℃, excellent corrosion resistance, and ease of fabrication, Alloy 718 finds applications in many fields. Initially, it was used as a turbine disk material in aircraft jet engines, where resistance to creep and stress rupture was most important. Because of its properties, fabricability, and cost-effectiveness, it has since gained wider acceptance. Today, applications vary from highly stressed rotating and static components in gas turbines and rocket engines to high-strength bolting, springs, and fasteners, components in nuclear reactors and space vehicles, as well as high-temperature tooling for extrusion, such as for copper, and shearing. Another important recent application involves pump shafts and other highly stressed wellhead and downhole components in offshore drilling equipment. Particularly useful is the alloy for drilling equipment in sour (containing H2S, CO2, and chlorides) oil and gas wells.
We have products:
ASTM B983 Alloy 718 / UNS N07718 Nickel Alloy Seamless Tube; Bright Annealed Nickel Alloy Tube , ISO 9001 / PED , ANSI B36.19 ASTM B829 / ASME SB829 , ASTM B167 , ASTM B444; ASTM B366 Alloy 625 / UNS N06625 Nickel Alloy 45 / 90 Degree Elbow; Alloy 625 / UNS N06625 Nickel Alloy Welded Fitting, Elbow, Tee, Reducer; ASTM B670 Alloy 718 / N07718 Nickel Allloy Sheet / Strip; ASTM B443 / ASME SB443 Alloy 625 Nickel Alloy Sheet For Oil Industry; Alloy 601 / 625 / 718 Class300 Nickel Alloy Socket Welding Flange For Medical Tube; Alloy 825 / 718 Nickel Alloy Steel Sheet For Gas And Oil Industry; ASTM B443 Alloy 625 Nickel Alloy Steel Round Rod / Bar For Oil Industry; Alloy 601 / 617 Nickel Alloy Steel Square Rod / Bar, ASTM B166 For Chemical Industry; Petroleum Refining Used S31803/32750 Heat Exchanger Tube;