Hastelloy C276 and monel 400

What is the difference between Hastelloy C276 and monel 400?

Monel Alloy 400 relies heavily on the addition of copper to its composition, while Hastelloy C276 incorporates molybdenum, chromium and tungsten to provide greater solid solution strengthening, resulting in higher tensile strength.

What is the heat treatment process for Hastelloy C276?

While Monel 400 alloy relies primarily on copper additions to its composition, Hastelloy C276 alloy has additions of molybdenum, chromium, and tungsten, which provide greater solid solution strengthening and thus improved tensile strength.

What is Monel 400 used for?

Monel 400 is widely used in the chemical, petroleum and marine industries. It resists corrosion in a wide range of marine and chemical environments, from pure water to non-oxidizing mineral acids, salts and bases.

Will Monel 400 rust?

Monel 400 is a nickel-copper alloy characterized by good corrosion resistance, good weldability, and medium to high strength. It also resists attack by hot seawater and steam, as well as alkaline solutions and salts.

Alloy 400 v Hastelloy C276

Chemical Composition

	Ni	Cu	Mo	Cr	W	Fe	Mn	Co	C	Si	Others
Alloy 400	63-70	28-34	–	–	–	2.5	2	2	0.3	0.5	0.024
Hastelloy C276	Balance	–	15-17	14.5-16.5	3-4.5	4-7	1	2.5	0.01	0.05	0.37

While the composition of Monel 400 is largely determined by the addition of copper, Hastelloy C276 has added molybdenum, chromium, and tungsten, which provide greater solid solution strengthening, thus increasing tensile strength. Tight control of impurities such as silicon and carbon in Hastelloy C276 improves its weldability, but as always, nothing comes for free, which also increases production costs.

Mechanical Properties

	Alloy 400	Hastelloy C276
UTS (MPa)	600	690
0.2% Proof Strength (MPa)	415	310
Elongation (%)	20	40
Hardness (HRC max %)	35	45
Condition	Cold worked and stress relieved	Cold worked and solution annealed

The alloying elements in Hastelloy C276 provide increased tensile strength and hardness, making it suitable for high temperature applications where structural stability is critical. At high temperatures, the microstructure of any alloy becomes more unstable, which can lead to the precipitation of phases that are detrimental to the material. Careful use of additives in Hastelloy C276 can reduce this risk.

Corrosion Resistance

Both alloys are known for their corrosion resistance, but their protective properties differ in different environments. The copper element in Monel 400 alloy provides excellent corrosion resistance in oxidizing environments at room temperature, but its corrosion resistance decreases at high temperatures. In contrast, the chromium and molybdenum in Hastelloy C276 alloy provide strong oxidation resistance even at high temperatures and provide additional protection in reducing atmospheres.

Physical Properties

	Alloy 400	Hastelloy C276
Density (g/cm³)	8.80	8.89
Thermal Conductivity (W/m^oC)	22.0	9.8
Young's Modulus (GPa)	179	205

Applications

Both alloys are widely used in the chemical processing industry. However, their application areas differ:

Alloy 400: Ideal for valves, pumps, gasoline and fresh water tanks, process vessels, marine equipment and heat exchangers.

Hastelloy C276: Suitable for use in heat exchangers, reaction vessels, evaporators and even the recovery of "sour" natural gas.

Conclusion

Gnee Steel is a supplier of Hastelloy C276 And Monel 400 in tubes, pipes, plates, strips, plates, round bars, flat bars, forged billets, hexagons, wire and extrusions. We work with steel mills to provide customers with 625 alloy, and its products meet or exceed many leading industry standards, including ASTM, ASME, SAE, AMS, ISO, DIN, EN and BS standards.
Gnee Steel stocks and sells Hastelloy C276 And Monel 400 tubes, pipes, plates, strips, plates, round bars, flat bars, forged billets, hexagons, wire and extrusions. You are welcome to contact us for a quote at any time at ss@gneesteel.com

What Is The Difference Between Hastelloy C276 And Monel 400?