What's the Difference: Hastelloy G30 vs C276?
Hastelloy G30 and C276 are both members of the Hastelloy family of nickel-based superalloys renowned for their exceptional corrosion resistance in harsh environments. While they share some similarities, they also possess distinct differences in terms of chemical composition, mechanical properties, and applications. Let's delve into the detailed comparison between these two alloys:
1. Chemical Composition:
Hastelloy G30 UNS N06030:
Hastelloy G30 is a nickel-chromium-iron alloy with added tungsten and copper. It has a higher chromium and molybdenum content than Hastelloy C276, which enhances its resistance to localized corrosion and oxidizing environments.
- Nickel (Ni): 50%
- Chromium (Cr): 29%
- Iron (Fe): 14%
- Cobalt (Co): 5.8%
- Molybdenum (Mo): 2.5%
- Copper (Cu): 2.5%
- Tungsten (W): 1.5%
- Other Elements: Trace amounts of manganese, silicon, sulfur, phosphorus, carbon, and nitrogen.
Hastelloy C276 UNS N10276:
On the other hand, Hastelloy C276 is a nickel-molybdenum-chromium alloy with tungsten and iron. It offers superior resistance to a wide range of corrosive media, including highly oxidizing and reducing environments such as chlorides, sulfuric and hydrochloric acids, and seawater.
- Nickel (Ni): 57%
- Chromium (Cr): 16%
- Molybdenum (Mo): 16%
- Iron (Fe): 5%
- Tungsten (W): 3.5%
- Cobalt (Co): 2.5%
- Manganese (Mn): 0.5%
- Other Elements: Trace amounts of silicon, carbon, sulfur, phosphorus, and copper.
2. Mechanical Properties:
Werkstoff 2.4603 Hastelloy G30:
- Tensile Strength: 109 ksi (750 MPa)
- Yield Strength: 44 ksi (305 MPa)
- Elongation: 50%
- Hardness (Rockwell B): 89
2.4819 Hastelloy C276:
- Tensile Strength: 110 ksi (760 MPa)
- Yield Strength: 52 ksi (355 MPa)
- Elongation: 40%
- Hardness (Rockwell B): 100
3. Key Characteristics and Applications:
Nickel alloy G30:
- Outstanding resistance to oxidizing acids, particularly nitric acid and mixed acid environments containing phosphoric acid, hydrochloric acid, and fluorides.
- Excellent resistance to localized corrosion such as pitting and crevice corrosion.
- G30 can be used in high temperature environments up to 1800°F.
- Widely used in chemical processing industries, especially in applications involving nitric acid production, pickling operations, and scrubbers.
Nickel alloy C276:
- Exceptional resistance to a wide range of corrosive environments, including oxidizing and reducing acids, chlorine-containing media, seawater, and brine solutions.
- High resistance to stress corrosion cracking and pitting.
- C276 can be used in high temperature environments up to 1900°F.
- Versatile alloy used in various industries such as chemical processing, pollution control, pulp and paper production, and waste treatment.
4. Summary:
In summary, Hastelloy G30 and C276 are both highly corrosion-resistant alloys suitable for demanding industrial applications. While Hastelloy G30 excels in nitric acid environments and offers excellent localized corrosion resistance, Hastelloy C276 exhibits superior overall corrosion resistance across a broader spectrum of aggressive media. Choosing between these alloys depends on the specific corrosive environment and mechanical requirements of the application at hand.
