Haynes 230 vs Inconel 718 – What’s the Difference

When it comes to high-temperature, corrosion-resistant alloys, two of the most popular options are Haynes 230 and Inconel 718. Both alloys have a variety of uses, including aerospace components and industrial applications. But which one should you choose? Let’s take a look at the differences between Haynes 230 and Inconel 718.

Thermal Properties

When comparing the thermal properties of Haynes 230 and Inconel 718, it is important to note that each alloy has its own unique set of characteristics. Haynes 230 has a higher melting point than Inconel 718 (2,600°F compared to 2,415°F), making it more suitable for applications requiring resistance to higher temperatures. However, when exposed to temperatures below 500°F, Inconel 718 performs better than Haynes 230 in terms of the creep strength and oxidation resistance.

Mechanical Properties

The mechanical properties of both alloys are similar; they both have good tensile strength and ductility, with Inconel 718 being slightly stronger than Haynes 230. Additionally, when tested for fatigue strength at room temperature, both alloys performed equally well; however, at elevated temperatures, Inconel 718 performed better than Haynes 230 in this area.

Corrosion Resistance

In terms of corrosion resistance, both alloys perform similarly under normal conditions; however, when exposed to more extreme environments containing chloride ions or other corrosive agents such as sulphuric acid and nitric acid, Inconel 718 provides superior protection due to its higher chromium content (17-21% vs 9-11%). Additionally, while both alloys are resistant to oxidation when exposed to air at high temperatures (above 1,400°F), Inconel 718 exhibits better performance in this area due to its higher nickel content (50-55% vs 33-38%).

Composition

Haynes 230 is an alloy that contains 22% chromium, 3% silicon, 1% manganese, 1% molybdenum, and trace amounts of iron, carbon, and boron. Inconel 718 is an alloy that contains 50% nickel, 18-21% chromium, 5-7% cobalt, 3-5% iron, 2-4% manganese, 1-2% molybdenum, 1-2% titanium, and trace amounts of carbon and aluminium.

Melting Point

Haynes 230 has a melting point of 2200 degrees Celsius, while Inconel 718 has a melting point of 1300 degrees Celsius.

Tensile Strength

Haynes 230 has a tensile strength of 930 MPa, while Inconel 718 has a tensile strength of 1040 MPa.

Yield Strength

Haynes 230 has a yield strength of 550 MPa, while Inconel 718 has a yield strength of 690 MPa.

Modulus of Elasticity

Haynes 230 has a modulus of elasticity of 193 GPa, while Inconel 718 has a modulus of elasticity of 210 GPa.

Density

Haynes 230 has a density of 8.4 g/cm3, while Inconel 718 has a density of 8.0 g/cm3.

Conclusion:

Both Haynes 230 and Inconel 718 offer excellent corrosion resistance and mechanical properties that make them suitable for a variety of industrial applications. However, depending on your application’s specific requirements—such as temperature range or exposure environment—one alloy may be better suited than the other. Ultimately it is up to you to decide which one best fits your needs. If you’re still not sure which alloy is right for your application after reading this article, then we recommend consulting with an experienced professional who can provide additional guidance on selecting the appropriate material for your project.