There are some differences in hardness between Hastelloy and titanium alloys, which is mainly due to the differences in their chemical composition, alloy structure and the manufacturing process used.
1. Hardness of Hastelloy
Hastelloy (especially Hastelloy C-276) is a high-performance alloy based on nickel, containing elements such as molybdenum, chromium and iron. The combination of these elements gives Hastelloy excellent corrosion resistance and high temperature performance. The hardness of Hastelloy is generally between Rockwell B 70-90, depending on its composition and processing status. Since it is mainly used for corrosion-resistant and high-temperature resistant applications, Hastelloy generally has good ductility and toughness rather than particularly high hardness.
2. Hardness of Titanium Alloy
The hardness of titanium alloy also depends on its composition and heat treatment. Titanium alloys are divided into different types (such as α alloys, β alloys, α-β alloys), and the hardness of each type is different. Pure titanium has a low hardness of about Rockwell B 40-50, while the hardness of titanium alloys that have been alloyed (such as titanium-aluminum and titanium-molybdenum alloys) will increase. For some specific types of titanium alloys, the hardness can reach above Rockwell B 80 or even higher.
3. Hardness comparison
Hastelloy: Most Hastelloy alloys have a hardness between Rockwell B 70-90. Although alloys such as Hastelloy C-276 and C-22 have strong corrosion resistance and high temperature resistance, their hardness is usually not as good as some titanium alloys with higher hardness.
Titanium alloys: Pure titanium has a lower hardness, but alloyed titanium alloys, such as titanium-aluminum alloys, have a higher hardness. Some high-strength titanium alloys can reach Rockwell B 80 or even higher, so some types of titanium alloys will exceed Hastelloy in hardness.
4. Application differences
Due to the difference in hardness, Hastelloy and titanium alloys usually play a role in different applications:
Hastelloy: Due to its excellent corrosion resistance and high temperature resistance, Hastelloy is more used in chemical processing, petrochemical, aerospace and other occasions with high corrosion resistance and high temperature requirements. Its hardness is suitable for use in these extreme environments, but hardness is not particularly important.
Titanium alloy: Titanium alloy is widely used in aerospace, shipbuilding, medical equipment and other fields. Titanium alloy has moderate hardness and very high specific strength, so it is more prominent in some applications that require high strength and light weight.
