ASTM A213 Grade T9 Alloy Steel Seamless Tube Heat Exchange Tube

ASTM A213 Grade T9 Alloy Steel Seamless Tube Heat Exchange Tube

ASTM A213 Grade T9 is a classic medium-chromium alloy steel with a long history of use in high-temperature and high-pressure industries. It strikes an excellent balance between high-temperature strength, oxidation resistance, and cost, making it a key material for the manufacture of power plant boiler superheater tubes and petrochemical furnace tubes. Although replaced in some applications by newer steel grades like T91, which offer superior performance, T9 remains widely used in many existing equipment and design conditions.

Comparison with Other Common Grades

Comparison with T5 (5Cr-0.5Mo): T9's higher chromium and molybdenum content improves its high-temperature strength and oxidation resistance compared to T5.

Comparison with T11 (1.25Cr-0.5Mo) / T22 (2.25Cr-1.0Mo): T9's chromium content is significantly higher than that of T11 and T22, resulting in improved oxidation and corrosion resistance, but also a higher cost.

Compared to T91 (9Cr-1Mo-V-Nb): T91 is a modern, improved version of T9 that incorporates vanadium (V) and niobium (Nb). Through precipitation strengthening, its high-temperature strength is far superior to that of traditional T9. It is currently one of the preferred materials for supercritical and ultra-supercritical power plants. T9 can be considered the predecessor of T91.

Chemical Composition (wt %) of ASTM A213 T9 Alloy Steel Seamless Tubes

Mechanical Properties of ASTM A213 T9 Tubes

The mechanical strength of ASTM A213 Gr T9 Seamless Tubes makes them suitable for demanding service:

Heat Treatment Requirements of A213 T9 Alloy Steel Seamless Tubes

Application