What is the influence of the chemical composition of T91 steel on hot rolling

Grade T91 steel has several incomparable advantages, such as excellent room temperature and creep resistance, low linear expansion coefficient, low cost (9.5-11.5% alloy) and excellent structure for long-term stable operation. It has become an irreplaceable material for boiler steel pipe power plants with ultra-high critical pressure.

T91 steel is made of about 9% chromium and 1% molybdenum alloy, and is also called 9Cr1Mo steel according to its composition. T91 steel has a high hardness strip martensite phase under hot rolling conditions, so it needs to be tempered to reduce the hardness to obtain good cutting performance.

The recrystallization temperature of T91 steel is above 790. The lower tempering temperature has almost no effect on the structure and properties of T91 steel, while the higher tempering temperature will make the recrystallized structure happen to produce ferrite phase and uneven structure.