Investigation of the Grain Growth Evolution in the AISI 304H Austenitic Stainless Steel

Abstract

Abstract:The austenitic stainless steels usually present an excellent combination of corrosion resistance and mechanical properties such as ductility in the annealed condition and high yield strength after cold deformation. Solution annealing in the AISI 304H is recommended before deformation process in order to improve ductility. However, long annealing during solution annealing can cause GG (grain growth) or AGG (abnormal grain growth) in the AISI 304H. In these cases, ductility is strongly decreased. Therefore, GG or AGG must be avoided during solution annealing. In this article, grain growth during solution annealing of the AISI 304H samples was determined. Samples of the AISI 304H were annealed at 1,100 °C for solution-annealing times varying from 15 min to 180 min. The results show that AGG took place for samples annealed at 1,100 °C for 30 min. In this condition, grain size reached 70 ± 10 µm. After annealing solution at 1,100 °C for 180 min, grain size reached 120 ± 20 µm. In summary, the results shown that solution annealing at 1,100 °C even for relatively short annealing promotes the prompt increase of the grain size.