Texture development and microstructure evolution in metastable austenitic steel processed by accumulative roll bonding and subsequent annealing

摘要

In this paper, microstructure and texture development in a Fe-24Ni-0.3C metastable austenitic steel processed by accumulative roll bonding (ARB) and subsequent annealing was studied. Microstructural observations and crystallographic analysis were carried out by FESEM/ EBSD. The results showed that elongated ultrafinegrained austenite having 300 nm in thickness surrounded by high angle boundaries was obtained after 6 cycles of the ARB process. It was found that 1-cycle ARB-processed specimen exhibited Copper ({112} <111>) component as main texture, while by increasing the number of ARB cycles, it deviated to S component ({123} h634i) at 2 cycles or Brass component ({110} <112>) at 6-cycle. Annealing of 6-cycle ARB-processed specimen at 873 K for 1.8 ks resulted in the formation of an austenite with mean grain size of 2.5 μm having strong Cube recrystallization texture ({100} <001>).