Microstructural analysis on a creep resistant martensitic 9-12% Cr steel using the EBSD method

In this work, the martensite lath structure of a creep resistant 9-12% Cr steel was examined by electron backscatter diffraction. Parameters of interest were the misorientation of matrix boundaries, martensite lath width and subgrain size. It is demonstrated, that boundary misorientations do not exactly follow the classical models for austenite-martensite transformation, and show small, but systematic deviations. It is further shown to what extent high-temperature ageing and creep loading effect the evolution of martensite lath width and subgrain size.