Journal Published Online: 26 September 2016
Volume 5, Issue 5

EBSD Characterization of Pilgered Alloy 800H After Heat Treatment



Austenitic stainless steel alloy 800H pipes were received in an as-pilgered condition. The pilgering process produces high levels of cold work through complex deformation processes. The pipes are subsequently solution annealed. To assess the influence of heat-treatment parameters on 800H, samples of the as-pilgered material were heat treated in the temperature range 600°C–1200°C for varying lengths of time. Using electron backscatter diffraction (EBSD), the recrystallization dynamics and grain size of all samples was measured. Additionally, the kernel average misorientation and grain orientation spread methods were employed to qualitatively analyze fine details in the strain levels in the matrix of both deformed and recrystallized grains. For 1-h anneal times, it was found that recrystallization of 800H initiates above heat-treatment temperatures of 800°C, and complete recrystallization of deformed material occurs above heat-treatment temperatures of 950°C. No significant increases in average grain size were observed until temperatures reached in excess of 1000°C. Increasing the heat-treatment time to more than 1 h had a negligible effect on the grain size for every heat-treatment temperature that was assessed. In high-temperature applications, pipes typically fail because of diffusion-based creep mechanisms. Therefore, accurate control of the grain size and microstructure during heat treatments is obligatory. This work provides a framework for controlling manufacturing processes to produce favorable microstructures in 800H for creep-based applications.

Author Information

Beardsley, A.
Dept. of Mechanical Engineering, Univ. of Canterbury, Christchurch, NZ
Bishop, C.
Dept. of Mechanical Engineering, Univ. of Canterbury, Christchurch, NZ
Kral, M.
Dept. of Mechanical Engineering, Univ. of Canterbury, Christchurch, NZ
Pages: 23
Price: $25.00
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Stock #: MPC20160062
ISSN: 2165-3992
DOI: 10.1520/MPC20160062