| Abstract Scope |
The shaping and joining of materials by way of solid-state deformation, results in grain refinement due to dynamic recrystallization and can offer significant advantages for extreme environment applications. In alloy systems where precipitation hardening is of importance, careful attention to the specific process conditions need to be taken into consideration to ensure the desired microstructure is attained for the specific use environment. Poor selection of the processing variables can result in layered microstructures presenting locally inhomogeneous constitutive response, or meta-stable microstructures that can transform deleteriously upon use or when exposed to extreme environments. Improved knowledge of the microstructural evolution during processing is therefore beneficial and can allow selection of more forgiving processing conditions, for more tolerant microstructures. Examples will be given and discussed for current systems that have resulted in such microstructures and the process modifications that have allowed the formation of improved, environmentally tolerant microstructures. |