Study on the Improved Mechanical Properties of RAFM Steel After Dual Equal-Channel Lateral Extrusion: Reflected by Quantified Microstructure

Dual equal-channel lateral extrusion (DECLE) of reduced activation ferritic/martensitic (CLAM) steel was studied by a simulation-driven accurate experiment. Uniaxial tensile test and microstructural characterization technology such as EBSD, SEM, and OM were used to analyze the evolution of mechanical properties and microstructure. The results show that the manufactured sample can be divided into four regions based on the texture components and the microstructural patterns. The volume fraction of a 2, a 3, and z -type rolling textures increase with the increase of DECLE passes to the value of 32.8%, 40.6%, and 22.08%, while the textures of other types of rolling and shearing region do not show the monotonic increase or monotonic decrease against the DECLE passes. The tensile strength is weakened by the decrease of dislocation density caused by temperature rise but is strengthened by the deformation texture and high angular grain boundaries. The strengthening model was established to have revealed the above microstructure–strength relationship.