Characterization of the Gas Tungsten Arc Welding (GTAW) joint of Armco iron nanostructured by Equal-Channel Angular Pressing (ECAP)

After Severe Plastic Deformation (SPD), the strength of Armco iron sharply increases with number Equal-Channel Angular Pressing (ECAP) passes. So, ultimate tensile stress (UTS) reached up to 800 MPa after eight passes, reflecting an increment around four times than as-received material strength. The original grain size annealed about 70 ?m also experimented drastic changes ECAP, reaching sizes approaching 300 nm. Samples were then welded by Gas Tungsten Arc Welding (GTAW) process varying voltage and current conditions. Metallographic analysis Light Optical Microscopy (LOM) Electron Backscatter Diffraction (EBSD), was carried out analyze weld penetration, Fusion Zone (FZ), microstructure morphology across Heat Affected (HAZ). Special attention given nanostructured base metal. A microstructural gradient observed throughout joint hardness reduction concerning but still superior without ECAP. temperature heterogeneity gave rise different morphologies like Widmanstätten ferrite FZ, especially at high heat inputs.