Comparative Study of Additive Manufacturing Techniques and Post-Processing on Microstructure and Properties of 17-4PH Stainless Steel and GRCop-42 Copper Alloy: Sintering Optimization vs Recrystallization Annealing

This study compares the effects of additive manufacturing (AM) techniques—binder jetting (BJ), directed energy deposition (DED), and cold spray (CS)—and post-processing (sintering, recrystallization annealing) on the microstructure and properties of 17-4PH stainless steel and GRCop-42 copper alloy , samples were fabricated via AM and conventional methods, followed by post-processing under optimized conditions (e.g., H₂ sintering at 1300°C for 17-4PH; annealing at 700°C for GRCop-42) , characterization included XRD, SEM, EBSD, hardness testing, electrochemical corrosion analysis, and thermal conductivity measurements , key findings demonstrate that BJ with H₂ sintering reduces porosity in 17-4PH by 5% and improves hardness by 15% compared to casting, while DED-processed GRCop-42 exhibits 20% higher thermal conductivity post-annealing than cold-sprayed counterparts , statistical analysis (ANOVA, α=0.05) confirmed the significance of sintering atmosphere (p<0.01) and annealing temperature (p<0.05) on final properties and these results identify optimal AM-post-processing synergies, advancing the deployment of high-performance alloys in aerospace and industrial applications.