Microstructural evolution and mechanical properties of functionally gr…

“Microstructural evolution and mechanical properties of functionally graded austenitic–low-carbon steel produced via directed energy deposition”

Highlights:
• This study investigated the FGM via InssTek's Technology as an alternative to the existing reactor pipe joining method and designed an FGM comprising austenite SS316L and low-carbon steel.
• 5 layers with different compositions were produced. The bottom layer was deposited using 100% low-carbon steel on an S45C carbon steel plate. The following 3 layers were deposited using low-carbon steel and SS316L in weight ratios of 75:25, 50:50, and 25:75. The top was deposited using 100% SS316L powder. Delamination and cracking didn’t occur.
• The OM and SEM images of the cross-sectional microstructure of the as-prepared FGM viewed perpendicular to the building direction showed no micro-cracks, delamination, or unmelted powder particles. In addition, EDS analysis indicated that the composition of each layer was relatively uniform, and no major precipitation was observed.