Investigating the influence of various tool path trajectories on the anisotropic behavior of bulk NiCrMo-3 alloy fabrication by WADED process

Abstract

This study delves into the Wire Arc directed energy Deposition (WADED) process, exploring the impact of four tool path trajectories designated as bidirectional contour (S1), bidirectional spiral (S2), Fermat's spiral (S3), and Fermat's zigzag (S4) on the deposition of a regular cubic solid structure of NiCrMo-3 alloy. The research focuses on understanding how these trajectories influence both microstructural heterogeneity and anisotropic mechanical response. It has been shown that the WADED processed NiCrMo-3 alloy displays prominent dendritic microstructure, with varying dendritic arm spacing and growth orientation angle across S1 to S4. S2 and S4 favor more columnar to equiaxed transition due to relatively lower cooling rates and G/R values along with a higher extent of Laves and carbide precipitation compared to S1 and S3. Texture analysis reveals S1 and S3 exhibit a predominant cube {001} < 100 > texture, while S2 transitions to Goss {110} < 001 > texture, and S4 displays a more random texture with higher intensity in copper {112} < 111 > and brass {110} < 1-12 >. Microhardness exhibited slight anisotropy (within 3%), with S4 (227.77HV0.5) having the highest microhardness. The YS and UTS were lower in the build direction (< 001 > (S)) compared to the horizontal direction (<001 > (S)) in all samples. S2 showcased maximum YS (334.5 MPa) and UTS (655 MPa) values while minimum anisotropy (<= 2%) was observed in S4 along with comparable YS (330 MPa) and UTS (645.5 MPa)