Fig. 3: Microstructural features of weld cross-sections fabricated with different filler materials.

a, d, g Ultra-depth-of-field microscope characterization of welds fabricated with the ER2319, the ER4043 and the ZCASW filler materials, respectively. b, e, h The IPF of the melting zones fabricated with the ER2319, the ER4043 and the ZCASW filler materials. c, f, i Dendrites size statistics of the melting zones fabricated with the ER2319, the ER4043 and the ZCASW filler materials. j STEM-HAADF image in one equiaxed dendrites region and corresponding EDX mapping of the main elements (Al, Zr, Cu and Mg) shown in (k). l Diffraction pattern of the L1₂-Al₃Zr precipitate in the [0\(1(\_)\)\(1(\_)\)] direction. m Diffraction pattern of the interface between the Al matrix and L1₂-Al₃Zr in the [0\(1(\_)\)1] direction. n HRSTEM-HAADF image taken at the α-Al/L1₂-Al₃Zr interface along the [0\(1(\_)\)1]_Al([0\(1(\_)\)1]_L12-Al3Zr) zone axis, with the inset showing the corresponding FFT pattern. o Magnified view of the marked yellow area in (n), showing atomic coincidence across the interface between these two crystals.