Formation of a novel W-rim/Cu-core structure during direct laser sintering of W–Cu composite system

The direct laser sintering of a submicron/micron composite system consisting of 40 wt.% submicron W–20Cu powder and 60 wt.% micron Cu powder was performed via liquid phase sintering mechanism. The SEM and EDXS characterization shows the presence of a series of regularly-shaped W-rim/Cu-core structures after laser sintering. The metallurgical mechanism for the formation of such a novel structure was addressed.