摘要
The microstructures of 316L stainless steel created by rapid solidification are investigated by comparing the similar microstructures of individual hatches of directed energy deposition additive manufacturing(DED-AM)and those of single,laser surface-melted tracks formed on a solid plate.High recoil pressure,which is exponentially dependent on the laser beam power density,induces convection of the melt pool,which causes formation of microstructural bands in the as-solidified microstructure.The microstructural bands are associated with changes in the chromium concentration and are a significant component of the inhomogeneous microstructure of DED-AM.
