Microstructures of 2219-Al thin-walled parts produced by shaped metal deposition

A multi-layers single-pass thin-walled part was produced by shaped metal deposition and the macro-morphologies and microstructures were observed. Results show that the whole part exhibits a good metallurgical junction and fusion phenomenon. On a macro-level, many parallel stripes occur in the middle and bottom regions. The parallel stripes are equidistant distributed and coincident with the layers-interfaces. In top region, the dendritic grains dominate and the segregation of Cu-element is serious. In middle and bottom regions, the microstructures are varied, including equiaxed grains, columnar grains and planer grains. The grains arrange according a list-regular and the segregation of Cu-element is alleviated compared with top region. There are a lot of porosities and shrinkages in the part, whose sizes vary from 10 μm to 80 μm. Moreover, the porosities and shrinkages are more likely to occur in the interfaces.