Features of the Ti-40Nb alloy prototype formation by 3D additive method

The structure of Ti-40Nb alloy prototype obtained by selective laser melting (SLM) on “VARISKAF 100MV” installation was considered by the methods of optical metallography, scanning and transmission electron microscopy. It was revealed that the most of the specimens’ surface is uniform flowed surface with typical banded structure formed by laying-on molten pools. The process of the individual layer formation was followed by drop formation. This leads to the porosity formation on the specimen’s surface. The structure of entire specimen is not homogeneous throughout the transverse section. The porosity of three kinds is observed. They are cavities of not full contact and melting of the layers, drawholes, gas pores. The porosity optimization requires more careful SLM modes selection. The alloy has a grain structure with anisotropy from small (2–8 µm) to medium (8–20 µm) grain size. The anisotropy of the specimen is formed in each layer and is retained during building of the specimen. The grains of microstruct...