The Effect of Interface Orientation During Uniaxial Tension of Functionally Gradient Materials of a Stainless Steel-Copper System Formed by the Wire-Feed Electron Beam Additive Manufacturing

The influence of tensile stress on the interface structure of functionally gradient materials is studied in a stainless steel-copper composite fabricated using a wire-feed electron beam technology. A distinct boundary is observed between the two materials, with the two-phase transition regions formed on both sides of the interface. The mechanical tests demonstrate an important role of the interface orientation during the plastic deformation development under uniaxial tensile loading. In the case of the longitudinal and diagonal interfaces, copper and steel simultaneously undergo plastic deformation. The fracture surface also reveals the presence of heterogeneous regions. In the orthogonal interface, necking and subsequent rupture occur in milder copper. However, its mechanical properties are found to be better compared to those of the additively grown copper.