On the effectiveness of Ni alloy-bronze composite lattice structures used in slide bearings operated under heavy loads

Lattice structures with graded composition and microstructure in function of position allow for a smooth transition and due to their combination of multiple desirable features show great prospects in various applications. This study describes the characteristics of Ni alloy-bronze composite lattice structures (CLS) which can be used for manufacturing slide bearings intended for operation under heavy loads. The CLS were fabricated via directed energy deposition method on a substrate of AISI 1045 structural steel. The basic microstructural characteristics as well as microhardness were analyzed to study the features of composite structures depending on the speed of the laser beam as well as the laser spot step. Operational tests of the studied CLS were carried out under different loads and lubrication conditions. It was confirmed that the CLS wear resistance is 5–12 times higher under dry friction conditions and ∼65 times higher under mixed lubrication conditions as compared to the initial Ni alloy and bronze. It was claimed that CLS tested and formed using modern directed energy deposition technology exhibit improved material and tribological characteristics. These results are important both from the standpoint of practical applications and future research.