Structure and properties of the composite material based on heat-resisting VKNA-4U alloy with oxide stiffening fillers, designed for additive manufacturing technologies of power fasteners for gas turbine engines (GTE)

The influence of the structure and concentration of the stiffening component on the physicomechanical properties of the heat-resisting intermetallic alloy VKNA-4U was investigated. The dependence of the strength properties of the alloy on the composition and ratio of the hardeners α-Al₂O₃, Y₂O₃, HfO₂, ZrO₂ was experimentally determined. Using scanning electron microscopy (SEM), it was found that when the alloy is reinforced with hafnium, yttrium and aluminum oxides, the dispersed hardener does not dissolve in the matrix. These compositions are considered as the most promising for the stiffening of VKNA-4U alloy.

It is shown in this paper that the required content of the oxide reinforcing filler in the VKNA-4U matrix is 2%, at which a balance is reached between the maximum value of strength and ductility. In the future, VKNA-4U powder composition mechanically alloyed with β-Al₂O₃, Y₂O₃, HfO₂ oxides can be used as a building material for additive synthesis technologies for power fasteners of gas turbine engines (GTE). (paper)