The density of metallic materials, along with strength and
corrosion-resistance, is one of the main physical characteristics. This
property is critical for nickel alloys, which are widely used in space
and aeronautics, where it is extremely important to minimize the mass of
each part. When developing new types of the alloys, it is essential to
have a reliable and accurate method for estimating density.
Unfortunately, no unified method for calculating the density has yet
been proposed, except several regression models that give more or less
accurate results. In this paper, we analyze and critically evaluate the
available approaches, and provide a group of advanced analytical
equations that accurately calculate the density of a nickel alloy based
on its chemical composition. The method takes into account the spatial
fcc structure of the alloys, the molar mass and molar volume of the
alloying elements, as well as, the behavior of light ligands. We verify
the accuracy of the equation based on real density and chemistry data
for 69 nickel alloys. Using all equations, we calculate the density and
compare the calculated data with real values. Comparison of the results
shows that the proposed method provides the best accuracy of all those
considered. The RMSE between the calculated values and the real ones is
about 0.07. The error of the regression methods is 0.5 at best. Thus,
the proposed approach increases the accuracy of calculating the density
of nickel alloys by about an order of magnitude, while significantly
simplifying it.