Carlo Adamoli
Nickel-Beryllium alloy

Pagina 6

[Indice]

It is thus absolutely necessary, in order to obtain an efficient improvement of the alloy, to find a method which reduces the primary heterogeneousnesses between the hardening grains to minimum proportions and according to the present invention I have found for the first time that certain substances introduced into the nickel-beryllium alloys in comparatively small proportions, which should be never higher than predetermined maxima, have the property to of reducing the heterogeneousness of the interpositions between the hardening constituents by promoting at the moment of the solidification of the alloy their distribution and their solubilization in the granular mass in a perfect manner. It is well known, indeed, that the cohesion force between metals and their saturated solution is the higher the smaller the breaks of continuity between the crystals are, as results from the following equation: where d is the cohesion force, A the density and N the molecular weight of the solid body, S the normal solubility and Sw the solubility of the particles the radius of which is r.       As regards the substance which is introduced into the alloy as solubilizing and homogenizing substance, it is advisable not to lose sight of the fact that its specific action consists in annihilating or reducing in every way the surface deformations of the hardening constituents; the possibility for this action to appear is limited by the quantity of additional substance which is introduced into the alloy and which is always in small proportions. If the said quantity of introduced substance were increased above a certain maximum, the action would be altered in an essential manner; then hardening bodies are formed which are distinct from the Ni-Be constituents and which, on their side, show the same inconveniences which are due to fine heterogeneous interpositions. The method of improvement does not attain to its purpose and alloys are obtained which are always interior to the ternary alloy which is described later on and which contains the third element in the reduced proportions.

[Pagina Precedente] - [Indice] - [Pagina Successiva]