For instance, if, according to the present invention, molybdenum is introduced as solubilizing and homogenizing substance into nickel-beryllium alloys, the ternary alloys Ni-Be-Mo for which the maximum physico-mechanical characteristics are obtained are those which are indicated by the hachured part A of the diagram shown in Figure 1 of the accompanying drawings and which relates to the Ni-Be-Mo system. It may be seen that the said alloys are those which for a beryllium content varying approximately from 1.4 to 1.7% contain molybdenum in a quantity varying from 0.3 to about 1%, the remainder being substantially all nickel.
This action indicated for molybdenum for beryllium alloys with a nickel basis has also been verified for the following substances which are diffusing, solubilizing and homogenizing substances, i. e. tungsten, tantalum, chromium and zirconium. The following are, only by way of example, the iimit proportions between which it is advisable to introduce those different substances intò the nickel-beryllium alloys generally containing from 1.4 to 1.7% of beryllium (the remainder being substantially ali nickel), in order to obtain the characteristic results of the present invention.
Molybdenum - From 0.3 up to 1%
Tungsten - From traces up to 3%
Tantalum - From traces up to 2%
Chromium - From traces up to 5%
Zirconium - From 0.3 up to 1%
The so obtained alloys are subjected to a thermal treatment which preferably comprises heating to a temperature of 1000 to 1020° C. during 30 to 45 minutes followed by a rapid cooling, for instance in water, and then annealing at a temperature of about 485° C. to 500° C. during 6 to J.5 hours to produce the re-precipitation of the hardening constituent diffused in the basic metal, i. e. the nickel, this complete treatment being repeated if desired.
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