The mean curves for Brinell hardness shown in Figure 2 correspond to the two following allows:
Normal nickel-beryllium-molybdenum alloy (referred to in the diagram by the abbreviation "N. M.")
Be: between 1.4 and 1.6%.
Mo: between 0.3 and 0.5%.
Ni: the remainder.
Hard nickel-beryllium-molybdenum alloy (re-ferred to in the diagram by the abbreviation "N. M. D.")
Be: between 1.4 and 1.7%.
Mo: between 0.3 and 0.5%.
Ni: the remainder.
The variations in Brinell hardness (ordinates) are presented as a function of the temperature of heating before quenching (abcissae). These alloys should be preferably heated to 1000° C.-1020° C. for 45 minutes, quenched with water, then annealed at 485° C. for about 10 hours, in order to obtain harder alloys, or for 15 hours in order likewise to obtain greater tenacity.
The mean curves of hardness in Figures 2 and 3 apply respectively to the two alloys above with nickel as base, referred to by the abbreviations "N. M. D." and "N. M.'\ These curves give the variations in the hardness after annealing for different temperatures, as a function of the duration of annealing shown in hours H (abscissae).
Figure 4 relates solely to the alloy "N. M.”. The three curves in thin lines marked "A" illustrate the variations in percentage elongation A % for varying periods of annealing at the annealing temperatures marked on the curves. The five curves in heavy lines marked "R" show the variations in tensile strength R in hgs. per mm.2 with varying periods of annealing at the temperatures shown on the curves.
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