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Single crystals of lead with either thallium, indium, bismuth, cadmium, mercury or antimony were tested in tension in liquid air. The critical resolved shear stress t0 increases linearly with increasing solute content c in a limited concentration range. The increase ?t0/?C is lowest for lead-thallium and highest for lead-antimony. When log ?t0/?C is plotted against log (sf + elf) where sf*[(d1)Pb - (d1)sol/(d1)Pb]10Pb, d1 being the closest distance of approach, and elf = SEn, SEn being the sum of the electronegativities of solvent and solute, a straight line of slope 2 results. A similar result is obtained with data from the literature for single crystals of copper alloys and of magnesium alloys. However in these cases a different size factor has to be used.

The magnetic susceptibilities and single crystalline elastic constants of lead-indium alloys have been measured in the composition range 0 to 20 at.% indium. Comparison of these data with the data from lead-thallium alloys shows that, in the composition range 0 to 7 at.% solute, the solutes serve primarily to deplete the valence electron concentrations with band structures which are essentially the same as that of pure lead. At higher solute concentrations, those parameters of the lead-indium alloys which are controlled by the valence electron distributions diverge from values which would be expected from a simple lowering of the Fermi energy within the band structure of lead. Thus a rigid band approximation is valid at lower but not at higher indium concentrations in the lead-indium system. A qualitative correlation exists between the elastic anisotropy ratios and the stacking fault densities in both the lead-indium and lead-thallium alloy systems.

Three copper-gold single crystals containing 29.9 at. % gold and having the disordered, Cu3Au I and Cu3Au II structure respectively, were deformed in tension at room temperature, at dry ice temperature (just into the plastic region) and at liquid nitrogen temperature (until fracture) successively.