Metallurgy; an introduction to the study of physical metallurgy . tial, however, as with a few points only it would not bepossible to distinguish between the soHd solution and the intermediate eutectiferous types. This is illustrateddiagrammatically in Fig. 40, where it is clearly shown how twodifferent types of curve may agree in fitting points representingonly a few determinations. The same remark also applies,by the way, to thermal and other data and, indeed, actualmistakes in laying down a constitutional diagram have beenmade in several instances owing to the fact that the I 1
Metallurgy; an introduction to the study of physical metallurgy . tial, however, as with a few points only it would not bepossible to distinguish between the soHd solution and the intermediate eutectiferous types. This is illustrateddiagrammatically in Fig. 40, where it is clearly shown how twodifferent types of curve may agree in fitting points representingonly a few determinations. The same remark also applies,by the way, to thermal and other data and, indeed, actualmistakes in laying down a constitutional diagram have beenmade in several instances owing to the fact that the I 114 STUDY OF PHYSICAL METALLURGY points werefeatures. too far apart to indicate all the important In the case of more complex alloys, containing either definitecompounds or series of solid solutions which are based upondefinite compounds, the conductivity curve assumes morecomplex shapes. In these alloys new solid constituents maketheir appearance at various points along the axis of concentra-tion, and corresponding to these sudden changes in structure iiCu( Cu 20 30 40 50 66 70 eo SO wom Composition. Sb Fig. 41.—Curve of Speoiflo Conductivity for the Alloys of Copper andAntimony, showing Discontinuities corresponding to definiteCompounds. and constitution, the curve of conductivities generally, butnot always, changes its direction. As a rule, therefore, achange of direction in the conductivity curve may be taken asindicating that one has passed into a new field or region of theequilibrium diagram, but it is not safe to conclude that, becausethe conductivity curve shows no deflection, no fine of the dia-gram can have been crossed. Definite inter-metallic com-pounds resemble pure metals in their conducting propertiesto some extent—, they conduct better than either mixtures PHYSICAL PROPERTIES OF ALLOYS 115 or solid fiolutions containing them—but they do not conductnearly so well as their component pure metals, nor does theirconductivity bear any numerical relation
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectmetals, bookyear1922
