Metallurgy; an introduction to the study of physical metallurgy . alloys of copper,viz., those with tin. The constitutional diagram of thissystem has been very carefully worked out by Heycock andNeville (^) in a classical research, but their diagram wasadmittedly incomplete, and it has to a certain extent beenmodified by the subsequent work of Shepherd and Blough Q^),and of GioUitti i^\ Even now it is doubtful whether theintricacies of this complex system have been completely workedout. The diagram as given in Fig. 57 also embodies modifica-tions suggested by Hoyt (^), but our discussion of th
Metallurgy; an introduction to the study of physical metallurgy . alloys of copper,viz., those with tin. The constitutional diagram of thissystem has been very carefully worked out by Heycock andNeville (^) in a classical research, but their diagram wasadmittedly incomplete, and it has to a certain extent beenmodified by the subsequent work of Shepherd and Blough Q^),and of GioUitti i^\ Even now it is doubtful whether theintricacies of this complex system have been completely workedout. The diagram as given in Fig. 57 also embodies modifica-tions suggested by Hoyt (^), but our discussion of the alloysmust again be confined to those near the copper end of theseries, which are the most important for all practical purposes. TYPICAL ALLOY SYSTEMS 14T These may be taken a» having a tin-content of lesa than20 per cent. In these alloys, according to the diagram, we shall only meetwith three constituents, viz., those denoted by a, fi, and very complex changes uridergone by the alloys rangingfrom 20 to 40 per cent, of tin do not extend to the range of. 0Cti 80 30 40 50 60 Composition. Pig. 57.—Constitutional Diagram of the Tin-Copper Alloys 30 igp%Sn On. bronzes ordinarily employed for engineering purposes. Thetransformation which occurs along the Une PQ is, however,of great imporance in regard to all bronzes containing more than12 per cent, of tin. The micro-structure of tin-copper alloys containing less than10 per cent, of tin is very simple and exactly similar to thatof the corresponding zinc-copper alloys, being that of a simple l2 148 STUDY OF PHYSICAL METALLURGY solid solution of a tin-copper compound in copper. Whenrapidly solidified these alloys exhibit the dendritic structurecharacteristic of sohd solutions which have not attainedequilibrium, but slower freezing, or subsequent annealing at ahigh temperature, obliterates the differences of compositionwhich exist between the cores and the peripheral regions ofthe crystals, and results in the formation of the
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectmetals, bookyear1922
