Copper phase diagram

The lead—copper phase diagram (1) is shown in Figure 9. Copper is an alloying element as well as an impurity in lead. The lead—copper system has a eutectic point at 0.06% copper and 326°C. In lead refining, the copper content can thus be reduced to about 0.08% merely by cooling. Further refining requites chemical treatment. The solubiUty of copper in lead decreases to about 0.005% at 0°C. 

Fig. 14. Aluminum-rich portion of alurninum—copper-phase diagram.

The aluminium-copper phase diagram is shown below. 

Fig. 20.41 (a) Silver-copper phase. diagram and (b) magnesium-tin phase diagram... 

Fig. 20.43 Aluminium-rich end of the aluminium-copper phase diagram...

The silver-copper phase diagram. Reprinted with permission of ASM International from L. A. Willey, Metals Handbook, vol. 8, 8th ed. (Materials Park, OH ASM, 1973), p. 259. All rights reserved, www.asminternational.org. 

FigMre 11.25 The aluminum-rich side of the aluminum-copper phase diagram. 

FIGURE 8.20 The gold-copper phase diagram (Courtesy of ASM International). 

Fig. 2. Liquidus of isotherms of gold-copper-silver alloys and phase diagrams of the binary constituents (83).

Tables 1 and 2, respectively, Hst the properties of manganese and its aHotropic forms. The a- and P-forms are brittle. The ductile y-form is unstable and quickly reverses to the a-form unless it is kept at low temperature. This form when quenched shows tensile strength 500 MPa (72,500 psi), yield strength 250 MPa (34,800 psi), elongation 40%, hardness 35 Rockwell C (see Hardness). The y-phase may be stabilized usiag small amounts of copper and nickel. Additional compilations of properties and phase diagrams are given ia References 1 and 2.

Phase diagrams have been measured for almost any alloy system you are likely to meet copper-nickel, copper-zinc, gold-platinum, or even water-antifreeze. Some... 

Fig. 3.6. (a) The copper-nickel diagram is a good deal simpler than the lead-tin one, largely because copper and nickel are completely soluble in one another in the solid state. (b) The copper-zinc diagram is much more involved than the lead-tin one, largely because there are extra (intermediate) phases in between the end (terminal] phases. However, it is still an assembly of single-phase and two-phase fields. 

The phase diagram for the copper-antimony system is shown on the next page. The phase diagram contains the intermetallic compound marked "X" on the diagram. Determine the chemical formula of this compound. The atomic weights of copper and antimony are 63.54 and 121.75 respectively. 

The copper-antimony phase diagram contains two eutectic reactions and one eutectoid reaction. For each reaction ... 

When the phase diagram for an alloy has the shape shown in Fig. 10.3 (a solid solubility that decreases markedly as the temperature falls), then the potential for age (or precipitation) hardening exists. The classic example is the Duralumins, or 2000 series aluminium alloys, which contain about 4% copper. 

Figure A1.19 shows the phase diagram for the copper-zinc system. It is more complicated than you have seen so far, but all the same rules apply. The Greek letters (conventionally) identify the single-phase fields. 

The copper-zinc system (which includes brasses) has one eutectoid reaction. Mark the eutectoid point on the phase diagram (Fig. A 1.38). 

Two phase diagrams are available for lithium-copper systems. No intermetallic phases were found, but LiCu4 was later observed. Substantial solid solubility of lithium in copper approaching 20 at% at the melting point of Li has been observed. 

No phase diagram is available for the sodium-copper system. 

No phase diagram is available for the potassium-copper or potassium-silver systems. A diagram for the potassium-gold system shows the existence of four intermediate phases but later work shows that the phase identified as KAU4 1 diagram is in fact KAuj. 

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