Al–Pb–Zn Aluminum–Lead–Zinc system

Al–Pb–Zn Aluminum–Lead–Zinc system

608 most of the alloys the compound SbAl forms above 1 150 °K and tends to float on the liquid. Some antimony dissolves in the lead; at 1 000 °K the r...

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608 most of the alloys the compound SbAl forms above 1 150 °K and tends to float on the liquid. Some antimony dissolves in the lead; at 1 000 °K the ratio of antimony in the aluminum to that in the lead is only 2.22 [3]. The quasibinary section SbAl-Pb has a eutectic at 598 °K, approximately 99.0% Pb. The invariant reaction liq.A1-^Al + SbAl + liq.Pb is very close to the binary liq. A1 ^Al + liq.Pb (1.5% Pb, 931 °K); the eutectic liq.-^Al + SbAl + Pb very close to the liq.^Al+Pb (99.9% Pb 600 °K); and the eutectic liq.^SbAl + Sb + Pb very close to the liq.-^Pb + Sb (11% Sb, 525 °K) [2]. When lead dissolves in the AlSb compound, it replaces antimony atoms [4]. REFERENCES 1. 2. 3. 4.

C. R. A. Wright, Proc. Roy. Soc. London, 1894, 55, 130 G. W. Kasten, JIMMA 10, 386 G. Tammann, etc., CA 18, 3520 D. Shaw, JIMMA 31, 605

Al-Pb-Sn Aluminum-Lead-Tin system The miscibility gap in the aluminum-lead system shrinks with tin additions [1-5]. There is a ternary eutectic at 38.1% Pb, 61.7% Sn, 456 °K, very close to the binary lead-tin at 38.1% Pb, 61.9% Sn, 456.3 °K [4]. The solid solubility of both lead and tin in aluminum is less than 0.10% at the binary eutectic temperatures and therefore in practically all the alloys at the aluminum end the three phases Al, Pb, Sn are present. The preparation of aluminum-lead-tin alloys by preparing aluminum-tin alloys, melting out the eutectic and replacing it with molten lead is described [6]. REFERENCES 1. 2. 3. 4. 5. 6.

C. R. A. Wright, Proc. Roy. Soc, 1892/93, 52, 11 R. Lorenz, etc., JIM 43,490 M. H. Davies, JIMMA 20, 621 A. N. Campbell, etc., JIMMA 25, 11 J. Schmiedl, etc., WAA 6, 520064 M. L. Samuels, etc., JIMMA 10,48, 321

Al-Pb-Zn Aluminum—Lead-Zinc system The miscibility gaps in the aluminum-lead and lead-zinc systems join together in the ternary alloys, and cover most of the field. The only zones where liquid miscibility

609 exists are a small triangle at the lead end and a narrow band along the aluminum-zinc axis, which at its maximum width at approximately 40% zinc does not exceed 3% Pb [1]. The report that by the use of ultrasonic vibration alloys containing up to 10% Pb can be made homogeneous even after subsequent remelting [2] is open to doubt. REFERENCES 1. M. Dannenmuller, JIMMA 13, 293 2. W. Becker, JIMMA 11, 28

Al-S-Si, Al-Se-Si Aluminum-Sulfur-Silicon, Aluminum-Selenium-Silicon systems From the data reported [1] it would appear that at the aluminum end of the diagram the phases A12S3, Al and Si are in equilibrium and that SiS2 does not form until all (or most of) the aluminum is combined with sulfur. Sulfur and selenium additions are reported to reduce the segregation of primary silicon in hypereutectic aluminum-silicon alloys [2], but to have no appreciable modifying effect [3]. REFERENCES 1. E. J. Kohlmeyer, etc., JIMMA 20, 81 2. Anon., JIMMA 2, 147 3. S. Matsuo, etc., JIMMA 26, 279

Al-Sb-Si Aluminum-Antimony-Silicon system No ternary compound is formed; the phases in equilibrium at the aluminum corner are Al, Si, SbAl. A ternary eutectic, liq. —» Al + SbAl + Si, practically coincides with the binary Al-Si (12.5% Si, 850 °K) [1]. The location of the eutectic at 4.3% Sb, 9.2% Si, 848 °K is also reported [2], but such a high content of antimony is not supported by either the eutectic temperature of the microstructures shown. The solid solubilities of antimony and silicon in the ternary alloys should not differ substantially from those in the binary alloys. The solubilities of antimony and aluminum in silicon are limited. A quasibinary line Si-SbAl is indicated by a maximum of the viscosity at the line [3]. Antimony additions tend to reduce segregation of primary silicon in hypereutectic aluminum-silicon alloys [4, 5].