Classifications

• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C21/00—Alloys based on aluminium
  • C22C21/02—Alloys based on aluminium with silicon as the next major constituent

Definitions

• Patented May l, 1923 Patented May l, 1923.
• One object is to provide an alloy of this type having improved physical properties, especially tensile strength and ductility, and
• a further object is to provide a method of producing such alloys. 4 I
• he invention is based primarily upon my discovery that the addition to silicon aluminum alloys of certain metalloidsysuch as antimony or bismuth, has a marked beneficial effect upon their properties, particularly when the alloy is rapidly, cooled to complete solidification.
• a silicon-aluminum alloy is first. prepared in which a substantial amount of silicon is present. Silicon in small amounts, usually less than 1.0%, appears in most commercial aluminum as an impurity.
• the desirable properties of silicon-aluminum alldys, such for example as their low casting shrinkage, become usefully apparent only when the silicon is present in substantial amounts, say above about 3.0%, and it is alloys containing above about this percentage of silicon that are contemplated in this specification and claims as alloys containing a substantial amount of silicon.
• the amount of silicon present may vary from about 3.0 to 15.0%,- although'the best results are usually obtained When the silicon content is from about 8.0 to 13.0%.
• C The silicon-, aluminum alloy may be prepared, 'for example by stirring metallic silicon in molten aluminum at. a temperature of about 750 to 800 ,0. a
• bismuth or antimony are added, preferably in a finely divided form, and thoroughly incorporated by stirring. It is advantageous to pulverize the antimony or bismuth to about 20 mesh, and to introduce them into the molten silicon-aluminum alloy by sifting over the clean surface of the alloy. The reason for this is that the density of these metall'oids is so high that they tend to sink rapidly to the bottom of the crucible, and thereafter it is difficult to thoroughly incorporate them into the specifically lighter silicon-aluminum alloy. If, however, they are reduced to small particles before introduction, thorough mixing is much more readily accomplished, particularly in the case of bismuth which'has a' limlted solubility in aluminum.
• antimony or bismuth may be added up to a content of about 1.5%" or more but the best results are secured with 0.5to 1.0% of either. These elements remain in the alloy so that the alloy may be cast at any convenient time after the incorporation of bismuth or antimony.
• bismuth or antimony preferably copper or zinc which, in connection with" sihcon, alloys. 110
• the invention is not limited to, siliconaluminum alloys containing bismuth or antimony .alone, but includes alloys having additional elements, such for example as form a series of useful aluminum It is desirable that the iron content less than 0.6%, although in some cases as much as 1.5% or more of iron might be permissible when high ductility is not essential.
• antimony and bismuth together with phosphorus and arsenic, formsub-group b of the fifth group (Roscoe and Schorlemmer, 1913, edition, volume 2, page 910), andare usually ,spoken of as metalloids, while the elements of sub-ge'oup a, with the exception of nitrogen, are more metallic in ,character and are classed with the metals.
• Antimony and hismuth which are the metalloids of the fifth.
• I i 1.
• the improvement comprising incorporating in a finely divided state in the molten alloy a metalloid of the fifth group of the periodic system of the elements,
• the improvement com- 7 an aluminum alloy containing a substantial amount of s1l1con, the improvement comprising incorporating in the molten siliconof the fifth an atomic weight greater than 100,
• aluminum alloy a metalloid group'of the periodic system of the elements, having and causing rapid solidification of the molten alloy in a suitable mold.
• An aluminum base alloy containing .125 base alloy containin a from about 8.0 to 13.0% silicon, and an 15.0% silicon, and also containing. antimony. effective amount but not more than aboutr 14.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Mold Materials And Core Materials (AREA)
• Continuous Casting (AREA)

Priority Applications (4)

Applications Claiming Priority (1)

Publications (1)

Family

ID=24174256

Family Applications (1)

Country Status (4)

Cited By (4)

• 1922
  • 1922-03-18 US US544950A patent/US1453928A/en not_active Expired - Lifetime
• 1923
  • 1923-01-26 FR FR561448D patent/FR561448A/fr not_active Expired
  • 1923-02-02 CH CH104605D patent/CH104605A/fr unknown
  • 1923-02-14 GB GB4398/23A patent/GB195048A/en not_active Expired

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