WO1996013617B1

WO1996013617B1 - Machineable aluminum alloys containing in and sn and process for producing the same

Info

Publication number: WO1996013617B1
Application number: PCT/US1995/014023
Authority: WO
Filing date: 1995-10-27
Publication date: 1996-06-20
Anticipated expiration: 1997-04-27

Abstract

Free-machining aluminum alloys are disclosed containing effective amounts of tin and indium. The tin and indium additions are especially adapted for use as free-machining constituents in aluminum alloys, such as AA2000 and AA6000 series aluminum alloys. The additions can be used in place of bismuth and lead in currently available free machining alloys. In alloys containing bismuth and tin, the indium can be used to replace the bismuth. A method of producing a free-machining aluminum alloy product also is described.

Claims

AMENDED CLAIMS[received by the International Bureau on 26 April 1996 (26.04.96); original claims 1-23 replaced by amended claims 1-18 (4 pages)]

1. A free-machining aluminum alloy comprising an aluminum alloy including an effective amount of tin and an effective amount of indium, the effective amounts of tin and indium being those amounts of tin and indium that when combined with each other and with other elements in the alloy form low melting point constituents that melt during a machining operation to facilitate formation of proper size machine chips for effective machining, the amount of tin and indium in the alloy ranging from 0.04 to 1.5 wt. % and the alloy having copper as a major alloying element.

2. The free-machining alloy of claim 1 wherein said tin and indium further comprise an eutectic ratio of tin to indium.

3. The free-machining alloy of claim 1 wherein said tin and indium further comprise a tin-rich ratio of tin to indium.

4. The free-machining alloy of claim 1 wherein said tin and indium range from 0.05 to 0.8 wt %.

5. The free-machining alloy of claim 1 wherein said indium ranges between 0.22 and 0.38 wt. % and said tin ranges between 0.20 and 0.52 wt. %.

6. The free-machining alloy of claim 1 wherein said tin and indium are substituted for a low melting point constituent containing lead.

7. A free-machining aluminum alloy comprising an aluminum alloy including an effective amount of tin and an effective amount of indium, the effective amounts of tin and indium being those amounts of tin and indium that when combined with each other and with other elements in the alloy form low melting point constituents that melt during a machining operation to facilitate formation of proper size machine chips for effective machining, the amount of tin and indium in the alloy ranging from 0.04 to 1.5 wt . % and the alloy having magnesium and silicon as major alloying elements .

8. A free-machining aluminum alloy comprising an aluminum alloy including an effective amount of tin and an effective amount of indium, the effective amounts of tin and indium being those amounts of tin and indium that when combined with each other and with other elements in the alloy form low melting point constituents that melt during a machining operation to facilitate formation of proper size machine chips for effective machining, said aluminum alloy consisting essentially in weight percent of: between 0.4 and 0.8% silicon; up to 0.7% iron; between 0.15 and 0.40% copper; up to 0.15% manganese; between 0.8 and 1.2 wt. % magnesium; between 0.04 and 0.35% chromium; up to 0.25% zinc; up to 0.15% titanium; between 0.05 and 1.5% indium; and between 0.05 and 1.5% tin; with the balance aluminum and inevitable impurities .

9. The free-machining alloy of claim 8 wherein said tin and indium are in a eutectic ratio.

10. The free-machining alloy of claim 8 wherein said tin and indium each range from 0.05 to 0.8 wt. %.

11. The free-machining alloy of claim 8 wherein said indium ranges between 0.22 and 0.38 wt . % and said tin ranges between 0.20 and 0.52 wt. %.

12. A free-machining aluminum alloy comprising an aluminum alloy including an effective amount of tin and an effective amount of indium, the effective amounts of tin and indium being those amounts of tin and indium that when combined with each other and with other elements in the alloy form low melting point constituents that melt during a machining operation to facilitate formation of proper size machine chips for effective machining, said alloy in weight percent consisting essentially of: between 0.05 and 1.5% indium; between 0.05 and 1.5% tin; up to 0.40 wt . % silicon; up to 0.70 wt. % iron; between 4.0 and 6.0 wt. % copper; up to 0.30 wt. % zinc; up to 0 . 15 wt . % titanium; 617 2 £ PCI7US95/14023

with the balance aluminum and inevitable impurities.

13. The free-machining alloy of claim 12 wherein said tin and indium each range from 0.05 to 0.8% wt .

14. The free-machining alloy of claim 13 wherein said indium ranges between 0.22 and 0.38 wt . % and said tin ranges between 0.20 and 0.52 wt. %.

15. The free-machining alloy of claim 1, wherein said alloy has greater than 0.10 wt. % indium.

16. The free-machining alloy of claim 7, wherein said alloy has greater than 0.10 wt. % indium.

17. The free-machining alloy of claim 8, wherein said alloy has greater than 0.10 wt. % indium.

18. The free-machining alloy of claim 12, wherein said alloy has greater than 0.10 wt. % indium.