Copper-nickel-tin alloy, method for the production thereof and use thereof

Patent metadata

Field	Value
Publication number	US-11035024-B2
Application number	US-201716308204-A
Country	US
Kind code	B2
Filing date	Jun 27, 2017
Priority date	Jul 18, 2016
Publication date	Jun 15, 2021
Grant date	Jun 15, 2021

Abstract

A high-strength copper-nickel-tin alloy with excellent castability, hot workability and cold workability, high resistance to abrasive wear, adhesive wear and fretting wear and improved resistance to corrosion and stress relaxation stability, consisting of (in weight %): 2.0-10.0% Ni, 2.0-10.0% Sn, 0.01-1.5% Si, 0.002-0.45% B, 0.001-0.09% P, selectively up to a maximum of 2.0% Co, optionally also up to a maximum of 2.0% Zn, selectively up to a maximum of 0.25% Pb, the residue being copper and unavoidable impurities. The ratio Si/B of the element contents in wt. % of the elements silicon and boron is a minimum 0.4 and a maximum 8 such that the copper-nickel-tin alloy has Si-containing and B-containing phases and phases of the systems Ni—Si—B, Ni—B, Ni—P and Ni—Si, which significantly improve the processing properties and use properties of the alloy.

First claim

The invention claimed is:

1. A copper-nickel-tin alloy consisting of (in % by weight):
2.0% to 10.0% Ni,
2.0% to 10.0% Sn,
0.01% to 1.5% Si,
0.002% to 0.45% B,
0.001% to 0.09% P,
optionally up to a maximum of 2.0% Co,
optionally up to a maximum of 2.0% Zn,
optionally up to a maximum of 0.25% Pb,
the balance being copper and unavoidable impurities,
wherein
the Si/B ratio of the element contents in % by weight of the elements silicon and boron is a minimum of 0.4 and a maximum of 8;
the following microstructure constituents are present in the alloy after casting:

a) a Si-containing and P-containing metallic base composition having, based on the overall microstructure,
a1) up to 35% by volume of first phase constituents that can be reported by the empirical formula Cu h Ni k Sn m and have an (h+k)/m ratio of the element contents in atomic % of 2 to 6,
a2) up to 15% by volume of second phase constituents that can be reported by the empirical formula Cu p Ni r Sn s and have a (p+r)/s ratio of the element contents in atomic % of 10 to 15, and
a3) a balance of a solid copper solution;
b) phases which, based on the overall microstructure, are present
b1) at 0.01% to 10% by volume as Si-containing and B-containing phases,
b2) at 1% to 15% by volume as Ni—Si borides having the empirical formula Ni x Si 2 B with x=4 to 6,
b3) at 1% to 15% by volume as Ni borides,
b4) at 1% to 5% by volume as Ni phosphides, and
b5) at 1% to 5% by volume as Ni silicides in the microstructure, which are present individually and/or as addition compounds and/or mixed compounds and are ensheathed by tin and/or the first phase constituents and/or the second phase constituents;
in the course of casting the Si-containing and B-containing phases in the form of silicon borides, the Ni—Si borides and the Ni borides, Ni phosphides and Ni silicides that are present individually and/or as addition compounds and/or mixed compounds constitute seeds for uniform crystallization during the solidification/cooling of the melt, such that the first phase constituents and/or the second phase constituents are distributed uniformly in the microstructure in the form of islands and/or in the form of a mesh;
the Si-containing and B-containing phases that are in the form of boron silicates and/or boron phosphorus silicates, together with phosphorus silicates, assume the role of a wear-protecting and corrosion-protecting coating on semifinished materials and components of the alloy.

2. The copper-nickel-tin alloy as claimed in claim 1 , wherein the elements nickel and tin are each present at 3.0% to 9.0%.

3. The copper-nickel-tin alloy as claimed in claim 1 , wherein the element silicon is present at 0.05% to 0.9%.

4. The copper-nickel-tin alloy as claimed in claim 1 , wherein the element boron is present at 0.01% to 0.4%.

5. The copper-nickel-tin alloy as claimed in claim 1 , wherein the element phosphorus is present at 0.01% to 0.09%.

6. The copper-nickel-tin alloy as claimed in claim 1 , wherein the alloy is free of lead apart from any unavoidable impurities.

7. A copper-nickel-tin alloy consisting of (in % by weight):
2.0% to 10.0% Ni,
2.0% to 10.0% Sn,
0.01% to 1.5% Si,
0.002% to 0.45% B,
0.001% to 0.09% P,
optionally up to a maximum of 2.0% Co,
optionally up to a maximum of 2.0% Zn,
optionally up to a maximum of 0.25% Pb,
the balance being copper and unavoidable impurities,
wherein
the Si/B ratio of the element contents in % by weight of the elements silicon and boron is a minimum of 0.4 and a maximum of 8;
after further processing of the alloy by at least one annealing operation or by at least one hot forming operation and/or cold forming operation, as well as at least one annealing operation, the following microstructure constituents are present:

A) a metallic base composition having, based on the overall microstructure,
A1) up to 15% by volume of first phase constituents that can be reported by the empirical formula Cu n Ni k Sn m and have an (h+k)/m ratio of the element contents in atomic % of 2 to 6,
A2) up to 5% by volume of second phase constituents that can be reported by the empirical formula Cu p Ni r Sn s and have a (p+r)/s ratio of the element contents in atomic % of 10 to 15, and
A3) a balance of a solid copper solution;
B) phases which, based on the overall microstructure, are present,
B1) at 2% to 30% by volume as Si-containing and B-containing phases, Ni—Si borides having the empirical formula Ni x Si 2 B with x=4 to 6, as Ni borides, Ni phosphides and as Ni silicides in the microstructure, which are present individually and/or as addition compounds and/or mixed compounds and are ensheathed by precipitates of the (Cu, Ni)—Sn system,
B2) at up to 80% by volume as continuous precipitates of the (Cu, Ni)—Sn system in the microstructure, and
B3) at 2% to 30% by volume as Ni phosphides and Ni silicides in the microstructure that are present individually and/or as addition compounds and/or mixed compounds, are ensheathed by precipitates of the (Cu, Ni)—Sn system and have a size of less than 3 μm;
the Si-containing and B-containing phases that are in the form of silicon borides, the Ni—Si borides and the Ni borides, Ni phosphides and Ni silicides that are present individually and/or as addition compounds and/or mixed compounds constitute seeds for static and dynamic recrystallization of the microstructure during the further processing of the alloy, which enables the establishment of a uniform and fine-grain microstructure;
the Si-containing and B-containing phases that are in the form of boron silicates and/or boron phosphorus silicates, together with phosphorus silicates, assume the role of a wear-protecting and corrosion-protecting coating on semifinished materials and components of the alloy.

8. The copper-nickel-tin alloy as claimed in claim 7 , wherein the elements nickel and tin are each present at 3.0% to 9.0%.

9. The copper-nickel-tin alloy as claimed in claim 7 , wherein the element silicon is present at 0.05% to 0.9%.

10. The copper-nickel-tin alloy as claimed in claim 7 , wherein the element boron is present at 0.01% to 0.4%.

11. The copper-nickel-tin alloy as claimed in claim 7 , wherein the element phosphorus is present at 0.01% to 0.09%.

12. The copper-nickel-tin alloy as claimed in claim 7 , wherein the alloy is free of lead apart from any unavoidable impurities.

Assignees

• Wieland Werke Ag

Inventors

• Weber Kai

Classifications

• C22C1/1073

  Infiltration or casting under mechanical pressure, e.g. squeeze casting · CPC title

• C22C1/1036

  starting from a melt · CPC title

• C22C9/06 Primary

  with nickel or cobalt as the next major constituent · CPC title

• B22D11/004

  Copper alloys · CPC title

• C22F1/08

  of copper or alloys based thereon · CPC title