Copper-nickel-tin alloy with high toughness
AssigneeMaterion Corporation
InventorsW. Raymond Cribb, Chad A. Finkbeiner, Fritz C. Grensing
Life of this patent
Estimating the term…
Abstract
A spinodal copper-nickel-tin alloy with a combination of improved impact strength, yield strength, and ductility is disclosed. The alloy is formed by process treatment steps including solution annealing, cold working and spinodal hardening. These include such processes as a first heat treatment/homogenization step followed by hot working, solution annealing, cold working, and a second heat treatment/spinodally hardening step. The spinodal alloys so produced are useful for applications demanding enhanced strength and ductility such as for pipes and tubes used in the oil and gas industry.
Claims20
A spinodal copper-nickel-tin alloy having a 0.2% offset yield strength of at least 110 ksi, an impact toughness of at least 12 foot-pounds when measured according to ASTM E23, V notch at room temperature, and an ultimate tensile strength of at least 120 ksi, and a minimum elongation of 20%.
A spinodal copper-nickel-tin alloy produced by a process comprising:
- casting a copper-nickel-tin alloy;
- homogenizing the alloy;
- hot working the homogenized alloy to obtain a reduction ratio which is a minimum of about 5:1;
- solution annealing the hot worked alloy at a temperature of from about 1470° F. to about 1650° F.;
- cold working the solution annealed alloy until a reduction of area of from about 15% to about 80% occurs in the alloy;
- and
- spinodally hardening the alloy after the cold working to produce the spinodal alloy;
- wherein the spinodal alloy has a 0.2% offset yield strength of at least 110 ksi, an impact toughness of at least 12 foot-pounds when measured according to ASTM E23, V notch at room temperature, and an ultimate tensile strength of at least 120 ksi, and a minimum elongation of 20%.
A spinodal copper-nickel-tin alloy produced by a method comprising:
- solution annealing a copper-nickel-tin alloy wherein the solution annealing occurs at a temperature of from about 1475° F. to about 1650° F. and for a time of from about 0.5 hours to about 6 hours;
- cold working the solution annealed alloy, wherein the cold working results in a reduction of area in the alloy of from about 15% to about 80%;
- and
- spinodally hardening the alloy after cold working, wherein the spinodal hardening occurs at a temperature of from about 500° F. to about 675° F. and for a time of from about 0.5 hours to about 8 hours.
Dependencies are inferred from the claim text.