Government of the United States of America, As Represented by the Secretary of Commerce

The United States Mint

The United States of America, As Represented by the Deparment of the Treasury

Tsineng Tony Ying

Carelyn E Campbell

Eric A Lass

Mark R Stoudt

Richard R Robidoux

Uvon Tolbert

A coinage cladding alloy for coinage includes nickel present in an amount from 5 wt. % to 7 wt. %, based on a total weight of the coinage cladding alloy; zinc present in an amount from 21 wt. % to 29 wt. %, based on the total weight of the coinage cladding alloy; manganese present in an amount from 12 wt. % to 16 wt. %, based on a total weight of the coinage cladding alloy; copper; an electrical conductivity from 2% International Annealed Copper Standard (IACS) to 3% IACS; and a color comprising a yellowness vector b* that is from 2 to 10, based on a CIE L*a*b* color space and determined in accordance with ASTM Standard E308-15 (2015).

Coinage cladding alloy and processing for making coinage cladding alloy

The metal alloy is a possible replacement for/alternative to cupronickel cladding material used on currently-circulating clad coins. In the preferred embodiment, the (steel) metal alloy cladding material comprises 73-77% iron, 22-26% nickel, 0.2-0.5% carbon, and 1-5% manganese. The cladding material has an International Annealed Copper Standard (IACS) conductivity of less than 2%, a permeability of approximately 1.0-1.1, and a hardness value of 50-70 HRC 15 T (Rockwell Hardness). In alternative embodiments, the steel alloy comprises a monolithic coin or a core that may be plated with other metals.

Metal alloy for coin production

A coinage alloy for coinage includes nickel present in an amount from 13 wt. % to 16 wt. %, based on a total weight of the coinage alloy; zinc present in an amount from 25 wt. % to 32 wt. %, based on the total weight of the coinage alloy; manganese present in an amount from 1 wt. % to 4 wt. %, based on a total weight of the coinage alloy; copper; an electrical conductivity from 5% International Annealed Copper Standard (IACS) to 6% IACS; and a color comprising a yellowness vector b* that is from 5 to 10, based on a CIE L*a*b* color space and determined in accordance with ASTM Standard E308-15 (2015).

Coinage alloy and processing for making coinage alloy

A primary alloy includes: nickel; copper; zinc; an electrical conductivity from 5.2% International Annealed Copper Standard (IACS) to 5.6% IACS measured in accordance with ASTM E1004-09 (2009); and a disordered crystalline phase wherein atoms of the nickel, cooper, and zinc are randomly arranged in the disordered crystalline phase at room temperature in a post-annealed state. A process for making the primary alloy includes heating a secondary alloy to a first temperature that is greater than or equal to an annealing temperature to form an annealing alloy, the secondary alloy including a secondary phase; and quenching, by cooling the annealing alloy from the first temperature to a second temperature that is less than the annealing temperature, under a condition effective to form the primary alloy including the disordered crystalline phase, wherein the disordered crystalline phase is different than the secondary phase of the secondary alloy.

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Silver Spring, MD, United States of America

Tsineng Tony Ying