SECTION C + pre-plated upset balnk drawing.doc

SECTION C

STATEMENT OF WORK

C.1

GENERAL SCOPE

The United States Mint has a requirement for Circulating and Un-circulated copper-plated zinc (CPZ) one-cent planchets to be delivered to the Philadelphia and Denver Mints. Also included in this requirement is Proof CPZ one-cent planchets for the San Francisco Mint. CPZ planchets shall be delivered in accordance with the requirements, terms, conditions, and specifications set forth herein.

C.2

CPZ PLANCHET SPECIFICATIONS

C.2.1 Zinc Alloy Blanks (Prior to Plating)

Upset Configuration

As developed using tooling manufactured per

Drawing (Attachment C-1)

Hardness

Rockwell HR15T 67 ±5 (See Section E-3)

Tensile Strength

186 ± 21 MPa with grain (Reference only)

Surface Condition Free from clearly visible cracks, porosity; roll marks, deep scratches and inclusions

C.2.1.1

Microstructure

Well-defined grains with secondary (epsilon) phase precipitated primarily in grain boundaries. Grain size – 0.025 mm maximum utilizing measurements made in accordance with ASTM E-112 measured on a surface traverse to rolling direction.

C.2.1.2

Chemical Requirements of Pre-Plated Blanks

Core Copper

0.70% - 0.90% by weight

Lead

0.02% by weight maximum

Cadmium

Titanium

Iron

0.01% by weight maximum

Aluminum

0.005% by weight maximum

Zinc* by difference

*Note: Zinc is from Special High Grade Electrolytic slab per ASTM-B6-03.

C.2.2 Zinc Alloy Barrel Electroplated with Copper anodes

C.2.2.1

Plated Blank Dimensions of STANDARD CPZ PLANCHETS

Weight (individual blank)

2.50 grams ± 0.16 grams

Plated Diameter

18.75 mm ± 0.05 mm

Plated Gauge

1.255 mm ± 0.043 mm

(Preferred tolerance ± 0.030 mm)

Plating Thickness

0.008 mm + 0.017 mm/-0.003 mm

Upset Configuration

Same as pre-plated (C.2.1)

Upset Edge Thickness

1.461 mm ± 0.076 mm

Overall Thickness

1.626 mm maximum

“A” Dimension on Upset

0.64 mm ± 0.05 mm

“B” Dimension on Upset

1.27 mm + 0.13 mm/-0.00 mm

The grand average on an x-bar chart of the plated blank weights for each three-month period or part thereof, shall be at the target specification of 2.500 grams with incentives and penalties as described in Section E.

C.2.2.2

Plated Blank Dimensions for PROOF CPZ PLANCHETS Weight

2.60 grams ± 0.16 grams

18.87 mm ± 0.08 mm

1.27 mm ± 0.069 mm

0.0173 mm + 0.0081 mm/- 0.0046 mm

Surface Roughness

0.45(m max. Arith. Avg

C.2.2.3

Plated Blank Dimensions for UN-CIRCULATED CPZ PLANCHETS

Weight

2.58 grams ± 0.13 grams

18.77 mm ± 0.08 mm

1.27 mm ±0.064 mm

0.0173 mm + 0.0081 mm/-0.0046 mm

C.2.2.4

Plating

The copper plating shall conform to the Specifications for electro-deposited copper SAE-AMS-2418F, except as noted.

C.2.2.5

Thickness

Nominal plating thickness shall be measured using the Coulometric Method specified by ASTM B-504-90 or other methods if it can be demonstrated that the uncertainty of the method is less than 10%. Each sample found to contain between 4.57 (m and 5.59 (m (12.20 (m and 13.20 (m for proof and un-circulated) of copper plating should be run in triplicate, with the average rounded to two places and so reported. The x-ray method, developed by the U.S. Mint is an acceptable method for measuring plating thickness. The optical method, i.e., measuring the plating thickness of the cross section of a blank with a Filar microscope or other optical devices, shall be the primary standard for calibration of the coulometric and x-ray methods.

C.2.2.6

Chemical Requirements of Plated Planchets

Copper

2.50% by weight

Lead

Cadmium

Titanium

Iron

0.01% by weight maximum

Aluminum

0.005% by weight maximum

Zinc by difference

C.2.2.7

Materials

The base metals shall be as described in Section C.3.1 herein. The Contractor shall furnish the zinc from Special High Grade Electrolytic slab per ASTM-B6-87-E 1, and copper anodes used for electroplating and conform to Commercial Item Description A-A-51144, Type I, and Type II oxygen free copper.

C.2.2.8

Process

Blanks shall be subject to such cleaning, pickling and plating procedures as necessary to yield the coating specified. To minimize diffusion, apply only as much heat (less than 120° C) as is necessary to dry blanks without water staining.

C.2.2.9

Surface Condition

The plating shall be smooth, fine grained, adherent and free of visible blisters, pits, scales, nodules and uncoated areas, and shall not be stained or discolored. The protective coating resulting from the anti-tarnish treatment shall be non-toxic. See clause E.4 Defects for more detail.

C.2.2.10 Brightness Samples showing a range of finishes shall be furnished to the U.S. Mint for approval. These samples shall serve as criteria for acceptance of subsequent shipments (see First Article Samples, F- 12.). Upon acceptance of samples, subsequent shipments will be accepted on the same basis as samples.

C.2.2.11 Adhesion The adhesion of the plating shall be such that it does not show separation from the base metal at the interface when subjected to the bend test specified by paragraph 3.1 of ASTM B-571-91.

C.3

RAW METAL REQUIREMENTS

The Contractor shall acquire and supply all metal (copper and zinc) required for the fabrication of the Mint’s orders. The Mint shall purchase 100% of the weight of the blanks and pay metal price and premium under the prices in Section B at the time of shipment, B.X.D Metal Acquisition Prices. The Contractor shall supplement the scrap returned under Sections B.X.E., with virgin raw metals as necessary. The nominal percentages of 97.5 percent SHG Zinc and 2.5% Copper will be used for metal requirements calculations.

C.3.1 Virgin Metal Specifications

The specifications for the acquired virgin material are:

C.3.1.1

COPPER

C.3.1.1.a

ELECTROLYTIC COPPER

Electrolytic copper, full plate cathode in conformance with ASTM B115‑00 Grade #1, classified as "CATH" in ASTM B224‑98.

OR

C.3.1.1.b

ELECTROWON COPPER

Electrowon copper, cathode in conformance with ASTM B115-00 Grade #1, classified as "CATH" in ASTM B224-98.

C.3.2

ZINC

C.3.2.1.a

SPECIAL HIGH GRADE ZINC

Special High Grade (SHG) ZINC in conformance with ASTM B6‑03.

C.3.2.2.

ASTM SPECIFICATIONS

Copies of ASTM specifications may be obtained by writing to:

American Society for Testing and Materials

1916 Race Street

Philadelphia, PA 19103

Telephone No.: (215) 299-5585 www.astm.org

C.3.3

CERTIFICATE OF ANALYSIS

"CERTIFICATE OF ANALYSIS” for each incoming shipment should be available for Government review upon request.

C.3.4

ALLOWABLE SOURCES FOR RAW METALS

The Contractor shall acquire raw copper and zinc from sources on the following list in accordance with the Trade Agreements Act.

Antigua and Barbuda

Aruba

Austria

Bahamas

Bangladesh

Barbados

Belgium

Belize

Benin

Bhutan

Botswana

British Virgin Islands

Burkina Faso

Burundi

Canada

Cape Verde

Chad

Central African Republic

Costa Rica

Denmark

Dijbouti

Dominica

Dominican Republic

El Salvador

Equatorial Guinea

Finland

France

Gambia

Germany

Greece

Grenada

Guatemala

Guinea

Guinea-Bissau

Guyana

Haiti

Honduras

Hong Kong

Ireland

Israel

Italy

Jamaica

Japan

Kiribati

Lesotho

Liechtenstein

Luxembourg

Malawi

Maldives

Mali

Mexico

Montserrat

Mozambique

Nepal

Netherlands

Netherlands Antilles

Nicaragua

Niger

Norway

Panama

Portugal

Republic of Korea

Rwanda

Sao Tome and Principe

Sierra Leone

Singapore

Somalia

Spain

St. Kitts and Nevis

St. Lucia

St. Vincent and the Grenadines

Sweden

Switzerland

Tanzania U.R.

Togo

Trinidad and Tobago

Tuvalu

Uganda

United Kingdom

United States

Vanuatu

Western Samoa

Yemen

[END OF SECTION C]

Pre-Plated Upset Penny Blank