A06 HIF Specifications Crome Plate (HIFC03D).pdf

HIF-C-03D

09-07-10

U.S. GEOLOGICAL SURVEY

WATER RESOURCES DIVISION

HYDROLOGIC INSTRUMENTATION FACILITY

ENGINEERING SPECIFICATION

FOR

CHROME PLATE, BRIGHT OVER NICKEL

This specification covers the electro-deposition of bright chromium over a bright nickel or bright nickel and copper pre-plate. This coating is intended primarily for decorative purposes, but to also offer moderate protection against corrosion similar to ASTM B 456 Service Condition SC2.

1. Specifications referenced in this document:

ASTM B 456:

Standard Specification for Electrodeposited Coatings of Copper Plus Nickel Plus Chromium and Nickel Plus Chromium

2. REQUIREMENTS:

A. Parts to be plated in accordance with this specification shall have a surface finish equal to or better than the surface finish required after plating.

B. Refer to each part drawing for surfaces requiring preparation prior to plating. Parts which show excessive surface defects after normal surface preparation shall be referred to the Hydrologic Instrumentation Facility for approval before plating.

C. Basis Metals, Plating Metals, and Minimum Plating Thickness:

Basis Metal (Metal to Which Plating is to be Applied) Aluminum Brass Steel Zinc Minimum Plating Thickness, Inches (micrometers, µm)

P la tin g

M et al Copper Zincate or

“Alstan 70” 1 Copper

Strike Only .0002 2

(5 µm) .0002 (5 µm)

Bright Nickel

.0008 (20 µm)

.0004 (10 µm)

.0008 (20 µm)

.0008 (20 µm)

Chrome .00001 (.25 µm)

.00001 (.25 µm)

.00001 (.25 µm)

.00001 (.25 µm)

HIF-C-03D

09-07-10

1 When applying nickel plating to aluminum basis metal, the copper pre-plate is replaced by the ‘Zincate’ or ‘Alstan 70’ treatment.

2 The plating of copper on steel is optional. It may be used when, in the opinion of the plater, it is required for adherence.

D. The significant surfaces of the electroplated article shall be free of clearly visible plating defects such as blisters, pits, roughness, cracks, and uncoated areas, and shall not be stained or discolored. On articles where a visible contact mark is unavoidable, consult the Hydrologic Instrumentation Facility regarding placement. The electroplated article shall be clean and free from damage.

E. Dimensions on the drawings for parts to be plated denote the size before plating, except that dimensions labeled “After Plating” apply to the parts after plating.

3. INSPECTION:

The plating shall be tested for thickness and adherence in accordance with ASTM Specification B 456.