DEFSTAN 03-14/4(2008) : 2008

Foreword
SECTION 1 - INTRODUCTION
Overview
Type of Chromium Coatings
SECTION 2 - GENERAL REQUIREMENTS
1 Scope
2 Warning
3 Normative References
4 Abbreviations
5 Definitions
   5.1 Process Control Schedule
   5.2 Significant Surface
   5.3 Shot Peening
   5.4 Tensile Strength of Steels
6 Information to be Supplied to the Processor
7 Process Control
SECTION 3 - PROCESS REQUIREMENTS
8 Condition of Substrate
9 Chromium Electrodeposition Processes
10 Reclamation of Worn or Over-Machined Surfaces
11 Dimensional Tolerances
12 Thickness of Electrodeposit after Final Finishing
13 Machining and Grinding
SECTION 4 - ELECTRODEPOSITION ON FERROUS METALS
14 General
15 Stress Relief
16 Introduction of Surface Compressive Stresses
17 Preparation for Electrodeposition
   17.1 Initial cleaning
   17.2 Masking
   17.3 Application of undercoats
   17.4 Final cleaning
   17.5 Etching
   17.6 Rinsing
18 Electrodeposition of Chromium
19 Post-Electrodeposition Heat Treatment
SECTION 5 - ELECTRODEPOSITION ON ALUMINIUM AND ALUMINIUM ALLOYS
20 General
21 Preparation for Electrodeposition
22 Electrodeposition of Chromium
23 Post-Electrodeposition Heat Treatment
SECTION 6 - ELECTRODEPOSITION ON TITANIUM AND TITANIUM ALLOYS
24 General
25 Preparation for Electrodeposition
26 Electrodeposition of Chromium
27 Post-Electrodeposition Heat Treatment
SECTION 7 - ELECTRODEPOSITION ON OTHER METALS
28 General
29 Preparation for Electrodeposition
30 Electrodeposition of Chromium
31 Electrodeposition of Chromium on Chromium
SECTION 8 - INSPECTION AND TEST
32 Inspection and Testing
33 Visual Inspection
34 Thickness of Coating
35 Hardness
36 Adhesion
37 Freedom from Embrittlement
38 Corrosion Testing
39 Other Requirements
40 Treatment of Items Rejected during Final Inspection and Test
ANNEX A - GUIDANCE ON CHROMIUM ELECTRODEPOSITION FOR ENGINEERING
          PURPOSES
   A.1 Introduction
   A.2 Types of Hard Chromium Electrodeposition Process
        A.2.1 Standard (single catalyst) process
        A.2.2 Fluoride-containing, 'dual catalyst' process
        A.2.3 Proprietary, non-fluoride catalysts
        A.2.4 Summarising comments
   A.3 Other Types of Chromium Electrodeposit
        A.3.1 Porous chromium
        A.3.2 Crack free chromium.
   A.4 Corrosion Behaviour of Chromium-Electrodeposited
        Components
   A.5 Suitability for Chromium Electrodeposition
   A.6 Effect of Chromium Electrodeposition on Mechanical
        Integrity of Component
        A.6.1 Type-testing of chromium electrodeposited items
        A.6.2 New designs of items subject to dynamic loading
        A.6.3 Repair of items subject to dynamic loading
        A.6.4 Repair of items subject to static loading
   A.7 Selection of Basis Materials
   A.8 Mechanical Pre-Treatment of Items
        A.8.1 Mechanical preparation
        A.8.2 Surface finish
        A.8.3 Compressive Stresses
   A.9 Electrodeposition with Other metals on Areas not
        Chromium Electrodeposited
ANNEX B - CHROMIUM ELECTRODEPOSITION PROCESS
   B.1 Electrodeposition Solution for Standard Process
        (Single, Sulphate Catalyst)
   B.2 Anodes
   B.3 Operating Conditions
ANNEX C - THE ANALYSIS OF CHROMIUM ELECTRODEPOSITION SOLUTION
   C.1 Standard Electrodeposition Solution
        C.1.2 Chromic acid concentration
        C.1.3 Sulphuric acid concentration
        C.1.4 Iron concentration
        C.1.5 Trivalent chromium concentration
   C.2 Higher Speed Solutions
ANNEX D - POST ELECTRODEPOSITION TREATMENT FOR FERROUS METALS
ANNEX E - CHEMICAL METHODS OF STRIPPING CHROMIUM DEPOSITS
   E.1 Ferrous metals and Nickel Substrates
   E.2 Aluminium, Titanium and their Alloys
   E.3 Copper and Copper alloys
   E.4 Zinc and Zinc Alloys
ANNEX F - ADHESION TESTING
   F.1 Bend test
   F.2 Chisel test

Provides guidance for- and specifies the requirements for- the electrodepositiion of chromium for engineering purposes.