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Most Common Hard Chrome Plating Specifications

This information provides a basic overview of the most common hard chrome plating specifications including a breakdown of classes, appearance, finish, and types. For full details on each of these specifications, please visit SAE International, ASTM International, and Defense Standardization Program.

SAE Aerospace Material Specifications (AMS)

SAE is an organization that develops standards for professionals in the engineering fields relating to transport like aerospace, automotive and commercial vehicles.

AMS2460, Plating, Chromium

This specification covers the requirements for electrodeposited chromium plating.


Electrodeposited chromium plating shall be one of the following classes:

  • Class 1: Corrosion protective plating
  • Class 2: Engineering plating


Class 1 plating shall have one of the following types of lusters, as specified:

  • Type I: Bright finish
  • Type II: Satin finish

The current revision of AMS2460 is Rev. B (AMS2460B)

SAE AMS-QQ-C-320B has been superseded by SAE AMS2460

AMS2406, Chromium Plating, Hard

This specification covers the requirements for electrodeposited hard chromium plate.

There are no class, appearance, or type specifications. This plating has been used typically on parts for increasing abrasion resistance, increasing tool and die life, maintaining accuracy of gauges, and reconditioning worn or undersized parts, but usage is not limited to such applications.

The current revision of AMS2406 is Rev. P (AMS2406P)

American Society for Testing and Materials (ASTM)

ASTM is an organization that develops consensus technical standards for a wide range of materials, products, systems, and services.

ASTM B650, Standard Specification for Electrodeposited Engineering Chromium Coatings on Ferrous Substrates

This specification covers the requirements for electrodeposited chromium coatings (sometimes referred to as functional or hard chromium) applied to ferrous alloy substrates for engineering applications, particularly for increasing wear, abrasion, fretting, and corrosion resistance; for reducing galling or seizing, and static and kinetic friction; and for building up undersize or worn parts.


Electrodeposited chromium coatings in accordance with this specification are classified by the thickness of the coating as follows:

  • Class 1: 2.5 to 25µm
  • Class 2: >25µm

The current revision of ASTM B650 is Rev. 95 (ASTM B650-95)

Department of Defense Standard

The DoD standard, also known as military standard, MIL-SPEC, or MIL-STD, is used to ensure goods meet certain requirements likes reliability, compatibility, total cost of ownership (TCO), and other defense related objectives.

MIL-STD-1501, Chromium Plating, Low Embrittlement, Electro-Deposition

This standard covers the engineering requirements for electro-deposition of hard chromium on high strength steel substrates and the properties of deposit.


Chromium plating covered by this standard should be the following:

  • Class 1: Crack free
  • Class 2: Limited cracking allowed
  • Class 3: Moderate cracking allowed


Chrome plating covered by this standard should be of the following:

  • Type I: Plated to specified dimensions
  • Type II: Processed to specified dimensions after plating

The current revision of MIL-STD-1501 is Rev. F (MIL-STD-1501F)

MIL-C-23422 | MIL-DTL-23422, Chromium Plating, Electrodeposited

This specification covers the requirements for electrodeposited chromium plate for applications where high quality hard chromium plate is required.


Chromium plate shall be of the following classes, as specified:

  • Class 1: Anti-wear, thickness as specified
  • Class 2: Anti-galling, thinness 0.0002 to 0.0006 inch


Chromium plate shall be of the following finishes, as specified:

  • As-plated
  • Ground
  • Honed


Types of basis metal to be plated:

  • Type I: Austenitic stainless steel
  • Type II: Martensitic stainless steel
  • Type III: Nickel base alloys
  • Type IV: Carbon and low alloy steels
  • Type V: Composite plate of others as specified
  • Type VI: Precipitation hardening stainless steel
The current revision of MIL-C-23422 is Rev. F (MIL-C-23422F)

MIL-STD-171, Finishes (Metal and Wood)

This standard establishes and updates general finish codes and serves as a general guide to the selection of suitable materials, procedures, and system for cleaning, plating, painting and otherwise finishing of metal and wood surfaces. There are twelve finishing codes in this specification; below introduces chromium.

Finish No.

1.2 Chromium Coatings
1.2.1 Decorative plating, QQ-C-320, class 1

  • 2.1.1 Type I, bright
  • 2.1.2 Type II, satin

1.2.2 Engineering plating, QQ-C-320, class 2; thickness and undercoating, if necessary, as specified

The current revision of MIL-STD-171 is Rev. F (MIL-STD-171F)

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