Background:

Electroless Nickel is an auto-catalytic process that deposits a layer of nickel alloyed with the reducing agent used, normally phosphorous.  The deposit thickness is very uniform and free of the edge buildup (“dog boning”) due to the fact that no current is used.

Guidelines:

Electroless nickel deposits can vary widely in characteristics.  Deposits are generally semi-bright, but this will vary depending on bath composition and surface finish of the base material.  Phosphorous content can range between 0 to over 12 percent.  Deposit hardness decreases as the phosphorous content increases.  Hardness may be maximized by post baking.  Baking can also increase adhesion of the deposit, especially on zincated aluminum base materials.  Solderability is best at lower phosphorous contents and will tend to degrade with time.  High phosphorous alloys are non-magnetic.

Common Specifications:

MIL-C-26074

Class – Post bake

Class 1 – As plated, no subsequent heat treatment (Hydrogen embrittlement relief is not considered a heat treatment)

Class 2 – Heat treated to obtain required hardness: May be used on all metals not affected by heating to 500°F and above

Class 3 – Aluminum alloys nonheat-treatable, and beryllium alloys processed to improve adhesion of the nickel deposit

Class 4 -  Aluminum alloys, heat-treatable, processed to improve adhesion of the nickel deposit

Grade  -  Minimum thickness

Grade A – 0.0010 inch minimum thickness

Grade B -  0.0005 inch minimum thickness

Grade C -  0.0015 inch minimum thickness

ASTM-B733

Phosphorous content:

Type I  -  No requirement

Type II -  1% to 3 % Phosphorous

Type III -  2% to 4% Phosphorous

Type IV -  5% to 9% Phosphorous

Type V  -  10% and over Phosphorous

Service Conditions – minimum thickness

SC-0     0.000004 inch minimum

SC-1     0.0002 inch minimum

SC-2     0.0005 inch minimum

SC-3     0.001 inch minimum

SC-4     0.003 inch minimum

Post Treatment

Class 1  -  No post bake

Class 2  -  Post bake 260°C to 400°C to produce 850 HK100 minimum

Class 3  -  Post bake 180°C to 200°C for 2 to 4 hours

Class 4  -  Post bake 120°C to 130°C for 1 hour minimum

Class 5  -  Post bake 140°C to 150°C for 1 hour minimum

Class 6  -  Post bake 300°C to 320°C for 1 hour minimum

Additional Specifications

AMS 2404

AMS 2405

Note:

Government and/or industry specification(s) should be called out when required by the blue print or per customer requirement. If a specification callout is used as a type of shorthand, then qualify the callout to say that only hardness/thickness certification (as appropriate) is required. A government/industry specification callout invokes additional testing that may not be required and will increase the cost of plating.

[Home] [Up] 

Send mail to pmpmail@pmplating.com   with questions or comments about this web site.