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Plating and other services to Military, ASTM, and most Industry Specifications
ANODIZE
SULFURIC ACID ALUMINUM
MIL-A-8625 TYPE II
CLASS 1 - Non Dyed
CLASS 2 - Dyed
0.00007-0.001
Clear
All Colors
Not to be applied to assemblies or part with joints or recesses which might entrap solution. Good electrical barrier and paint base. May be dyed in all colors. Dichromate seal will impart yellow color. Produces excellent decorative finishes when the part is either polished, brushed, or bright dipped prior to anodizing. Good abrasion resistance.
BAKING
Embrittlement relief is required after cleaning, pickling or plating on all metals with hardnesses above Rockwell C40. ALL In accordance with applicable plating specification No dimensional change Slight staining may result Used for hydrogen embrittlement or stress relief before and/or after processing, for improving the adhesion of plating the base metal, and increasing the hardness of plating.
BLASTING
(includes glass bead and powder blasting)
ALL MIL-STD-1504 Removes metal
Dull to semi-bright For removing scale and rust, etc., and blending imperfections. The amount of metal removed will depend on media selected. May be used for decorative and optical finishes. Provides uniform matte finish before decorative processing.
BRIGHT DIPS
ALUMINUM, BRASS, COPPER Removes metal
Bright Chemical polishing which improves appearance of finishes on aluminum, brass and copper. Used for cleaning metal before welding and pressure testing
CHEMICAL FILMS
(Alodine, Iridite, etc.) ALUMINUM MIL-C-5541, MIL-DTL-5541f
TYPE I Compositions containing Hexavalent Chromium
TYPE II Compositions containing no Hexavalent Chromium
CLASS 1A for maximum protection against corrosion on painted or unpainted surfaces
CLASS 3 for protection against corrosion where low electrical resistance is required. No dimensional change
Gold or clear as specified. Used mainly as a point base that improves paint adhesion. Good corrosion resistance. Electrically conductive. Normally gold color unless otherwise specified. CLASS 3 coating is used primarily for low electrical resistance contact and has less corrosion resistance that CLASS 1A coating.
CHROMIUM
QQ-C-320
CLASS 1 - Corrosion protective (decorative)
TYPE I - Bright
TYPE II - Satin
CLASS 2 - Engineering (hard) CLASS 1 - 0.0001 - 0.00005 (plus underplate)
CLASS 2 - 0.002 unless otherwise specified
Dull to bright Decorative chrome is normally applied over nickel plate. TYPE I bright coating is put on either the base metal that is polished or as is. TYPE II satin coating is put on the base metal that is either blasted, grained or brushed. Hard chrome is plated directly on the base metal. Parts requiring heavy metal deposits should be overplated and ground to the final finished dimension.
DRY FILM LUBRCATION
or DRY LUBE
See SOLID FILM LUBRICANT
ELECTROLESS NICKEL
AMS 2404
CLASS 1 - As plated, no subsequent heat treatment
CLASS 2 - Heat treated to obtain required hardness
CLASS 3 - On aluminum alloys, nonheat-treatable, & beryllium alloys, processed to verify nickel adhesion
CLASS 4 - On aluminum alloys, heat-treatable, processed to verify nickel adhesion
THICKNESS AS SPECIFIED
Semi-bright 100% uniformity of plating thickness on all accessible internal and external areas. Exceptionally good for salvage purposes. Good corrosion, oxidation, and wear resistance. Facilitates soldering on aluminum and brazing on stainless steel. CLASS 1 and CLASS2 coated steel parts. Rockwell C33 or above, are baked for hydrogen embrittlement relife. CLASS 2 coated parts are additionally heated to 450 degrees F. or more, to harden the nickel deposit. This heat treatment should increase the plating hardness to 800 Knoop or better, for CLASS 2 coatings.
ETCHING Removes metal.
Dull to bright To improve appearance, remove burrs and oxidation, clean for spot welding, give satin finish, etc.
HYDROGEN EMBRITTLEMENT RELIEF
See BAKING
IRIDITE
See CHEMICAL FILMS
NICKEL (Electrodeposited)
QQ-N-290
CLASS 1 - Corrosion protective
CLASS 2 - Engineering (Also see SULFAMATE NICKEL) CLASS 1
GRADE A - .0016
GRADE B - .0012
GRADE C - .0010
GRADE D - .0008
GRADE E - .0006
GRADE F - .0004
GRADE G - .0002
CLASS 2 - as specified There is a nickel finish for almost any need. Nickel can be deposited in soft or hard form, dull or bright finish. Corrosion resistance is related to the thinkness applied. Low thermal expansion. Slightly magnetic. CLASS 2 plating will be .002 to .003 thick unless otherwise specified, but may be controlled to fit any engineering application. Embrittlement relief is required on all metals with hardnesses above Rockwell C40.
PASSIVATE
STAINLESS STEELS
QQ-P-35
TYPE II - Medium temperature nitric acid solution with sodium dichromate additive
TYPE VI - Low temp. nitric acid solution
TYPE VII - Medium Temp. nitric acid solution
TYPE VIII - Medium temp. high concentration nitric acid solution No dimensional change
No appearance change Dissolves all traces of foreign metals such as peices of iron particles, tool scrapings, chips, etc., that will cause rust or stain spots if they are not removed. A thin, transparent passive film forms over the surface and prevents this condition from occurring. The presence of rust and/or heavy heat treat scale may necessitate a pre-pickle. For the 400 and precipitation hardening series of stainless steels, the proper heat treatment is very important to ensure complete passivation. Our inspection personnel conduct the required copper sulfate, potassium fericyanide - nitric acid and water immersion inspection tests in our own testing department and chemical laboratory in accordance with MIL-STD-753 and ASTM B117. (see TESTING
PHOSPHATE
(Heavy) IRON AND STEEL DOD-P-16232 TYPE Z- Zinc base
CLASS 1 - Specified treatment of supplementary preservative
CLASS 2 - MIL-C-16173
GRADE 1 preservative treatment
CLASS 3 - No supplementary preservative treatment
CLASS 4 - Chemically converted .0002-.0006
1022 mg/sq ft minimum coating weight
Gray Used for corrosion protections of ferrous metals. Also used to prevent galling in cold extrusion and deep-drawing applications. Not recommended if the coating is expected to come in contact with alkaline materials or to be exposed to temperatures above 200 degrees F. CLASS 2 and CLASS 4 coatings extend the corrosion protection of the phosphate. MIL-L-3150 oil may be used as an alternative for very small parts under CLASS 2. CLASS 4 provides an improved break-in coating.
PHOSPHATE
(Light)
IRON AND STEEL TT-C-490 Zinc base,
TYPE I Minor dimensional change
150-500 mg/sq ft coating weight
TYPE V
500-1100 mg/sq ft coating weight. Gray Used for pretreatment of base metal for organic coatings such as primer enamel, lacquer, etc. Improves corrosion resistance of the base metal, and promotes better adhesion between the base metal and the organic coating. Also, use for post treatment of both cadmium and zinc plating.
PICKLING
In accordance with applicable plating specifications Removes metal
Cleaner and brighter surface Generally used as a cleaner to remove corrosion, rust, and scale from heat treating or weling. The hazards involved in this process should be investigated before using.
POLISHING
(limited capability)
Removes metal
Satin to bright Bright buffing and satin brushing, or graining for plated or unplated decorative finishes. Removes surface imperfections.
PREVENTIVE COMPOUND SOLVENT CUTBACK COLD- APPLICATION
MIL-C-16173
GRADE 1 - Hard film
GRADE 3 - Soft film
GRADE 4 - Transparent, non- tacky film
GRADE 5 - Hot water-low pressure removable film GRADE 1 - .004 max. (0 to 175 degrees F. resistant)
GRADE 2 - .002 max. (-40 degrees F. resistant)
GRADE 3 - .001 maximum
GRADE 4 - .002 max. (-40 to 175 degrees F. resistant)
GRADE 5- .001 maximum
Brown to black Corrosion preventives are applied in a petroleum solvent. The solvent evaporates leaving a protective film. GRADE 1 is for metals exposed to outdoor weather, for up to one year. GRADE 2 is for machine parts, indoors for up to six months. GRADE 3 is for displacing water and protection of interior parts for up to four months. GRADE 4 is for indoor or shed storage of parts. Also, where a tack-free or translucent coating is required. GRADE 5 is the same as GRADE 3 except the film is removed with hot water or low pressure steam.
SALT SPRAY TEST See TESTING
SOLID FILM LUBRICANT
MIL-L-46010 TYPE I & TYPE II
MIL-L-23398
MIL-L-45983
MIL-L-81329
MIL-L-85614 .0002-.0005
Dull gray to black Pretreatment compatible with base material is normally necessary (anodize, chemical film, cadmium plate, blasting if required, etc.).
Low co-efficient of friction reduces wear, prevents galling and seizing. Excellent fluid and corrosion resistance when used in conjunction with pretreatment
STRESS RELIEF See BAKING
SULFAMATE NICKEL QQ-N-290
CLASS 2 .002-.003 or as specified
Semi-bright Low stressed nickel deposit. Used for wear and abrasion resistance. Also, for heavy buildups on worn parts and for salvage purposes.
TESTING
PLATED AND UNPLATED
ASTM B117 - Salt spray
MIL-STD-753
METHOD 100 - Humidity
METHOD 101 - Water immersion
METHOD 102 - Copper sulfate No dimensional change
No appearance change These tests are designed to verify the integrity of various metals and metal surface finishes. The salt spray method is used extensively for testing of anodize, chemical films, and plated metal coatings. The salt spray, humidity, water immersion, and copper sulfate methods are used to check on the passivity of stainless steel after the passivation process.
ZINC
MINIMUM SALT SPRAY HOURS
ASTM B633
TYPE I - As Plated. Without supplementary treatment
TYPE II - With colored chromate conversion coatings 96 HRS
TYPE III - With colorless chromate conversion coatings 12 HRS
TYPE IV - With phosphate conversion
TYPE V - With colorless passivate 72HRS
TYPE VI - With colored passivate 120HRS
coatings
Fe/Zn 25 (25 microns)-.001
SC 4 (very severe)
Fe/Zn 13 (13 microns)-.0005
SC 3 (severe)
Fe/Zn 8 (8 microns)-.0003
SC 2 (moderate)
Fe/Zn 5 (5 microns)-.0002
SC 1 (mild)
TYPE I - Clear
TYPE II - Gold
TYPE III - Clear
TYPE IV - Gray
Dull to bright Gives galvanic protection to base metal. Untreated (TYPE I) zinc plating does not maintain its bright surface for a very long period of time. TYPE II and III treatments retard the formation of white corrosion products on the plated surface. The service life of zinc plating is a function of conditions such as thickness, exposure, and usage. The Service Conditions are as follows: SC 4 - Very Severe: Exposure to harsh conditions, or subject to frequent exposure to moisture, cleaners, and saline solutions, and damage by denting, scratching, or abrasive wear. SC 3 - Severe: Exposure to condensation, perspiration, infrequent wetting by rain, and cleaners. SC 2 - Moderate: Exposure mostly to dry indoor atmospheres but subject to occasional condensation, wear, or abrasion. SC 1 - Mild: Exposure to indoor atmospheres with rare condensation and subject to minimum wear or abrasion.
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