| Process | Metal | Applicable Specification | Normal Coating Thickness and Color or Appearance | Remarks |
|---|---|---|---|---|
| ANODIZE – CHROMIC ACID | ALUMINUM | MIL-A-8625 TYPE I –Conventional TYPE IB- Low Voltage CLASS 1- Non Dyed | 00002-.0001 max. Clear to dark gray depending on alloy. | Not to be applied to alloys with copper content in excess of 5.0% or silicon in excess of 7.0% and when total alloying elements exceed 7.5%. Non-conductive, good paint base, poor abrasion resistance, not good for dyes except black. Should be used for close tolerance parts. |
| ANODIZE – BORIC SULFURIC ANODIZE | ALUMINUM | BAC 5632 CLASS 1 AND CLASS 5 | N/A | Boric Sulfuric Anodize is commonly used an as alternative to Chromic Anodize because the chemicals used during the process are more environmentally friendly than those in chromic acid anodize. |
| ANODIZE - SULFURIC ACID | ALUMINUM | MIL-A-8625 TYPE II CLASS 1-Non Dyed CLASS 2-Dyed AMS 2471 | .00007-.001 Clear All colors | Not to be applied to assemblies or parts with joints or recesses which might entrap solution. Good electrical barrier and paint base. May be dyed in all colors. Dichromate seal, when specified, will impart yellow color. Produces excellent decorative finishes when the part is either polished, brushed, or bright dipped prior to anodizing. Good corrosion and abrasion resistance. |
| Hard Anodize | ALUMINUM | MIL A-8625 Type lll CLASS 1- Non Dyed CLASS 2 - Dyed AMS 2469 | Unless otherwise specified, .0016/.0024 will be applied. Color will vary with alloy and thickness | Dense hard ware resistant coating. Coatings are approximately 50% penetration and 50% build up. Excellent dielectric and heat absorption properties. May be considered for minor salvage applications. Sealing greatly increases corrosion resistance, but slightly reduces wearing qualities. |
| BLASTING (includes glass bead and powder blasting) | ALL | MIL-STD-1504 Or as required by applicable process specification | May remove 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 | NONE | Removes metal Bright | Chemical polishing which improves appearance of finishes on aluminum, brass and copper. Used for cleaning metal before welding and pressure testing. |
| CADMIUM | ALL | AMS-QQ-P-416 TYPE I-Without supplementary chromate treatment. TYPE II-With supplementary chromate treatment. AMS 2400 | CLASS 1- .0005 Min. CLASS 2- .0003 Min. CLASS 3- .0002 Min. TYPE I- Clear. TYPE II-Gold, Olive Drab, Black Treatment | Most commonly used plating. High density of plate affords excellent corrosion resistance. TYPE 1 coating is very susceptible to stains and fingerprints. TYPE II coating is excellent for resistance to moisture and humidity, and as a paint base. Chromate colors besides gold are clear, olive drab and a black treatment. TYPE III is a good paint base. Stress relief is required on metal with a hardness of Rockwell C34 or above and hydrogen embrittlement relief is required after plating on metal with a hardness of Rockwell C36 or above. |
| CHEMICAL FILMS | 4' x 3' x 3' 8' x 3' x 3' ft.'s | ALUMINUM | Gold or clear as specified. | Used mainly as a paint 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 than CLASS 1A coating. |
| (Alodine T5900) | TYPE II-ROHS Compliant | MIL-DTL-5541/+MIL-C-5541 TYPE I-CLASS 1A for maximum protection against corrosion on painted or unpainted surfaces. TYPE I-CLASS 3 for protection against corrosion where low electrical resistance is required. No dimensional change. |
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| ELECTROLESS NICKEL | ALL | AMS-C-26074 CLASS 1- As plated, no subsequent heat treatment. CLASS 2- Heat treated to obtain the required hardness. CLASS 3- On aluminum alloys, non-heattreatable, & beryllium alloys, processed to verify nickel adhesion. CLASS 4- On aluminum alloys, heat-treatable, processed to verify nickel adhesion. AMS 2404=Thks. As specified. | Semi-bright GRADE A= .0010 min. GRADE B= .0005 min. GRADE C= .0015 min. | 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. CLASS1 and CLASS2 coated steel parts, Rockwell C40 or above, are baked for hydrogen embrittlement relief. CLASS 2 coated parts are additionally heated to 500 degrees F. or more, to harden the nickel deposit to 800 Knoop or better. CLASS 3 and 4 coated parts shall be baked for 1-1 ½ hours at 375 degrees F. respectively. |
| ETCHING | MOST | NONE | Removes metal. Dull to bright. | To improve appearance, remove burrs and oxidation, clean for spot welding, give stain finish, prepenetrant etch, etc |
| TITANIUM PRE AND POST CLEANING | TITANIUM CRES | ACES 1178 | Cleaning and surface preperation of CRES materials previous and after brazing/welding | |
| PAINTING (Spray) | ALL | MIL-PRF-85335 MIL-PRF-22750 MIL-PRF-23377 MIL-PRF-85582 | Thickness as specified. Colors per FED-STD-595 or custom matched. | Our facilities can apply materials such as alkyd, acrylic, epoxy, and polyurethane enamels, vinyl and acrylic lacquers, varnishes and resin coating, epoxy, acid-wash, red-oxide, and zinc chromate primers. Finishes such as class A, hammertone, wrinkle, and texture. Also, see SOLID FILM LUBRICANT. |
| PAINTING (Electrostatic) Powder coating | ALL | Contact us with specific requirement | Thickness as specified and colors per FED-STD-595 or custom matched | Powder coating is a high quality, durable, dry finishing process. Its used is mstly decorative but it also provides a protective coating to the surfaces on which it is applied. |
| PASSIVATE | STAINLESS STEELS | AMS 2700 Method 1/+AMS –QQ-P-35 TYPE II- Medium temp. nitric acid solution with sodium dichromate additive. TYPE VI- Low temp. nitric acid solution. TYPE VII- Medium temp. high concentration nitric acid ASTM A 967. | No dimensional change. No appearance change. | Dissolves all traces of foreign materials such as pieces 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 present of rust and/or heavy heat treat scale may necessitate a prepickle. Our inspection personnel conduct the required copper sulfate, salt spray, and water immersion inspection test in our own testing department and chemical laboratory in accordance with AMS-STD-753 and ASTM B 117. (See TESTING). |
| PENETRANT INSPECTION | ALL | ASTM E 1417 TYPE I – Fluorescent dye TYPE II – Visible dye METHOD A – Water-washable METHOD B – Post emulsifiable (lipophilic) METHOD C – Solvent removable METHOD D – Post emulsifiable (hydrophilic) | Prepenetrant etch of .0002 – .0004 metal removal on all alloys when approved by consumer | This process is generally used on aluminum, magnesium, and stainless steels. It can, however, be useful on other metals and materials. Detects cracks, discontinuities, corrosion, welding flaws, laps, cold shuts and porosity. Prepenetrant etching is performed in house when required and approved. Critical surface finishes and areas with close tolerances are masked, as required, to protect them from metal removal, prior to the etching operation. |
| SOLID FILM LUBRICANT | ALL | AS5272 MIL-PRF-46010 | .0003-.0005 Dull gray to black. | Pretreatment compatible with the base material is normally necessary (ie; anodize, chemical film, blasting and phosphate etc.) Low co-efficient of friction reduces wear, prevents galling and seizing. Excellent fluid and corrosion resistance when used in conjunction with pretreatment. |
| TESTING (for lot acceptance) | ALL PLATED AND UNPLATED | METHOD 101- Water immersion. METHOD 102- Copper sulfate. | No dimensional change. | These tests are designed to verify the integrity of various metals and metal surface finishes. Water immersion and copper sulfate methods are used to check on the passivity of stainless steel after the passivation process. |
| TIN | ASTM B 545 CLASS A – Mild service with no exposure to atmosphere CLASS B – Mild service for sol- dering or antigalling CLASS C – Moderate service with indoor exposure CLASS D – Severe service with exposure to dampness and/or mild corrosion conditions CLASS E – Very severe service | CLASS A- .0001 min. CLASS B- .0002 min. CLASS C- .00032 min. .0004 for steel substrates CLASS D- .0006 min. .0008 for steel substrates CLASS E- .0012 min. Dull gray to bright appearance | Dull ( matte) or bright appearance must be specified. Underplate of copper (.0001 min.) or nickel (.000050 min.) must be used on brass and zinc alloys to prevent zinc migration. For CLASS A plating that will not be exposed to solder temperatures (especially those that must function as electrically conductive surfaces), a nickel underplate of .000050 min., shall be applied prior to tin plating. Dull and bright tin have excellent solderability and fair corrosion resistance. At room temperature dull (matte) plating oxidizes slowly but bright plating oxidizes less readily. Dull and bright tin have low electrical resistance and antigalling properties. | |
| Zinc Plating | ASTM B633 TYPE I without supplementary treatment TYPE II with colored chromate TYPE II with colorless chromate | Fe/2n 25 sc 4 .00" Fe/2n 12 sc 3 .0005" Fe/2n 8 sc 2 .0003" Fe/2n 5 sc 1 .0002" | Gives galvanic protection to base metal. Untreated (TYPE l) zinc plating does not maintain its bright surface for a very long period of time. TYPE ll and TYPE lll 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: SC4-Very Severe: Exposure to harsh conditions, are subject to frequent exposure to moisture, cleaners and saline solutions, and damage by denting, scratching, or abrasive wear. SC3-Severe: Exposure to condensation, perspiration, infrequent wetting by rain, and cleaners. SC2-Moderate: Exposure mostly to dry indoor atmospheres but subject to occasional condensation, wear, or abrasion. SC1-Mild: Exposure to indoor atmospheres with rare condensation and subject to minimum ware or abrasion. |
