1.2 - Quality Control & Analysis 

QC/QA on Parts for Export
With the advent of the common market in Europe, many enthusiastic foreign manufacturers with government support have begun to encourage a new quality standard called ISO-9000. In reality, this is a comprehensive guideline which ties together many random specifications that previously existed pertaining to administration, personnel training, purchasing, production, and OC/QA.

Parts for Certification
In America, we still have military specifications as the dominant source of processing standards, (ie. MIL-A-8625 Anodic coatings for aluminum and aluminum alloys). Such standards are supplemented and used in conjunction with many major engineering specifications such as ASM-2472 and ASTM-B-580. Respectively, these standards are produced by the Society of Automotive Engineers and the American Society of Testing and Materials. Most decorative architectural anodizing is done to standards as described by the AAC (Aluminum Anodizer Council).

Artful Planning for Anodizing
Despite the advent of computers and the information explosion, the anodizing process is still a coordination of many variables. By way of comparison, anodizing is more like baking a cake matched to the precise numerically controlled machining of manufactured parts. In most cases, an anodizer has only one chance to process aluminum parts correctly (i.e. the cake either rises or it doesn’t). Hence, there are many controlled ingredients for the successful anodizing of machined parts:

Alloy- The designation of aluminum alloy, purity, and prior heat treatment (i.e 6061-T6) is important. The more pure the alloy... the more functional the anodic coating.

Fixturing- Mounting the aluminum part tightly so the uninterrupted electrical current will pass through it.

Solution- Concentration of sulfuric acid or any other electrolyte used to promote formation of an oxide when electricity is applied.

Current- Direct amperage for a rectifier within a specified voltage to grow aluminum oxide for aluminum, neither too fast, nor too slow.

Time, Thickness, Temperature, & PH- The thickness of the coating is proportional to the time of processing, but there is an upper limit for each alloy. The hardness of the coating varies with the reduced temperature of the electrolyte, whereas the corrosion resistance is dependent on the time, temperature, and pH of the sealing process. Inspection- Examining the parts before, during, and after processing is crucial. Test coupons are used for the certification of coating thickness, continuity, adhesion, hardness, salt spray, UV light resistance, etc.

Measurement- Achieved using calibrated instruments, gages, micrometers, and calipers traceable to the NBS -National Bureau of Standards.

Personnel- Conscientious, experienced people -trained and dedicated to the task of quality control and quality analysis...the key component for anodizing to any measurable standard.

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