Metal Pretreatment

Aluminum Processing

After the metal substrate has been thoroughly cleaned, many products will receive a chemical pretreatment prior to the application of the finish coating. When duration of service and quality of finish are highly important, premium metal finishes are built atop Crest Chemicals' metal pretreatment solutions.

Metal pretreatment chemicals are also known as conversion coatings. Conversion coatings are chemical solutions that can increase the surface area or change the surface chemistry of the substrate to promote adhesion and improve corrosion resistance with a chemical or electro-chemical process. They may also be used for lubricity, increased surface hardness, decorative color, and as a primer for paint. Conversion coatings may be thick or thin, or light or heavy, and the type of metal pretreatment is dependent on the substrate and the desired finish. Examples include chromate conversion coatings, phosphate conversion coatings, black oxide, and anodizing.

Ferrous metals commonly use iron or zinc phosphate conversion coatings prior to finish coating application, but may also use other metal pretreatments such as manganese phosphate, black oxide or zinc plate chromate as the finish. Non-ferrous metals like aluminum or magnesium commonly use a chromate conversion as a primer for finish coatings, but may also use anodizing as the finish.

Crest Chemicals carries a full line of high quality iron, zinc, and manganese phosphates as well as, chromate conversion solutions for magnesium, zinc, cadmium and aluminum. Crest also carries chemical solutions for black oxide and anodizing.