Aluminum Powder Coating Pretreatment
Aluminum chromate under heat cured powder paint is a proven and acceptable pretreatment however the chromate gel coating must be thin. Two main finishing technologies are used with aluminium.
Like the dip zirconium or other transitional metals are not as robust as some non chrome and chrome options but the performance can be good to very good if the powder layer is done right.
Aluminum powder coating pretreatment. Pretreatment is a process that your manufacturer goes through to remove all grease oils and dirt from the aluminum surface. Once the oxide layer is removed the surface has to be painted powder coated primed or chemically treated to prevent the regrowth of the oxide layer. Pre treatment methods of metal substrate prior to powder coating are divided into 2 type phosphating and chromating.
What is the powder coating process. Pretreating creates a surface that the coating can adhere to whether the coating is liquid or powder. The moisture left in a heavy coating will out gas sort of explode through the powder paint and leave corrosion opportunities.
The pretreatment process can involve either spray or immersion cleaning that must ensure metal is clean surface etched and that any defects do not show through the coating. Plus pretreatments heighten the performance value of a coating increasing its life and helping to prevent corrosion. Chemical clean de oxidation and zirconium pretreatment can also be effective in treating aluminum for outdoor use.
They need to do this before painting or powder coating to strengthen adhesion. The oxide layer can be removed chemically as well. This process has multiple steps and each one of them is important.
The powder coating process generally comprises three separate parts but each as important as the other. 1 pre treatment before the powder coating is applied on any substrate it is advisable to undergo pre treatment in order to enhance the durability of the powder coating. Pretreatment ensures that the metal is adequately prepared to ensure that the powder adheres correctly to clean and prepared metal and will give the durability that will be expected.
We will start with the first. Since first being developed in the 1960s companies powder coating onto aluminium have commonly used hexavalent chromate based pre treatment systems to ensure the coating adheres chemically to the substrate. That is the hows and whys of pretreatments but what about the whos and whens.
This can be a solid way to treat the aluminum if the powder layer is complete and thick enough and performance expectations are not too extreme such as in a coastline environment. Aluminum treated with a chemical treatment pretreatment remain paintable with good paint adhesion longer than abraded aluminum. Anodising and powder coating.
So doing a thorough job is what will ensure pretreatment success.