Zinc Phosphating
Process
Zinc phosphate is a porous crystalline coating produced on ferrous metal through the reaction of the phosphate solution with the surface of the metal. These coatings are widely used for prolonging the life of organic coatings, providing good paint bonding, improving corrosion resistance and providing an excellent base for holding lubricants.
Prior to phosphating the metal parts are cleaned in an electrically charged alkaline washing solution, a second still washing solution and immersed in a weak solution of hydrochloric acid to remove any residues of surface contaminants and prepare the work for the phosphate process. The cleanliness of the surfaces of the components to be phosphated is a key determinant in the quality of the finished product. An inhibitor is used in the hydrochloric solution to minimise the risk of hydrogen entering the surface of the metals.
Processing Equipment
We have both rack and barrel capabilities. Hydrogen de-embrittlement is carried out in a box furnace should it be required. All process information is held in our job information system to ensure product repeatability. All process information for each individual job is logged for traceability through both the phosphate line and hydrogen de-embrittlement oven.
Quality Assurance
Barrel loads are inspected for uniformity. Average coverage achieved is 6-12grams per cubic metre. AMTS is accredited to ISO9001:2000