Iron phosphate is the oldest surface treatment method ever known and applied. It is used in preparing the product groups called indoor products such as lighting fixtures, chairs and etc. for paint. Its resistance against corrosion is low and it is applied easily. The institution investment and treatment cost are low as well. On iron phosphate and iron-steel surfaces, it leads to a layer on which mostly blue turning yellow-carmine.
Iron phosphate coating can be applied in three different ways: Wipe Iron Phosphate, Immersion Iron Phosphate and Spray Iron Phosphate.
Wipe Iron Phosphate; This product is applied by individuals using a sponge, fabric or brush and at the same time, it makes degreasing and phosphating. It is suggested to be prepared 1/10 solution in wipe phosphate treatments. After treatment, phosphated pieces have to be dried to clear of the chemical stains. Especially in winter, we suggest the prepared treatment solution with high temperature. It is the cheapest and easiest method of all. It requires extra attention because it is applied by individuals.
Immersion Iron Phosphate; The treatment parameters (such as temperature, concentration, waiting time, ph and etc.) are important to be used in proper way. The first stage is alkaline degreasing bath and second stage is to use a degreased material. It is recommended to use two seperate rinsing bath. The ph of the alkaline degreasing baths is 14. At the third stage, the iron phosphate bath whose treatment ph is 4-5 has damaging effects. A surface which has not been rinsed well increases the ph of the iron phosphate and damages it after some time. This has also negative effects on the chemical use. After iron phosphating, the surface is rinsed again. The next treatment is passivation bath. At the last stage, the materials treated 30 seconds or 1 minute are dried at maximum 120 ºC in drying units. We recommend the passivation bath to be at least 50 ºC. The metal pieces are also recommended to be painted on the very same day after phosphatizing.
Spray Iron Phosphate; The treatment parameters (such as temperature, concentration, waiting time, ph and etc.) are important to be used in proper way. First investment cost is higher than immersion iron phosphating. It is so advantageous in terms of chemical use, energy and effort. It is applied as two processes.
1. type; two times rinsing after alkaline degreasing and then spray phosphating. Rinsing again, passivation and drying.
2.type; first bath spraying, degreasing additive in iron phosphate bath and then rinsing, passivation and ends with drying.
Drying should be at maximum 120 ºC.