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Motor Frame Design
Published in Wei Tong, Mechanical Design and Manufacturing of Electric Motors, 2022
The primary types of phosphate coatings include manganese, iron, and zinc coating. Among them, manganese phosphate coating has the highest hardness and superior corrosion and wear resistance. Therefore, manganese phosphate coating is extensively used to improve friction properties of sliding components such as engine pistons, gears, camshafts, and power transmission systems. Iron phosphate coating inhibits corrosion and improves the adhesion and durability of paint finishes. Due to the low cost and moderate corrosion resistance, this type of phosphate coating is basically suitable for indoor equipment. Zinc phosphate coating can provide the highest corrosion resistance. Hence, it is widely used in the automotive industry and in certain sectors of the appliance and electronics industries.
Introduction to Corrosion
Published in S.K. Dhawan, Hema Bhandari, Gazala Ruhi, Brij Mohan Singh Bisht, Pradeep Sambyal, Corrosion Preventive Materials and Corrosion Testing, 2020
S.K. Dhawan, Hema Bhandari, Gazala Ruhi, Brij Mohan Singh Bisht, Pradeep Sambyal
In this process, metal is immersed in an ortho-phosphoric acid bath containing other metal salts such as zinc phosphate and manganese phosphate, giving a layer of phosphate on the steel surface. During the steel forming process, phosphating is often carried out in order to improve the surface properties of the sheet. The main components of a phosphating solution are: Ortho-phosphoric acid (H3PO4);Bivalent metal cations: Zn2+, Mn2+, Fe2+;Accelerator—an oxidizing reagent (H2O2, KNO3, etc.) increasing the coating process rate and reducing the grain size of the deposit.
The role of surfactants in phosphate conversion coatings
Published in David R. Karsa, Surfactants in Polymers, Coatings, Inks and Adhesives, 2020
Phosphating is a widely used method of reducing wear on machine elements and moving parts [14]. Phosphate coatings function as lubricants and, in addition, their ability to retain oils and soaps further enhances this action. Heavy manganese phosphate coatings, supplemented with proper lubricants, are most commonly used for wear resistance applications [15]. The power used in deep drawing operations leads to a great amount of friction between the steel surface and the die, which decreases the speed of drawing operations and the service life of tools and dies [16,17]. Application of light to medium weight non-metallic zinc phosphate coatings to steel surfaces, which permit the distribution and retention of a uniform film of lubricant over the entire surface, prevents metal to metal contact and makes possible the cold forming and extrusion of more difficult shapes than is possible without the coating [18]. A combination of zinc phosphate and lubricant film prevents welding and scratching of steel in drawing operations and greatly decreases rejections. Further, phosphate has also been found to be useful in absorbent coatings for laser surface hardening [19] and thermal control coatings in satellite components [20].
Dry sliding wear behaviour of steel (AISI 1078) after coating with steam treatment and manganese phosphating
Published in Tribology - Materials, Surfaces & Interfaces, 2021
Siddhant Kaushik, Ranvir Singh Panwar
The phosphating process could be applied to different substrates of metal, such as steel, cast iron or zinc. Different types of coatings of modified phosphate [2–5], zinc phosphate [9–12], iron phosphate [13] and manganese phosphate [14–16], are used. High hardness and good corrosion and wear resistance by the manganese phosphate coatings make it a superior choice for tribological applications among the above-mentioned coatings of phosphate [1,17]. Apart from this, the oil-retaining ability of manganese phosphate coatings eases low-friction motion which also supports better wear resistance [16,18]. Manganese phosphate coatings are developed by dipping iron (or) steel into a solution of phosphoric acid and manganese carbonate [17].