Basics of Zinc Phosphate Treatment
Phosphorus exists in several forms, such as orthophosphoric acid, metaphosphoric acid, and pyrophosphoric acid, which are commonly used in the field of surface treatment involving metals. Particularly, phosphates like pyrophosphoric acid and tripolyphosphoric acid, which are derived from orthophosphoric acid, are indispensable for metal treatment.
Table of Contents
1. Introduction
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2. Classification of Phosphate Treatments / 2.1 Types of Phosphate Treatments
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2. English: “2. Classification of Phosphate Treatments / 2.2 Classification by Material / 2.3 Classification by Coating Characteristics
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2. Classification of Phosphate Treatments / 2.4 Classification by Application
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3. Mechanism of Coating Formation in Phosphate Treatments / 3.1 Properties of Phosphoric Acid”
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3. Mechanism of Coating Formation in Phosphate Treatments / 3.2 Coating Deposition Mechanism (Excluding Iron Phosphate Treatment)
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3. Mechanism of Coating Formation in Phosphate Treatments / 3.3 Coating Deposition Mechanism (Iron Phosphate Treatment)
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4. Management Methods for Phosphate Treatments
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5. In Conclusion
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1. Introduction
Phosphorus exists in several forms, such as orthophosphoric acid, metaphosphoric acid, and pyrophosphoric acid, which are commonly used in the field of surface treatment involving metals. Particularly, phosphates like pyrophosphoric acid and tripolyphosphoric acid, which are derived from orthophosphoric acid, are indispensable for metal treatment.
✓Metaphosphoric acid is used as a reducing agent that aids chemical reactions on metal surfaces during plating
✓Pyrophosphoric acid and other condensed phosphoric acids have the ability to stabilize metal ions and are used as water softening agents, and sometimes in the copper plating process
✓Although orthophosphoric acid does not cause reduction reactions, it is used as a component in degreasers due to its role in pH adjustment in alkaline environments and in dispersing oils. Additionally, orthophosphoric acid reacts with heavy metal ions to form insoluble salts. This property has been utilized in the development of phosphate treatment technologies that create protective layers on metal surfaces, which are widely used
2. Classification of Phosphate Treatments / 2.1 Types of Phosphate Treatments
2.1 Types of Phosphate Treatments
There are several different types of phosphate treatments. The four main types used industrially are as follows: