Copper Passivation Treatment of Brass Nut by Salt Spray for 48 Hours

19-03-20

The industrial upgrading is accelerating, and the requirements for various industrial products are increasing. Among them, the quality requirements for all kinds of copper products are getting higher and higher. The requirements for corrosion resistance (salt spray test) of copper parts are getting higher and higher. The performance requirements for 48 hours, 72 hours, 96 hours or 168 hours of salt spray test are often met, such as non-oxidation, non-removal of copper green, and so on. It is well known that copper parts are easily oxidized and discolored to oxidized black, and the salt spray corrosion resistance of untreated copper parts is generally no more than 1 hour.

The requirement of 48 hours for brass nuts is still very challenging. A large number of experiments have proved that a copper passivation treatment process can meet the test requirements. Here is the operation method of this process.

Tools/raw materials

Copper cleaning agent MS0217

Copper Passivation Liquid MS0423

Copper Polishing Solution MS0308-1

Brief Introduction of Process Flow

One

Pretreatment Overwater Passivation Overwater Pure Water

1. Pretreatment: including oil removal and cleaning, oxide removal, polishing and other processes to prepare for passivation.

2. Washing is to wash the pretreatment liquid remaining on the surface of the workpiece to prevent contamination of the next process and to flow tap water.

3. Passivation. Place the cleaned workpiece in the passivation solution and soak it at room temperature for more than 5 minutes.

4. Overwater is to flush the passivation liquid remaining on the surface of the workpiece and flow the tap water.

5. Super-pure water is to prevent water marks (or it can be cleaned with hot water at 60-80 degrees Celsius).

Note: Each process step can be adjusted appropriately according to the actual production situation.

END

Operational procedures and methods

One

Pretreatment:

(1) Degreasing and oxidizing skin cleaning, cleaning the dirty surface of brass nuts and oxides with copper cleaning agent, generally about 3 minutes;

(2) Rinse the brass nuts with clean water, and clean the remaining copper cleaning agent on the surface of the brass nuts.

Tools/raw materials

Copper cleaning agent MS0217

Copper Passivation Liquid MS0423

Copper Polishing Solution MS0308-1

Process introduction

One

Pretreatment Overwater Passivation Overwater Pure Water

1. Pretreatment: including oil removal and cleaning, oxide removal, polishing and other processes to prepare for passivation.

2. Washing is to wash the pretreatment liquid remaining on the surface of the workpiece to prevent contamination of the next process and to flow tap water.

3. Passivation. Place the cleaned workpiece in the passivation solution and soak it at room temperature for more than 5 minutes.

4. Overwater is to flush the passivation liquid remaining on the surface of the workpiece and flow the tap water.

5. Super-pure water is to prevent water marks (or it can be cleaned with hot water at 60-80 degrees Celsius).

Note: Each process step can be adjusted appropriately according to the actual production situation.

END

Operational procedures and methods

One

Pretreatment:

(1) Degreasing and oxidizing skin cleaning, cleaning the dirty surface of brass nuts and oxides with copper cleaning agent, generally about 3 minutes;

(2) Rinse the brass nuts with clean water, and clean the remaining copper cleaning agent on the surface of the brass nuts.

Brass passivation treatment:

(1) Place cleaned brass nuts in passivation solution and soak them in passivation solution. Pay attention to the full contact between the powder and the workpiece, so that a complete passivation film can be formed on the surface of the copper parts. The passivation time is more than 15 minutes (due to the long salt spray time, the passivation time will be extended properly), and the passivation temperature is over 20 C.

(2) Rinse with clean water to clean the residual passivation solution on the surface of copper mesh;

Cleaning and drying of super pure water:

Cleaning with pure water is to prevent watermarking on the surface of copper parts, if using hot pure water, the effect is better.

The drying temperature should not exceed 100 (?) C, generally about 80 (?) C is the best.

Matters needing attention

Passivation for at least 5 minutes, salt spray performance requirements can be further extended appropriately

The medicine can't be contaminated.

Introduction of Knurled brass nut's Function and Performance