الوصف

Zn-638
Brightener for Acidic Potassium Chloride Zinc Plating
TECHNICAL DATA
Brightener for Zn-638 Acidic Potassium Zinc Plating
1. Properties
1. This product is made up of brightener and base solution. It is a fast
brightener with good plating.
2. The bath has excellent anti iron impurities. It is suitable for both rack plating
and barrel plating.
3. The plating is easy to passivator with multicolor, white-blue, and white color
because of its good gloss.
4. It is stable, with little consumption of brightener, wide range of temperature,
high cloud point. It is suit for high temperature production.
2. Bath composition and Operation condition
Bath
composition
and Operation
condition:
Rack plating Barrel plating
KCl 180~220g/L 200~240g/L
ZnCl2 60~70g/L 40~55g/L
H3BO3 30~35g/L 30~35g/L
ZN-638 A
brightener 0.3~1ml/L 0.2-1 ml/L
ZN-638 B 15-25ml/L 15-25 ml/L
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base solution
PH 4.5~5.5 5.0~6.0
Cathnode
current
density(Dk)
0.5~5A/dm2 0.2~3A/dm2
SK:SA 1:1.5~2 1:1.5~2
Anode 0＃zinc ingot 0＃zinc ingot
3. Bath Make-up
1. Add 2/3 volume of the tank with water, then add measured KCl and ZnCl2,
stirring until dissolved.
2. Slowly added with boric acid which is completely dissolved with water at 80
centigrade degree.
3. Then adding 1 ~ 2g / L zinc powder, stirred for 20 to 30 minutes, then filtered
into the clarification tank, add water to the calculated volume.
4. After diluting measured ZN-638 once with water, add into stirring bath,
stirring evenly before trial plating.
4. Bath Management
1. ZN-638A consumption is 100-150ml/KAH, ZN-638B consumption is
80-150ml/KAH.
2. Add with ZN-638A : Zn-638B = 1-2:1(v%), then mix completely. Diluting 1-2
times with water. The less and more frequent, the better.
3. If original bath is for potassium chloride zinc plating, add directly without
special treatment.
4. Lower PH value with 5-10 times diluted HCl.
5. It is better to dissolved completely before adding to ensure the normal
production.
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5. Troubleshooting
Phenomenon Cause Action
Bath is cloudy, brightener
consumed in large
1. excessive iron impurities
2. too more the solid
3. pH value is too high or
Low
4. the temperature is too
high
5. KCl content is too high
6. bad pretreatment
1. add WZn acid zinc
impurity agents or large
processing
2. filter
3. adjust to the range
4. cooling
5. adjust to the range
6. to strengthen
pretreatment
Bad throwing
1. brightener inadequate
2. the potassium content is
low, high chloride
3. pH value is too low or
too high
4. the temperature is too
high
5. the current density is too
small
1. add brightener properly
2. adjusting after analysis
3. adjust to the range
4. drop to the range
5. to improve the current
density
Easy burnt, with drum
printing, bright range is
small
1. too more iron impurities
2. the current is too high
3. pH value is too high or
too low
4. too less boric acid
1. plus WZn acid zinc
impurity agent
2. lower current density
3. adjust to the range
4. adding boric acid
properly
Bad plating in the low
current region after Adding
potassium chloride, zinc
chloride
1. iron impurities are
brought in
2. copper, lead impurities
are brought in
3. brightener inadequate
1. electrolysis with low
current or add WZn
impurity agent
2. electrolysis with low
current or processing zinc
powder
3. add brightener properly
The plating with low
brightness and appears
fog.
1. brightener inadequate
2. too more organic
impurities
3. too more metal
impurities
1. adding properly
2. large processing
3. large processing or add
WZn impurity agents
Coating blistering, peeling,
black
1. bad pre-treatment 1. to strengthen
pretreatment