METAL FINISHING

ALUMINIUM : CHROMATE CONVERSION COATING

What is chromate conversion coating :

Chromate conversion coating is the formation of a chromate layer on aluminium surface .
Chromate conversion coating is apply to passivate the aluminium metal . It may be for corrosion resistant purpose or it may be for a undercoat for organic coating .

HOW TO REDUCE THE COST :

ELECTROPLATERS'S COST CUTTING FACT

A lot of electroplaters doing plating business and complaining that their customer paying very less. it may be true in some cases . If you not able to get the more rate then try to cut down the cost. here are some major  usefull fact , by applying this facts i am sure you may  get some  benefit :

1. ANODE :  Try to keep the maximum level of metal anodes to reduce electricity expenses, If you keep more anodes then you have to give less volts for getting the particular ampere , If you have less anode then you have to give more volt to get the same ampere.If we giving more volt then electricity consumption will be more. In plating process electricity always calculated by ampere not by volt. some example are here :

 Alkaline zinc plating :  20-30 amp per sq feet
 Acid zinc plating      :  15-30 amp per sq feet
Nickel plating           :  30-40 amp per sq feet

2. PRETREATMENT : A lot  of electroplaters don't take the pretreatment process so seriousily . they tried to cut the time of pretreatment to take more production , but at the end of day they are able to take more production with defective coating due to improper pretreatment. actually pretreatment is the base of plating and if base is not good then we can't expect the proper bonding, adhesion, smooth finish,brightness etc.

 By adopting proper pretreatment we can reduce the rejection percentage of final product and can be reduce the plating time also in some cases.
Today's market a lot of cost effective pretreatment chemicals are available , try some of them .

3. WATER RINSE : Again water is the one of cheapest chemicals use by electroplaters. By using proper water rinses we can save the costly chemicals during the process .During the plating process if process in one chemicals (say acidic) but after this process component not rinse proper in the water then this chemicals carry over to the next process and spoil the solution partly and slowly but after some time chemicals contaminent to above the tolerence level. If happen then solution may be spoil or you have to treat them. In both way you have loose the money, time  , loss of production etc. So let us give the proper water rinse to save the chemicals or you can say money.

4. TEMPERATURE : To heat the solutions of plating bath or pretreatment bath we use the heaters. To save the electricity have the proper plan like Nos of heaters or capacity of heaters and auto cut off control to avoid the excess heating etc.

                            "SAVING THE MONEY IS EARNING THE MONEY "

                                                                     

Related Post :

why we do electroplating

passivation

boric acid free acid zinc :a cost cutting process

aluminium acid degreaser

phosphating

Electroless Nickel 

Everything is possible

Winner's Tool Box

10    TIPS    FOR   WINNER

SUCCESS TOOL BOX : KEEP 10 THINGS

In the life every body want to success but very people get success . Some people try but not success due to improper way or improper tools. IF you want to be  successful person then you should Create a success tool box. A successful technician always keep update his tool box but unsuccessful technician always fight with his tools. To create a successful tool box , keep following things in your successful tool box:

1.   Keep Smile Face

2.   Think big   

3.   Burning desire to be a winner

4.   Positive attitude

5.   Develop confidence

6.   Communication

7.   Body language

8.   Patience

9.   Focussed

10.Control anger

                                                          

IT IS BETTER TO WEAR OUT THAN RUST OUT

Common Problems During Plating

During the plating we face many problems during process after many precautions , some are here :

1.  PITTING : 

Pitting come due to hydrogen attack on the base metal or coated metal during acid pickling/Plating in the acid bath .

2.  ROUGHNESS : 

Roughness means rough deposit which come due to foreign particles deposit with metal or coarse deposit due to excess current .

3.  PEEL OFF : 

Peel off  means removing of coated metal due to improper cleaning of base metal etc .

4.  LOW THICKNESS : Less coating

5. LESS SALT SPRAY LIFE OR CORROSION RESISTANCE : Poor corrosion resistance due to poor plating process or wrong process .

        Zinc Plating Process : 

The normal process to be follow in a various stages as given under :

                    Degreasing

                         ↓

                    Water rinse

                         ↓

                    Water rinse

                         ↓

                     Pickling

                         ↓

                    Water rinse

                         ↓

                     Water rinse

                         ↓

                     Zinc plating

                         ↓

                    Water rinse

                         ↓

                      Bright dip 

                         ↓

                    Water rinse      

                         ↓

                     Passivation

                         ↓

                     Water rinse

                         ↓

                    Water rinse

                         ↓

                       Dry

NICKEL PLATING PROCEDURE ON ZINC DIE CAST COMPONENT

1.       DEGREASING

2.       WATER RINSE

3.       WATER RINSE

4.       ACTIVATION

5.       WATER RINSE

6.       CYANIDE COPPER STRIKE

7.       WATER RINSE

8.       SULPHURIC ACID DIP  5%

9.       WATER RINSE

10.     ACID COPPER PLATING

11.     WATER RINSE

12.     WATER RINSE

13.     NICKEL PLATING

14.     WATER RINSE

15.     WATER RINSE

16.     CHROME PLATING

17.     WATER RINSE

18.     WATER RINSE

19.     HOT WATER RINSE

20.     DRY

                                                                     

     

TIN PLATING : 

HOW TO INCREASE SOLDERABILITY SHELF LIFE ?


Normally we do tin plating for soldering and contact purpose .Here I am writing about tin plating on copper and copper alloys only . When we do soldering After tin plating , Soldering will be very nice . Then we assessed the tin plating part is good . Same parts we pack & supply or keep in store for some weeks or months . After that customer found that tin plated component got discolour and soldering not getting proper . Then they start blaming to platers for faulty tin plating . In this situation parts manufacturer and plater both will be in problem.

 When plater did the tin plating that time soldering was good but after some time soldering failed . It means soldering shelf life of components is very less .

REASONS OF PROBLEM 

 Normally this problem occur due to copper diffusion and  intermetallic layer formation between tin and copper , which can grow to reach the surface of tin coating and this  will reduce the solderability shelf life . 

NICKEL UNDERCOAT IS THE SOLUTION 

Copper diffusion and Intermetallic layer formation between tin and copper is very fast . To enhance the solderability shelf life of components nickel undercoat between copper and tin is must . Intermetallic layer formation between tin and nickel  is slow compare to tin and copper .

RELATED POSTS :

TIN PLATING
TIN PLATING : EFFECTS OF BRIGHTENERS & ADDITIVES

why we do electroplating