Deveco Tri 106

High corrosion trivalent chromate coating

Deveco TRI 106 is a mid-corrosion chromate at 2%.  It has a pleasing blue-bright coating on electroplated zinc that delivers up to 48 hours protection to white corrosion in salt fog testing.

Deveco TRI 106 is a high-corrosion chromate at 5%. It imparts a clear, colorless coating on electroplated zinc and zinc alloys that exceeds 144 hours protection on zinc plating to white corrosion in salt fog testing. When used in conjunction with our Tri-color concentrates, (i.e. Deveco TRI-GOLD Conc. as a yellow chromate), the corrosion protection is further enhanced.

Deveco TRI 106 is a ultra high-corrosion chromate at 10%. it imparts a clear, colorless coating on electroplated zinc and zinc alloys that exceeds  250 hours protection on zinc plating to white corrosion in salt fog testing. When used in conjunction with any of our Tri-color concentrates, the corrosion protection is further enhanced.

Deveco TRI 106 is an easy to use one-part liquid product, which is applied by conventional immersion techniques.

OPERATING PARAMETERS

Blue-bright, Mid-corrosion	Recommended	Range
Deveco TRI 106	2% by volume	1.5 to 3 % by volume
Temperature	70 ^oF	70 to 90 ^oF
Time	40 seconds	30 to 45 seconds
PH	2.0	1.8 to 2.6

Clear, High-corrosion	Recommended	Range
Deveco TRI 106	5% by volume	3 to 6 % by volume
Temperature	80 ^oF	75 to 85 ^oF
Time	40 seconds	30 to 45 seconds
PH	2.0	1.8 – 2.6
Max Zinc cont. limit	10 g/l (10,000 PPM)
Max Iron cont. limit	250 PPM

Clear, Ultra High-corrosion	Recommended	Range
Deveco TRI 106	10.5% by volume	9 to 12 % by volume
Temperature	80 ^oF	75 to 85 ^oF
Time	40 seconds	30 to 45 seconds
PH	2.0	1.8 – 2.6
Max Zinc cont. limit	25 g/l (25,000 PPM)
Max Iron cont. limit	500 PPM

To lower the pH, use concentrated Nitric Acid.

To raise the pH, use 50% Caustic Soda.

Deveco TRI 106

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TYPICAL CYCLE

1. Zinc Plate

2. Rinse

3. Nitric Acid Predip (0.5 – 1.0% by volume)      

4. Rinse

5. Deveco TRI 106

6. Cold Water Rinse

7. Hot Water Rinse

8. Dry (or apply a subsequent post-dip)

Ø As with any chromate, the plating bath must be in good operating order, within proper parameters and without excessive trace metals and/or organic contamination to get satisfactory corrosion protection from the trivalent chromate film.

o Decant or dump the bath to maintain the Zinc and Iron concentrations below the recommended limits when the chromate film must meet salt spray requirements.

Ø In the normal new make-up of Deveco TRI 106, the pH will usually be below the operating norm.

Ø A Nitric Acid pre-dip is recommended for zinc plating, to increase the life of the chromate, particularly when plated in an alkaline zinc electrolyte.

ANALYSIS of TRI 106 Chromate Solution:

1. Add a 20 ml sample of the chromating solution into a flask.

2. Add 50 to 100 mls DI or distilled water.

3. Add 1 to 2 mls of phenolphthalein indicator.

4. Titrate with 1.0 N Sodium Hydroxide to a violet-blue end-point. (pH 8.2)

NOTE:  The sample will become cloudy before the end-point is reached.

Calculation:     Mls 1.0 N Sodium Hydroxide x 2.8 = % by volume of Deveco TRI 106.

Analyze the chromate solution for Zinc and Iron by AA analysis

CAUTION:

Deveco TRI 106 is a corrosive liquid and should be handled with caution. 

Please refer to the MSDS before using the product.

DISCLAIMER:

The information presented herein, while not guaranteed, is to the best of our knowledge true and accurate.  No warranty or guarantee expressed or implied is made regarding the performance of any products, since the manner of use is beyond our control.  No suggestion for product use or anything contained herein shall be construed as recommendation for its use in infringement of any existing patent and we assume no responsibility or liability for operations which do infringe any such patents.  The above includes confidential and proprietary information of Deveco Corporation and is furnished to you for your use solely on products or processes supplied by us to you.

Product data sheets/KR114                                          Effective. Date: 9-24-04                                                 Supersedes  7-12-04

Deveco TRI 106 Analysis (Alternative Method)

Ø Pipette 10 mls of sample into a 250 ml flask

Ø Add about 50 mls DI water

Ø Add 2 to 3 grams Ammonium Persulfate (NH₄)₂S₂O₈

- (Also known as Ammonium Peroxydisulfate)

Ø Heat to boiling for 1 hour, adding DI water as needed

Ø Remove from heat and cool to near room temp.

Ø Add about 2 grams Ammonium Bifluoride (NH₄HF₂ )

Ø Add about 30 mls of 50% HCl Hydrochloric Acid

Ø Add about 10 mls of 10% KI Potassium Iodide

Ø Titrate with 0.1 N Sodium Thiosulfate until solution begins to lighten

Ø Add about 5 mls Starch Indicator solution

Ø Continue to Titrate with 0.1 N Sodium Thiosulfate – end pt: blue à clear

Mls 0.1 N Sodium Thiosulfate  x  1.22 = % Deveco TRI 106