Deveco 407

Deveco 407 is a golden chromate coating for electroplated zinc and electroplated cadmium.  The coatings produced have excellent corrosion resistance and are an excellent base for paint.

MAKE-UP AND CONTROL:

            Deveco 407                                           0.5 to 1.5%

            Time                                                     15 to 45 seconds

            Temperature                                          60 to 90°F

            pH range                                               1.4 to 1.8

Prior to using the chromate, a 0.25% nitric acid dip is recommended.

ANALYTICAL CONTROL - Hex-chrome titration:

1. Pipette 10 mls sample of chromate solution into a 250 mls flask.

2. Add 100 mls D.I. water.

3. Add 2 grams of Ammonium Bifluoride.

4. Add 30 mls 50% Hydrochloric Acid.

5. Add 10 mls of 10% Potassium Iodide solution.

6. Titrate with 0.1N Sodium Thiosulfate to light straw color.

7. Add 5 mls of 1% Starch solution.

8. Continue titration with 0.1 N Sodium Thiosulfate.  End-point: blue à colorless.

a. (Absence of blue should persist for 30 seconds).

Calculation:  Mls Thiosulfate x 0.12 = % Deveco 407

Deveco 407 does not require analytical control for effective chromate deposition.  It can also be controlled by pH. 

Ø If the pH falls below 1.4 sloughing will occur. 

Ø If the pH rises above 1.8 the color of the chromate will be too light or will not be visible at all.

Ø If the pH rises above 1.8 lower the pH by using a hand held pH meter and adding Deveco 407 to the tank until the pH falls within the operating range. 

Ø If the pH drops below 1.4, contact Deveco.

CAUTION:

This product contains chromates and is acid in nature.  Contact of salts or solution with skin or eyes should be avoided.  In case of contact, flush contaminated area with a large amount of water.  When handling this product, protective clothing, i.e. rubber apron, gloves, boots, and goggles should be worn.

Read Material Safety Sheet before using this product.

EQUIPMENT: Deveco 407 solutions require polyethylene, stainless steel, or koroseal lined tanks.

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 Sheet/KR062                                                     Effective Date: 1-4-06                                             Supersedes: 4-30-98