FORD FLTM BQ 007-2-2000 ACID DISSOLUTION TEST FOR DECORATIVE ALUMINUM PARTS.pdf

1、 FORD LABORATORY TEST METHOD BQ 007-02 Date Action Revisions 2000 08 10 Editorial no technical change A. Cockman 19 92 08 05 Printed copies are uncontrolled Page 1 of 3 Copyright 2000, Ford Global Technologies, Inc. ACID DISSOLUTION TEST FOR DECORATIVE ALUMINUM PARTS Application This procedure descr

2、ibes an accelerated test for determining the resistance to blushing of anodized films on aluminum parts. Scope This test method measures the resistance of the anodic film to blushing by exposing the test sample to a chromic - phosphoric acid solution at a specified temperature for a precise period o

3、f time, and calculating the fractional weight loss as an “ADT Rating“. Equipment Required Analytical Balance Mettler H10 or equivalent* VWR Cat. No. 11269 - 303. Timer or Stopwatch Hot Plate Thermolyne or equivalent* VWR Cat. No. 33930 - 020. Thermometer VWR Cat. No. 61032 - 022* (Celsius) or equiva

4、lent. Solvent Acetone. Light Section Microscope See FLTM BQ 010 - 01. Beakers 1 and 4 L. VWR Cat. No. 13912 - 284, 13912 - 364*, or equivalent. *Source: VWR Scientific P.O. Box 187 Allen Park, MI 48101 FORD LABORATORY TEST METHOD BQ 007-02 Page 2 of 3 Copyright 2000, Ford Global Technologies, Inc. S

5、olution Preparation Chromic-Phosphoric Acid Solution 1. Dissolve 80 g of technical grade chromic acid (CrO3 ) in 3.5 L of distilled water in 4 L beaker. 2. Add 140 mL of 85 % orthophosphoric acid. 3. Add distilled water to bring solution level to 4 L. Note: This solution may be used until 1 g/L of a

6、nodic coating has been dissolved. Stripper Solution Dissolve 35 mL of 85 % ortho phosphoric acid and 20 g of chromic acid per L of distilled water. Conditioning and Test Conditions All test values indicated herein are based on material conditioned in a controlled atmosphere of 23 +/ - 2 C and 50 +/

7、- 5 % relative humidity for not les s than 24 h prior to testing and tested under the same conditions unless otherwise specified. Procedure 1. Cut test specimen approximately 7.5 x 15 cm from the sample part. If the part is smaller than 3 x 6 inches, the test specimen shall be as large a s possible.

8、 Remove loose particles from the cut edges with file or knife. 2. Remove any paint, soil, vinyl and finger prints with solvent. 3. Determine the anodic film thickness with a light section microscope. See FLTM BQ 010 - 01 for method. Alternate ly, if a destructive thickness test is used, a suitable s

9、ize test specimen shall be cut from the sample part. 4. Weigh part to be tested on an analytical balance and record weight as W 1 5. Immerse the test specimen in the chromic - phosphoric acid solutio n for exactly 15 minutes with continuous stirring. The temperature must be maintained within the lim

10、its of 37.2 - 38.3 C during this time. Time, temperature and stirring control are critical in assuring accuracy and repeatability in this step. 6. Remov e specimen from solution, rinse in warm running tap water, rinse in acetone and allow to air dry 5 minutes. FORD LABORATORY TEST METHOD BQ 007-02 P

11、age 3 of 3 Copyright 2000, Ford Global Technologies, Inc. 7. Weigh specimen on an analytical balance and record weight as W 2. 8. Immerse specimen in the stripper solution for 15 minutes at 82 - 93 C. Note: This solution may be used until it fails to remove all the anodic coating. This can usually b

12、e determined by observation. Any coating remaining will show up as a dull white film on a bright metal surface. 9. Remove specimen, rinse in warm runnin g tap water, rinse in acetone and air dry for 5 minutes. 10. Weigh specimen on analytical balance and record weight as W3 11. Calculate “A.D.T.“ ra

13、ting as follows: (W1 W2 ) x 200 t = ADT rating W1 W3 Where t = coating thickness in mils 12. Report results as required in Engineering Specification. Chemicals, materials, parts, and equipment referenced in this document must be used and handled properly. Each party is responsible for deterandling in its facilities.