1、 FORD LABORATORY TEST METHOD EU-AQ 006-01 Date Action Revisions 2001 01 31 Revised Editorial no technical change A. Cockman 2000 04 20 Editorial no technical change A. Cockman 1993 10 21 Printed copies are uncontrolled Page 1 of 2 Copyright 2001, Ford Global Technologies, Inc. CONTROL TEST - CHROMAT
2、E ON PHOSPHATE COATED OR PLATED PARTS Application This method is used to check phosphate coated or plated parts for the presence of hexavalent chromate. Chemicals and Apparatus Required Diphenylcarbazide 1 % solution in ethyl alcohol. Phosphoric Acid 4 % by volume Distilled or Demineralised Water De
3、greasing Reagent (Carbon Tetrachloride or Petroleum Ether) Kessler Tube 25 mm dia x 150 mm long. Conditioning and Test Conditions All test values indicated herein are based on material conditioned in a controlled atmosphere of 23 +/- 2 C and 50 +/- 5 % relative humidity for not less than 24 h prior
4、to testing and tested under the same conditions unless otherwise specified. Procedure 1. Take sufficient number of parts in the “as used condition“ to give a test surface area of 50 +/- 10 cm2 (see BS 3382 1961, Parts 1 and 2). 2. Degrease the parts using carbon tetrachloride or petroleum ether to r
5、emove all traces of oil or grease. FORD LABORATORY TEST METHOD EU-AQ 006-01 Page 2 of 2 Copyright 2001, Ford Global Technologies, Inc. 3. Suspend the parts in 200 mL of distilled or demineralised water at 100 C and simmer for 5 minutes. 4. Remove parts from the water, cool to 23 +/- 2 C, then three
6、quarters fill a Kessler tube with this solution, add 5 mL of the 4 % phosphoric acid followed by 2 mL of the 1 % diphenylcarbazide solution. Shake and allow to stand for 5 minutes. 5. Run a blank test using the relevant solutions. 6. After allowing the test and blank solutions to stand for 5 minutes
7、 to develop a stable colour complex, compare the colours developed in the solutions against a white background. Evaluation No colour difference between blank and test solutions indicates absence of chromate. Pale lilac to purple colouration in test solution indicates presence of chromate. Colour density is indicative of amount of chromate present. Chemicals, materials, parts, and equipment referenced in this document must be used and handled properly. Each party is responsible for determining proper use and handling in its facilities.
