1、 FORD LABORATORY TEST METHOD AQ 002-01 Date Action Revisions 2001 01 31 Revised Editorial no technical change A. Cockman 2000 04 19 Editorial no technical change A. Cockman 1992 05 01 Printed copies are uncontrolled Page 1 of 7 Copyright 2001, Ford Global Technologies, Inc. CONTROL TESTS FOR PHOSPHA
2、TE COATING PROCESS Application These test methods are used where applicable to check the concentration of the solutions used in the phosphate coating process described in the Material Standards PL 53-07, PL 53-09, and PL 53-32. The analytical techniques listed which utilize a “point system“ for the
3、titration of solutions is designed to provide for simple conversion of results in points to concentration of a solution. This procedure eliminates the need for relatively complicated manipulations of gram equivalent weights, specific gravity, etc. If it is necessary to express concentrations in actu
4、al percentage concentrations this may be accomplished by substituting into the following conversion formula. % unknown = mL titer used x normality x factor x 100 wt. sample Solutions Required See Ford Laboratory Test Method AZ 2-1 for preparation of solutions and indicators. Standard Sodium Hydroxid
5、e 0.1 N Reagent No. 1 Standard Hydrochloric Acid 0.1 N Reagent No. 4 Standard Potassium Permanganate 0.042 N Reagent No. 9 Use 1.34 g and dilute to 1 liter or take 420 mL of 0.1 N solution and dilute to 1 liter. titration factor = normality 0.042 Standard Potassium Ferrocyanide Reagent No. 12 Standa
6、rd Ferrous Sulfate Solution 0.1 N Reagent No. 10 Standard Sodium Thiosulfate Solution 0.1 N Reagent No. 14 Standard Potassium Dichromate Solution 0.1 N Reagent No. 15 Indicators Phenolphthalein Reagent No. 101 Brom Cresol Green Reagent No. 108 Brom Phenol Blue Reagent No. 109 Diphenylamine Reagent N
7、o. 110 Iron Test Paper Reagent No. 111 Starch Solution Reagent No. 113 Orthophenanthroline Reagent No. 114 FORD LABORATORY TEST METHOD AQ 002-01 Page 2 of 7 Copyright 2001, Ford Global Technologies, Inc. Titrating and Indicator Solutions Supply List Prepared solutions required for control tests may
8、be obtained from the Amchem Products, Inc. or Parker Rust Proof Co. when ordered by their respective numbers as shown: Standard Solutions Amchem Parker Sodium Hydroxide 0.1 N 11 11 Hydrochloric Acid 0.1 N 20 - Potassium Permanganate 0.042 N 15 15 Sulphuric Acid 0.1 N - 20 Potassium Ferrocyanide (1 g
9、 = 0.015 g/Zn) 16 - Sodium Thisulfate 0.1 N 31 - Ferrous Sulfate 0.1 N - 31 Potassium Dichromate 0.1 N - 30 Indicators Amchem Parker Phenolphthalein 3 3 Brom Cresol Green 2 2 Brom Phenol Blue 10 11 Diphenylamine 7 7 Indicator Paper Iron 2005 17 Orthophenanthroline - 12 Conditioning and Test Conditio
10、ns All test values indicated herein are based on material conditioned in a controlled atmosphere of 23 +/- 2 C and 50 +/- % relative humidity for not less than 24 h prior to testing and tested under the same conditions unless otherwise specified. Procedure Test A Cleaner Control Free Alkali 1. Pipet
11、 10 mL of sample into a 150 mL Erlenmeyer flask. 2. Add 5 drops of phenolphthalein indicator. 3. Titrate with 0.1 N HCl until solution changes from pink to colorless. 4. mL of HCl used = free alkali value. FORD LABORATORY TEST METHOD AQ 002-01 Page 3 of 7 Copyright 2001, Ford Global Technologies, In
12、c. Total Alkali 1. Pipet 10 mL of sample into a 150 mL Erlenmeyer flask. 2. Add 10 drops of brom cresol green indicator. 3. Titrate with 0.1 N HCl until color changes from purple red to yellow. 4. mL of 0.1 N HCl indicates total alkali value. Test B Rinse Water Control (After Alkaline Cleaning) Tota
13、l Alkali 1. Pipet 10 mL of the rinse water into a 150 mL Erlenmeyer flask. 2. Add 5 drops of brom cresol green indicator. 3. Titrate with 0.1 N HCl to yellow end point. Report mL of HCl as total alkali value 4. If solution turns yellow after addition of indicator, discard sample and proceed as follo
14、ws: (See Note) (a) Pipet 10 mL of sample into a 150 mL Erlenmeyer flask. (b) Add 5 drops of phenolphthalein indicator. (c) Titrate with 0.1 N NaOH to a pink color. (d) mL of 0.1 N NaOH = points total acid Note: This is an abnormal condition and indicates that phosphate solution is getting into the r
15、inse water, possibly through a misdirected nozzle. Test C Phosphate Coating Control M1178C or M3B1 with M13844 Accelerator Total Acid 1. Pipet 10 mL of sample into a 150 mL Erlenmeyer flask. 2. Add 5 drops of phenolphthalein indicator. 3. Titrate with 0.1 N NaOH to the development of a pink color. 4
16、. mL of 0.1 N NaOH = points total acid. FORD LABORATORY TEST METHOD AQ 002-01 Page 4 of 7 Copyright 2001, Ford Global Technologies, Inc. Free Acid 1. Pipet 10 mL of sample into a 150 mL Erlenmeyer flask. 2. Add 3 drops of brom phenol blue indicator. 3. Titrate with 0.1 N NaOH to a color change from
17、yellow to light blue. 4. mL of 0.1 N NaOH used = free acid points. Accelerator Test Before testing for the amount of accelerator, dip a strip of iron test paper in phosphate solution. If the paper turns pink, it is an indication that no accelerator is present. Small additions of accelerator should b
18、e made to the phosphate solution tank until no change in color of a fresh indicator paper occurs. When no change in color of the test paper appears, proceed to determine the amount of accelerator as follows: 1. Pipet 25 mL of the phosphate solution into a 150 mL Erlenmeyer flask. 2. Add 10 20 drops
19、of dilute C.P. H2SO4 (1:1). 3. Titrate with standard 0.042 N KMnO4 drop by drop while swirling; until a persistent pink color is obtained which remains for 10 seconds. 4. mL of KMnO4 x titration factor = points of accelerator present. Test D Phosphate Coating Control M1171B with M1172B Accelerator A
20、ccelerator Test 1. Pipet 10 mL of the filtered bath into a 350 mL Erlenmeyer flask. 2. Dilute to 100 mL with water. 3. Add 10 mL of dilute H2SO4 (1:1). 4. Titrate to a permanent pink color with 0.042 N. KmnO4. 5. The number of mL of KmnO4 used x titration factor is the accelerator concentration. (Sa
21、ve Sample for phosphate test.) FORD LABORATORY TEST METHOD AQ 002-01 Page 5 of 7 Copyright 2001, Ford Global Technologies, Inc. Phosphate Test Based on Zinc Content of Bath 1. Add 0.5 mL of standard KmnO4 (0.042 N) to the sample just titrated for accelerator. 2. Add 3 4 drops of diphenylamine indica
22、tor. 3. Titrate with standard potassium ferrocyanide to a green end point as follows: Add 2 drops of titrating solution at a time, swirling 5 seconds between additions. Continue until the color of the solution changes to a light blue and then a violet. At this point add only 1 drop of the titrating
23、solution at a time, swirling for 30 seconds between additions. The end point is reached when a light green color persists which does not revert to a violet color on stirring. The end point is a very sharp if instructions are followed exactly. 4. The number of mL potassium ferrocyanide used x factor
24、is the concentration of the phosphate coating based on the zinc content. Test E Chromic Phosphoric Control Free Acid 1. Pipet 25 mL of test solution into a 150 mL Erlenmeyer flask. 2. Add 4 drops of brom cresol green indicator. Note: If the color of the sample turns from yellow to green after adding
25、 indicator, it indicates that no free acid is present; that additional chromic-phosphoric acid M13879 should be added to the rinse tank and another test made. 3. If the solution remains yellow, titrate to a green color with 0.1 N NaOH. Note: Save sample for Total Acid Test. 4. mL of 0.1 N NaOH used
26、indicates the points of free acid present. Total Acid 1. Add 5 drops of phenolphthalein to the sample used in the Free Acid Test and continue titrating with 0.1 N NaOH to a violet color which will last for 15 seconds. 2. The total number of mL of 0.1 N NaOH used in the Free Acid and Total Acid Tests
27、 is points of total acid present. FORD LABORATORY TEST METHOD AQ 002-01 Page 6 of 7 Copyright 2001, Ford Global Technologies, Inc. Test F Babcock Number Zinc Phosphate for Cold Forming PL 53-32 This test requires the use of a conical graduate, 100 mL Cassia flask, and a water bath. 1. Measure 50 mL
28、of the holt lubricant (190 +/- 5 F) into a conical graduate. 2. Pour into a 100 mL Cassia flask, rinsing the graduate into the flask with 20 25 mL of hot water. 3. Place the flask in a boiling water bath for 3 5 minutes. 4. Add 10 mL of dilute H2SO4 (1:1) and swirl the flask to mix thoroughly. 5. Pl
29、ace in the water bath and, after 15 minutes, add hot boiled water to bring the oily layer into the neck of the flask. 6. After 5 minutes, when the oily layer has separated sharply, take the readings of the lower and upper edges of the clear oily column in the neck while the flask is still in the wat
30、er bath. 7. The difference between the two readings is reported as the Babcock number. Test G Hexavalent Chromium Two optional methods are shown Method No. 1 for Amchem Products material and Method No. 2 for Parker Rust Proof material. Method No. 1 1. Pipet 25 mL of the sample into a 250 mL iodimetr
31、ic flask and dilute to 100 mL with distilled water. 2. Add approximately 1 g of potassium idodide and agitate until dissolved. 3. Add 15 mL of HCl (conc.) in 5 mL increments to the lip of the flask and raise the stopper slightly after each addition to allow the acid to run into the flask. 4. Rinse t
32、he lip of the flask several times with distilled water and replace the stopper. 5. After 1 minute, titrate the solution with 0.1 N sodium thiosulfate (Reagent No. 14) until a straw color is obtained. 6. Add 3 5 mL of soluble starch solution (Indicator No. 113) and continue the titration until the bl
33、ue-black color disappears. 7. The total number of mL of titrating solution used is the points of hexavalent chromium present. FORD LABORATORY TEST METHOD AQ 002-01 Page 7 of 7 Copyright 2001, Ford Global Technologies, Inc. Method No. 2 1. First be sure that the free acid is in the operating range. 2
34、. Pipet 25 mL of sample into a 250 mL beaker and add 25 mL of H2SO4 (1:1). 3. Add 35 mL of distilled water and 2 drops of orthophenanthroline (Indicator No. 114). 4. Titrate with 0.1 N ferrous sulfate (Reagent No. 10) until the solution changes through blue to a reddish brown color. Calculate points
35、 of hexavalent chromium (Parcolene 8) as follows: Points = mL 0.1 N FeSO4 x C (correction factor) Note: The 0.1 N FeSO4 is not stable and must be standardized weekly to determine its correction factor “C“ as follows: (a) Pipet 10 mL of 0.1 N potassium dichromate solution (Reagent No. 15) into a 250
36、mL beaker. (b) Add 25 mL of H2SO4 (1:1), 50 mL of distilled water and 2 drops of orthophenanthroline (Indicator No. 114). (c) Titrate with 0.1 N FeSO4 solution until the color changes through blue to a reddish brown color. Correction Factor “C“ = 10 (mL dichromate) mL of ferrous sulfite used Chemicals, materials, parts, and equipment referenced in this document must be used and handled properly. Each party is responsible for determining proper used and handling in its facilities.
