1、 FORD LABORATORY TEST METHODBI 124-01Date Action Revisions 2005 03 22 Revised Updated Procedure and revised Film Thickness Gauge M. Kelly 2001 11 14 Revised Rev Apparatus and Procedure M. Kelly, K. Bruley 1999 01 26 Printed copies are uncontrolled Copyright 2005, Ford Global Technologies, LLC Page 1
2、 of 4 FILIFORM CORROSION TEST Application This procedure is used to evaluate comparatively the filiform corrosion resistance of fully or partially painted, clear coated aluminum wheel surfaces. Apparatus Required Controlled Atmosphere Chamber For construction of the controlled atmosphere chamber ref
3、er to Figure 1. Large round jar (a) or desiccator (b): (a) Jar, cylindrical, plain, Pyrex brand, O.D. 305 mm, height 305 mm. (b) Desiccator, body only, Pyrex brand, 250 mm size. Polycarbonate Cover 6 mm thick to fit jar or desiccator Small Gearmotor Model CA, 150 to 400 rpm, or equivalent. Source: H
4、urst Mfg. Corp. P. O. Box 326 Princeton, Indiana 47670-0326 Tel: (812) 385-2564 Fax: (812) 386-7504 Note: Gearmotor should be reversible. During operation of the test, more uniform results are obtained if the stirring rotor direction is changed about every five minutes. This can be done automaticall
5、y with an external timer/single pole-double throw switch arrangement such as: Source: Model CMS Industrial Timer Corporation U.S. Highway 287 Parsippany, NJ 07054 Polycarbonate Sheet Thickness: 1.6 mm or less Polycarbonate Rod 50 mm length, 18 mm diameter, for rotor Wide Mouth Dish For HCl; 100 mm w
6、atch glass FORD LABORATORY TEST METHODBI 124-01Printed copies are uncontrolled Copyright 2005, Ford Global Technologies, LLC Page 2 of 4 Scriber Carbide Tip, Model 90C Sources: Aircraft Specialties, Inc. (#90C) 415-T Howard St. P. O. Box 98 Lapeer, Michigan 48446 Tel: (810) 664-2981 Fax: (810) 664-2
7、730 GTS (#CM88) 12015 Telegraph Detroit, Michigan 48239 Tel: (313) 531-7666 Film Thickness Gauge Oxford Instrument or equivalent Model CMI700-ED51 Source: Coating Measurement 945 Busse Road. Elk Grove Village, IL 60007 Tel: (847) 439-4404 ext 302 Fax: (847) 439-4425 Email: Weather-Ometer Controlled
8、 Irradiance Water-cooled Xenon Arc Apparatus per SAE J1960. Source: Atlas Electric Devices Company 4114 North Ravenswood Avenue Chicago, Illinois 60613 Tel: (773) 327-4520 Environmental Cabinet Temperature/Humidity Chamber with 24-h recorder or equivalent Source: Thermotron Industries 291 Kollen Par
9、k Drive Holland, Michigan 49423 (616) 392-1492 Materials Required Distilled Water or Deionized Water 20 micro ohms/cm at 25 C maximum conductivity (ASTM D 1125) Hydrochloric Acid Concentrated, 12N minimum FORD LABORATORY TEST METHODBI 124-01Printed copies are uncontrolled Copyright 2005, Ford Global
10、 Technologies, LLC Page 3 of 4 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 to testing and tested under the same conditions unless otherwise sp
11、ecified. Procedure Preparation of Aluminum Wheels: 1. Cut the back rim off each wheel and section the wheel face into six equal pie-shaped pieces. Samples for test should be handled with care to prevent scratches and digs on surfaces. Wash parts in water to remove dirt and contamination and note any
12、 obvious handling marks. 2. Measure the clear coat thickness (per FLTM BI 117-01) on the face of each pie section (minimum of four locations). 3. Expose each section to accelerated weathering in a controlled irradiance water-cooled Xenon arc apparatus (per SAE J1960) for 400 h. 4. If the wheel desig
13、n permits, scribe through the coating on the flange, spoke and hub areas of the wheel sections. Samples should be scribed per SAE J 2634. The scribe tool should be applied in such a way that it ensures penetration into the base metal substrate but avoids excessive pressures that would cause base met
14、al deformation. Gently brush off any excess debris. Use a microvolt meter (or equivalent) to verify conductivity of the base metal and removal of the coating by the scribing tool. 5. Add 195 mL of distilled or deionized water directly to the bottom of the chamber. 6. Add 5 mL of concentrated hydroch
15、loric acid (12N minimum) to the 100 mm watch glass and centrally place the watch glass on the bottom of the chamber. (NOTE: Fresh acid should be used for each new group of samples exposed.) 7. Place each wheel section, with the scribes facing the acid containing watch glass, in the controlled atmosp
16、here chamber. 8. Replace lid, turn on motor and allow to remain at 23 +/- 2 C for 1 h. If testing is conducted under a vented hood, do not use the exhaust fan during the inoculation period. 9. Remove each wheel section from the controlled atmosphere chamber at the end of 1 h; DO NOT rinse. Place dir
17、ectly in environmental cabinet with scribed surfaces facing upward. The temperature within the cabinet shall be controlled to 38 +/- 2 C with the relative humidity controlled to 80 +/- 3%. Evaluation of Aluminum Wheel Sections 1. Visually inspect samples weekly (168 hour intervals), if appropriate,
18、for filiform corrosion. Measure and record filiform corrosion growth from the scribe, as well as any sharp edge of the sample (such as window openings and ribs). Disregard any filaments from the end of the scribe lines. 2. Remove the samples from the environmental cabinet as outlined in the applicab
19、le Engineering Material Specification. FORD LABORATORY TEST METHODBI 124-01Printed copies are uncontrolled Copyright 2005, Ford Global Technologies, LLC Page 4 of 4 3. Record the total hours in which each sample had remained in the environmental cabinet. A log is required to record inspection times,
20、 measurement of filiform corrosion growth and in-and-out dates of each sample. 4. Except for the filaments at the scribe ends, measure filaments from each scribe line and report the average. A maximum of one filament over 1.6 mm (for clear coated only surfaces) or 0.8 mm (painted and clear coated su
21、rfaces) in length may be excluded in the average. Measure the filaments using a Micro-Vu video edge detector, model ED-51, or equivalent. 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. FILIFORM CORROSION TEST DETAILS OF CHAMBER CONSTRUCTION Figure 1
