1、 FORD LABORATORY TEST METHOD BI 112-02 Date Action Revisions 2001 03 19 Revised Editorial no technical change A. Cockman 1990 02 12 Printed copies are uncontrolled Page 1 of 2 Copyright 2001, Ford Global Technologies, Inc. TUKON HARDNESS OF PAINT Application This method is used to determine the micr
2、ohardness of paint and is performed by indenting the paint film with a standard Knoop indenter by application of a 25 g load. Apparatus Required Microhardness Tester Tukon Models 200 and 300, or equivalent. Source: Rockwell Hardness Testers Sandy Lane Stourport-on-Severn Worcestershire, DY133QA, Eng
3、land or Wilson Instrument Division of SPM Corp. P.O. Box 3006, 20 Commerce Park Milford, Connecticut 06460 U.S.A. Paint Thickness Tester Refer to FLTM BI 117-01, Thickness Measurement of Paint Films. Conditioning and Test Conditions All test values indicated herein are based on material conditioned
4、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 specified. Procedure 1. Prepare the panel as described in the applicable Engineering Material Specification. Note: Minimum dry film
5、thickness 35 microns. FORD LABORATORY TEST METHOD BI 112-02 Page 2 of 2 Copyright 2001, Ford Global Technologies, Inc. 2. After preparation, condition the panel as required by the applicable Engineering Materials Specification. If not specified in the Engineering Material Specification, condition th
6、e panel for 24 h minimum a 23 +/- 2 C and 50 +/- 5 % relative humidity and immediately test the panel. 3. On the area of the panel that is to be used for hardness tests, film thickness determinations must be made (FLTM BI 117-01) to ensure that film thickness on any one panel does not vary more than
7、 2.5 microns; for different panels, 7.5 microns variation is permitted. 4. Rigidly attach the panel to the movable stage of the hardness tester so that the paint surface being measured is at right angles to the indenter. The panel must be mounted so that it will not move in any direction during the
8、course of the test. 5. By adjusting the movable micrometer stage and by focusing the microscope on to the panel, select an area where the film thickness has been measured and the paint film is free from roughness or other surface irregularities. When this area has been selected, place it under the i
9、ndenter by sliding the movable stage to the proper forward position. 6. Activate the instrument which will then mechanically apply the required 25 g load. Time the load application which is to be maintained for 18.0 +/-0.5 s. Note: If the equipment used is not automatic, consult manufacturers direct
10、ions for procedure to apply load. 7. Slide the movable stage back into its original position which will result in the indentation being in the microscope field. This step must be performed immediately after Paragraph 6. 8. Focus the microscope so that the extremities of the long diagonal impressions
11、 are sharp and clear. With the Filar micrometer eyepiece, measure the length of the indentation. 9. Convert the Filar length of the impression by multiplying by the appropriate factor for the microscope objective used. Evaluation A minimum of five hardness impressions shall be made and the results a
12、veraged. If a conversion table is not available, K.H.N. may be calculated as follows: Knoop Hardness Number = L l2 x Cp Where: L = Load in kg applied to the indenter l = Length of long diagonal of indentation in mm Cp = Indenter constant = 7.028 x 10-2 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.
