1、 FORD LABORATORY TEST METHOD BO 012-01 Date Action Revisions 2001 03 20 Editorial no technical change A. Cockman 1992 07 14 Printed copies are uncontrolled Page 1 of 4 Copyright 2001, Ford Global Technologies, Inc. RESISTANCE OF POLYURETHANE FOAM TO DETERIORATION Application This procedure is used t
2、o measure the resistance to deterioration of polyurethane foam under conditions of high humidity, high temperature and mild pressure. Deterioration on seat padding materials is measured by a change in load deflection of the specimen after the humidity test. Crash pads, visors, arm rests, etc. are co
3、nditioned in the autoclave and then bent over a mandrel and examined for cracking as evidence of deterioration. Apparatus Required Autoclave or Pressure Cooker An autoclave (see illustration) or steam pressure cooker is required for this test. The apparatus shall be provided with a pressure gage, pr
4、essure regulating valve and safety valve. It shall also be equipped with a rack for suspending the test specimens above the water level and shall be large enough to accommodate the 6 by 6 inch test specimens. The steam pressure cooker may be obtained from the Wisconsin Aluminum Foundry Co., Model No
5、 25X. The autoclave shown (Model 999-C) is used at the Body Materials Laboratory. Other equivalent apparatus may be used for this test. Source: Wilmot Castle Company Box 629 Rochester 2, New York Mandrel A 1/4 inch diameter wooden mandrel is required for specimens other than seat pads where small s
6、amples are tested. Oven Mechanical convection at 158 +/- 2 F. FORD LABORATORY TEST METHOD BO 012-01 Page 2 of 4 Copyright 2001, Ford Global Technologies, Inc. Conditioning and Test Conditions All test values indicated herein are based on material conditioned in a controlled atmosphere of 23 +/- 2 C
7、and 50 +/- 5 % relative humidity for not less than 24 h prior to testing and tested under the same conditions unless otherwise specified. Procedure Load Indentation after Aging Seat Pads 1. A specimen of (slab or molded) polyurethane foam 6 by 6 inches by full depth thickness, where possible, is req
8、uired for this test, with the exception of pads exceeding 4 inches in thickness. In this case, the bottom shall be trimmed to provide a pad of 3 - 4 inches in depth. 2. Condition all test specimens for 24 h at 72 +/- 5 F and a relative humidity of 50 +/- 2 %. 3. Place the test specimen on the suppor
9、ting plate of the indenter, apply a preload of 1 lb and determine the height of the test specimen. 4. The specimen shall then be twice deflected to 75 +/- 5 % of the original height, using either rollers or plates as a means of obtaining the deflection. The specimen shall then be allowed to rest for
10、 10 +/- 5 minutes. 5. Deflect the specimen 25 % of the recorded height and, after exactly one minute, read and record the load. 6. Add sufficient distilled water to the autoclave for the 3 h test but keep the water level below the specimen supporting rack. Place the specimens in the autoclave and se
11、curely fasten the top. Set the thermostat control for 216 - 225 F (gage pressure between 1.3 and 4.3 psi), leave the safety valve open and heat until steam is emitted through the ports of the safety valve. The valve shall be closed 2 minutes after the appearance of steam and the time of the test sha
12、ll be started at this point. 7. After 3 h in the autoclave, turn off the heat, release the steam pressure, remove the test specimens and dry for 3 h in a mechanical convection oven at 158 +/- 2 F. 8. Condition the test specimens for at least 2 h and not more than 24 h at 72 +/- 5 F and 50 +/- 2 % re
13、lative humidity. 9. Determine the 25 % compression deflection as in Steps 3 through 5. FORD LABORATORY TEST METHOD BO 012-01 Page 3 of 4 Copyright 2001, Ford Global Technologies, Inc. 10. Calculate and report the aged load indentation as follows: LO - LI x 100 = aged load indentation LO Where LO = o
14、riginal load indentation and LI = load indentation after humidity test Cracking or Deterioration After Aging Crash Pads, Visors, Seat Pads, etc. 1. Cut a section of polyurethane foam 1 by 1 by 3 inches, or as otherwise stated in the material specification, from the assembly, removing any cover stock
15、 2. Condition the test specimen in the autoclave for 3 h as described under Seat Pads. 3. Remove the specimen and allow to recover for 4 h at 72 +/- 5 F. Bend the test specimen 180 around a 1/4 inch mandrel and inspect for cracking or crumbling. If any of the four sides of the test specimen has a s
16、kin where it was foamed into place against the cover stock or mold, this side shall be placed next to the mandrel. Any evidence of cracking is the result of deterioration of the polyurethane foam and shall be reported as a failure. 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. FORD LABORATORY TEST METHOD BO 012-01 Page 4 of 4 Copyright 2001, Ford Global Technologies, Inc. RESISTANCE OF POLYURETHANE FOAM TO DETERIORATION Autoclave
