1、 FORD LABORATORY TEST METHOD EU-BO 012-01 Date Action Revisions 2001 03 27 Revised Editorial no technical change A. Cockman 1994 02 28 Printed copies are uncontrolled Page 1 of 3 Copyright 2001, Ford Global Technologies, Inc. DETERIORATION OF POLYURETHANE MATERIALS AFTER HUMIDITY AGEING Application
2、This method is used to determine the resistance to deterioration of materials based on polyurethane, e.g. polyurethane foam and polyurethane coated textiles after humidity ageing at high temperature and mild pressure. The percentage change in the physical characteristics of the materials under test
3、e.g. tensile strength, elongation at break, compression set and compression load deflection are determined. Where possible the test must be performed on the same specimen before and after ageing (e.g. compression load deflection). Apparatus Required Mechanical Convection Oven Capable of maintaining
4、a temperature of 70 +/- 1 C. Autoclave Capable of maintaining a temperature within 3 C in the range of 100 C to 125 C, capable of withstanding a pressure of 150 kN/m2, provided with a “minimum water fuse alarm“, pressure regulating valve, safety valve, and must be equipped with a screen above the wa
5、ter level for carrying the test specimens. Demineralised Water For the autoclave. 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
6、tested under the same conditions unless otherwise specified. FORD LABORATORY TEST METHOD EU-BO 012-01 Page 2 of 3 Copyright 2001, Ford Global Technologies, Inc. Procedure 1. According to the requirements of the different tests, cut specimens of prescribed dimensions from the material under test. If
7、the same specimen cannot be used for both tests, i.e. before and after humidity ageing, the required number of specimens of identical type must be provided. 2. Unless otherwise specified, condition specimens for 24 h at 23 +/- 2 C and a relative humidity of 50 +/- 5 %, prior to determination of orig
8、inal properties (values before ageing). 3. Check the specimen values before ageing (C) according to the requirements of the relevant material specification. 4. Add demineralised water to the autoclave but keep water level below the screen and set for the required temperature. Method A 105 +/- 3 C Me
9、thod B 120 +/- 3 C 5. When water is boiling place specimens on the screen without touching each other or any metal except the screen. 6. Shut autoclave but leave the pressure regulating valve open to drive out entrapped air. The valve is closed 2 minutes after the appearance of steam and the time of
10、 the test is started at this point. 7. The exposure time in the autoclave is as follows: Method A 3 hours Method B 5 hours 8. After the specified period turn off the heat, release the steam pressure, immediately remove the test specimens and dry for 16 hours in the oven at 70 +/- 1 C. Condition test
11、 specimens at 23 +/- 2 C and a relative humidity of 50 +/-5 %, if not otherwise specified for minimum 2 hours and maximum 24 hours, and test the specimens according to the relevant material specification. FORD LABORATORY TEST METHOD EU-BO 012-01 Page 3 of 3 Copyright 2001, Ford Global Technologies,
12、Inc. Evaluation Report and calculate the change of the material properties as follows: Change of material properties in % = C - D x 100 C C = Value before ageing D = Value after ageing When C and D are determined on the same test specimen the result C - D x 100 C should be calculated for each replic
13、ate test and the average of these results marked out for the sample. When, due to the nature of the test property C and D are determined on different test specimens the separate averages of the replicate measurements of C and of D are calculated and used in obtaining the result of C - D x 100. C 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.
