1、GM DAEWOO Auto & Technology EDS Engineering, GM DAEWOO Auto & Technology Standards TEST FOR DEFLECTION TEMPERATURE OF PLASTICS UNDER LOAD EDS-T-7520 ISSUED DATE: 1995. 09. 25 REVISED DATE: 2006. 08. 31 VERSION: 4 EDS-T-7520TEST FOR DEFLECTION TEMPERATURE OF PLASTICS UNDER LOAD PAGE: 1/3 ISSUED DATE:
2、 1995. 09. 25 REVISED DATE: 2006. 08. 31 VERSION: 4 GM DAEWOO Auto & Technology 1. PURPOSE This standard is used to determine the deflection characteristics of plastic raw material testing piece under increasing temperature and specific load that generates specific bending stress. Note) The resultin
3、g value under the standard does not mean the maximum usable temperature for the material. 2. DEFINITION 2.1. Heat deflection temperature: It means the temperature at which plastic raw material testing piece is deformed to specific length under specific weight. 3. DIMENSIONS AND NUMBER OF TEST PIECES
4、 3.1. It shall be minimum (1100.2)mm in length, 6.20.2mm in width, 12.412.7mm in height, and its surfaces shall be smooth flat. 3.2. Unless otherwise specified, 3 test samples shall be tested and report the measured values 4. CONDITIONING Test piece before testing shall be under conditions, +232K an
5、d (505)% of relative humidity for 40 hours or more. 5. TESTING EQUIPMENT 5.1. All components of testing equipment in Figure 1 are as follows. 5.1.1. Supports for test piece Space between supports shall be (1002)mm, diameter in the connection of supports and push metal shall be (30.2)mm and a coeffic
6、ient of line expansion in all parts shall be the same. 5.1.2. Heating bath Heat-transfer medium such as mineral oil, liquid paraffin, and silicon oil not affecting testing shall be used, and increasing rate of (20.2)/minute shall be kept. 5.1.3. Temperature-measuring device Temperature from -5 to 30
7、0 shall be possibly measured in error within 0.5K. 5.1.4. Deflection measurement device Appliance to measure deflection quantity of testing piece shall be possibly measured to 0.01mm. When testing piece reaches the specified deflection, heating stops automatically and alarm bell rings. 5.1.5. Force
8、The force which is applied to test pieces is 4.6kg(66psi) or 18.6kg(264psi) using the weight, the force by materials EDS-T-7520TEST FOR DEFLECTION TEMPERATURE OF PLASTICS UNDER LOAD PAGE: 2/3 ISSUED DATE: 1995. 09. 25 REVISED DATE: 2006. 08. 31 VERSION: 4 GM DAEWOO Auto & Technology is selected acco
9、rding to specification that is indicated on material standard Figure 1. 5.2. Pincet 6. TESTING METHOD 6.1. Select the testing weight of drawing or material standard. 6.2. Check the identical with the measured dimension of the test piece and the specification. 6.3. Put testing piece on the supporting
10、 table of testing appliance within 10mm not to be touched by thermometer. 6.4. Keep testing piece loaded for 5 minutes before heating and adjust the deflection quantity at zero. 6.5. Raise the temperature of heated tub by the rate of (20.2)/minute and test. 6.6. When the testing piece is deflected b
11、y 0.26mm, stop the testing and write the temperature down. 7. EXPRESSION OF RESULT Measured heat deflection temperature shall be marked up to 1, and the testing values shall be expressed by EDS-T-7520TEST FOR DEFLECTION TEMPERATURE OF PLASTICS UNDER LOAD PAGE: 3/3 ISSUED DATE: 1995. 09. 25 REVISED D
12、ATE: 2006. 08. 31 VERSION: 4 GM DAEWOO Auto & Technology 8. CODE SYSTEM Heat deflection temperature on drawing or material standard is as follows: Heat deflection temperature - EDS-T-7520 - 120 or more Requirements Test method Test designation 9. REFERENCE ASTM D 648, “Standard test method for deflection temperature of plastics under flexural load”
