1、GM DAEWOO Auto & Technology EDS Engineering, GM DAEWOO Auto & Technology Standards THE TEST METHOD FOR TEAR STRENGTH OF ELASTOMERS EDS-T-7521 ISSUED DATE: 1996. 03. 27 REVISED DATE: 2006. 06. 19 VERSION: 3 EDS-T-7521THE TEST METHOD FOR TEAR STRENGTH OF ELASTOMERS PAGE: 1/3 ISSUED DATE: 1996. 03. 27
2、REVISED DATE: 2006. 06. 19 VERSION: 3 GM DAEWOO Auto & Technology 1. PURPOSE This standard covers the determination of the tear strength of elastomer tested at GMDAT. 2. APPLICATION This standard applies to measure tear strength for vulcanized rubber or PP/EPDM blend with highly filled EPDM rubber a
3、nd is unreasonable for rigid rubber. 3. DEFINITION 3.1. Tear strength: A measure of the energy required to propagate a tear in a flexible material such as a thin plastic film or elastomer. The tear strength is usually expressed as the ratio of the maximum load to the thickness of the specimen. 4. TE
4、ST SPECIMEN 4.1. The test specimen shall conform in shape as Fig. 1. 4.2. The thickness of specimen shall be measured in three places across the width of the specimen, near its center, and taken average value. 4.3. The thickness of the specimen should not fall outside the limits of 1.3 to 3.2mm. 4.4
5、 Five specimens per sample shall be tested for tear strength and two values which have large deviation for tear strength is rejected and taken average value of three values. 5. TEST CONDITION If there is no specified in the drawing, the specimen shall be maintained at 232, (205)% of the relative hu
6、midity at least 48 hours, prior to testing. 6. APPARATUS 6.1. Tensile strength measuring equipment It shall be maintained the test speed 50050mm/min and have a load/elongation recorder. 6.2. Thickness measuring device 6.3. Cutters or shears for taking test pieces. 7. PROCEDURE EDS-T-7521THE TEST MET
7、HOD FOR TEAR STRENGTH OF ELASTOMERS PAGE: 2/3 ISSUED DATE: 1996. 03. 27 REVISED DATE: 2006. 06. 19 VERSION: 3 GM DAEWOO Auto & Technology 7.1. Prior to test, measure a three parts thickness of test piece and calculate the arithmetic mean. 7.2. Test piece are placed to the grip in drive to moving a g
8、rip of the elongation tester. 7.3. Test speed are 5005mm/min, record the max. force when tears the test piece. 8. CALCULATION 8.1. Calculation of tear strength DFTs =Ts: Tear strength,(kN/m or lbf/in) F : Force(N or lbf) D : Specimen thickness(mm or in) 9. CORDING SYSTEM On drawings, material specif
9、ications etc., the requirement for the tear strength shall be indicated as follows. Tear Strength to EDS-T-7521 30 KN/m Requirements Test Method Designation 10. REFERENCE GME 60 283 PT3 Determination of tear propagation strength KS M 6783 Test method a tear strength of the vulcanized rubber ISO 34 R
10、ubber, vulcanized-determination of tear strength ISO 6133 Rubber and plastics-analysis of multi-peak traces obtained in determinations of tear strength and adhesion strength EDS-T-7521THE TEST METHOD FOR TEAR STRENGTH OF ELASTOMERS PAGE: 3/3 ISSUED DATE: 1996. 03. 27 REVISED DATE: 2006. 06. 19 VERSION: 3 GM DAEWOO Auto & Technology mm in. Dimensions Tolerances Dimensions Tolerances A 102 0.5 4.0 0.02 B 19 0.05 0.75 0.002 C 19 0.05 0.75 0.002 D 12.7 0.05 0.5 0.002 E 25 0.05 1.0 0.002 F 27 0.05 1.061 0.002 G 28 0.05 1.118 0.002 H 51 0.25 2.0 0.01 Fig. 1 Dies for tear test specimens
