Significance and Use
5.1 This test method may be used for routine inspection purposes by subjecting a required number of specimens to the test conditions for a specified time and noting the number that fail. The cracking obtained with the test reagent is indicative of what may be expected from a wide variety of surface-active agents, soaps, and organic substances that are not absorbed appreciably by the polymer.
5.2 Environmental stress-cracking is a property that is highly dependent upon the nature and level of the stresses applied and on the thermal history of the specimen (1). Under the conditions of the test method, high local multiaxial stresses are developed through the introduction of a controlled imperfection (2, 3). Environmental stress-cracking has been found to occur most readily under such conditions.
| Condition | Specimen Thickness | Notch Depth | Bath Temperature, °C | |||
| mmA | in. | mmA | in. | |||
| AB | min | 3.00 | 0.120 | 0.50 | 0.020 | 50 |
|
| max | 3.30 | 0.130 | 0.65 | 0.025 |
|
| BB | min | 1.84 | 0.0725 | 0.30 | 0.012 | 50 |
|
| max | 1.97 | 0.0775 | 0.40 | 0.015 |
|
| CC | min | 1.84 | 0.0725 | 0.30 | 0.012 | 100C |
|
| max | 1.97 | 0.0775 | 0.40 | 0.015 |
|
5.3 Information from this test method is not intended to be used for direct application to engineering problems.
As thermal history is recognized as an important variable, test results by this test method employing laboratory molded samples cannot necessarily be expected to show agreement with test results from samples obtained by other means. The true performance potential of a given ethylene plastic may, however, best be determined with specimens obtained from commercially prepared items (5).
Scope
1.1 This test method covers the determination of the susceptibility of ethylene plastics, as defined in Terminology D883, to environmental stress-cracking when subjected to the conditions herein specified. Under certain conditions of stress and in the presence of environments such as soaps, wetting agents, oils, or detergents, ethylene plastics may exhibit mechanical failure by cracking.
