この規格は、環境ストレス耐性を決定する方法を提供します。 (ESC) of plastics in the presence of chemical media under constant tensile force. It is suitable for molding and machining samples. It is used to evaluate the ESC of plastics exposed in different environments, determine the ESC of different plastics under specific environmental conditions, and evaluate the influence of molding conditions on the performance of products. The relationship between the measurement results of the sample short boat and the actual performance of the product cannot be evaluated by sub-evaluation.
1 適用範囲
この規格は、環境ストレス耐性を決定する方法を提供します。 (ESC) of plastics in the presence of chemical media under constant tensile force. It is suitable for molding and machining samples. It is used to evaluate the ESC of plastics exposed in different environments, determine the ESC of different plastics under specific environmental conditions, and evaluate the influence of molding conditions on the performance of products. The relationship between the measurement results of the sample short boat and the actual performance of the product cannot be evaluated by sub-evaluation.

ISO 6252-1992 “環境応力亀裂に対するプラスチックの耐性の測定 (ESC) – 定引張応力法”

2 原則
The specimen is subjected to a constant tensile force below the yield stress and immersed in a condition at a selected temperature. The time or stress of the specimen when breaking is recorded and the stress-cracking of the specimen is measured by one of the following methods:

方法A: To determine the new tensile stress caused at 100h, which can be obtained by interpolating the tensile stress with the American series diagram at the time of fracture.

方法B: determination of breaking time under specified tensile stress.

Method c: Measure the tensile stress against the new time curve until the specified time.

3 楽器

ISO 6252-1992 “環境応力亀裂に対するプラスチックの耐性の測定 (ESC) – 定引張応力法”

3.1 Test device, which can make the sample bear tensile stress and chemical environment at the same time. See Figure l and Figure 2 for details.

3.2 Thermostatic control bath or chamber can keep the test system at (23±1)℃ or higher test temperature, up to (100±0.5)℃.

3.3 Automatic timer, used to measure the sample failure time.

3.4 Suitable sample preparation equipment.

4 Chemical environment
The chemical environment used in the test is generally specified by the standards related to materials. If not specified, the following chemicals can be used in the application of materials:

a.95%(volume fraction) エタノール, pharmaceutical grade;

b.1% aqueous solution of nonylphenoxyl polyoxyethylene oxide monoethanol;

C. Refined linseed oil.

ISO 6252-1992 “環境応力亀裂に対するプラスチックの耐性の測定 (ESC) – 定引張応力法”

5 Test conditions
5.1 test temperature, 23 土壌 (1) ℃, priority (55 + / – 0.5) ℃, also can choose (40 + / – 0.5) ℃ and (70 + / – 0.5) ℃ and (85 + / – 0.5) ℃ and (100 + / – 0.5) ℃.

5.2 The test stress should be less than the maximum allowable stress of the material at the test temperature, あれは, the stress that produces 2% elongation after 1h. The test temperatures and applied stresses used for different materials are shown in Table 1.

6 Operation steps

ISO 6252-1992 “環境応力亀裂に対するプラスチックの耐性の測定 (ESC) – 定引張応力法”

7 結果の表現
7.1A method, calculate the arithmetic mean of the measured failure time. The logarithmic value of time was plotted against the tensile stress, and the same stress corresponding to 100h failure was determined by interpolation method.

7.2B method, calculate the arithmetic mean of the failure time obtained from the five samples.

7.3C method, calculate the arithmetic mean of the failure time of each stress used, and plot the tensile stress with the logarithm of the failure time.

Standard RESUME and bid acquisition status
This standard was formulated by IS0/TC6l/SC6 in 1981 and revised for the first time in l992. Now it is the second edition, cancelled and replaced by the first edition (IS06252; 1991), the technical content is consistent with IS06252,1981.

わが国には対応する規格がない.