1.1 This standard specifies a method for determining the lowest temperature at which rubber materials do not exhibit brittle failure when impacted under specified conditions.
Brittleness temperatures thus determined with multiple test piece method do not necessarily relate to the lowest temperatures at which the material may be used, since brittleness temperature (multiple test piece method) will be modified by the conditions of contact and especially by the rate of impact. Data obtained by this method should therefore be used to predict the behavior of vulcanized rubber at low temperatures only in applications in which the conditions of deformation are similar to those specified in the test.
1.2 Two procedures are described: procedure A, in which the brittleness temperature is determined with multiple test piece method, and procedure B, in which the test piece is impacted at a specified temperature.
The latter procedure is used in the classification of vulcanized rubber and for specification purposes.
Note: A similar test for rubber-coated fabrics is described in GB/T 12584-90.
2 Normative references
GB 2941 Rubber - Standard temperatures, humidities and times for the conditioning environmental and testing of test pieces
GB 9865 Rubber, vulcanized - Preparation of samples and test pieces
GB/T 9868 Rubber - General directions for achieving elevated or subnormal temperatures for test purposes
GB/T 12584 Rubber or plastics coated fabrics - Low-temperature impact test
3 Definitions
For the purpose of this standard, the following definitions apply.
GB/T 15256-1994 The following standards are cited: