Rubber, vulcanized or thermoplastic Determination of hardness (hardness between 10 IRHD and 100 IRHD)
Warning: Persons using this standard shall be familiar with normal laboratory practice. This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health measures and to ensure compliance with any national regulatory conditions.
Note: Some operations covered by this standard may use or generate some substances or wastes with a polluting impact on the local environment. Appropriate documentation for the disposal of these substances after use shall be developed.
1. Scope
This standard specifies four methods for the determination of the hardness of vulcanized or thermoplastic rubbers on flat surfaces (standard-hardness methods) and four methods for the determination of the apparent hardness of curved surfaces (apparent-hardness methods). The hardness is expressed in international rubber hardness degrees (IRHD). The methods cover the hardness range from 10 IRHD to 100 IRHD.
These methods differ primarily in the diameter of the indenting ball and the magnitude of the indenting force, these being chosen to suit the particular application. The range of applicability of each method is indicated in Figure 1.
This International Standard does not specify a method for the determination of hardness by a pocket hardness meter, which is described in ISO 7619-2.
Key:
X——hardness (IRHD);
a——Method L and Method CL;
b——Methods N, M and Methods CN, CM;
c——Method H and Method CH.
Figure 1 Scope of application of various methods
This International Standard specifies the following four methods for the determination of standard hardness.
Method N (normal test) is appropriate for rubbers with a hardness in the range 35 IRHD to 85 IRHD, but can also be used for hardnesses in the range 30 IRHD to 95 IRHD.
Method H (high-hardness test) is appropriate for rubbers with a hardness in the range 85 IRHD to 100 IRHD.
Method L (low-hardness test) is appropriate for rubbers with a hardness in the range 10 IRHD to 35 IRHD.
Foreword i
Introduction ii
1. Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Apparatus
6 Test pieces
7 Time interval between vulcanization and testing
8 Conditioning of test pieces
9 Temperature of test
10 Procedure
11 Number of readings
12 Expression of results
13 Precision
14 Test report
Annex A (Informative) Empirical relationship between indentation depth and hardness
Annex B (Informative) Precision results from interlaboratory test programs (ITPs)
Annex C (Informative) Guidance for using precision results
Bibliography
Rubber, vulcanized or thermoplastic Determination of hardness (hardness between 10 IRHD and 100 IRHD)
Warning: Persons using this standard shall be familiar with normal laboratory practice. This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health measures and to ensure compliance with any national regulatory conditions.
Note: Some operations covered by this standard may use or generate some substances or wastes with a polluting impact on the local environment. Appropriate documentation for the disposal of these substances after use shall be developed.
1. Scope
This standard specifies four methods for the determination of the hardness of vulcanized or thermoplastic rubbers on flat surfaces (standard-hardness methods) and four methods for the determination of the apparent hardness of curved surfaces (apparent-hardness methods). The hardness is expressed in international rubber hardness degrees (IRHD). The methods cover the hardness range from 10 IRHD to 100 IRHD.
These methods differ primarily in the diameter of the indenting ball and the magnitude of the indenting force, these being chosen to suit the particular application. The range of applicability of each method is indicated in Figure 1.
This International Standard does not specify a method for the determination of hardness by a pocket hardness meter, which is described in ISO 7619-2.
Key:
X——hardness (IRHD);
a——Method L and Method CL;
b——Methods N, M and Methods CN, CM;
c——Method H and Method CH.
Figure 1 Scope of application of various methods
This International Standard specifies the following four methods for the determination of standard hardness.
Method N (normal test) is appropriate for rubbers with a hardness in the range 35 IRHD to 85 IRHD, but can also be used for hardnesses in the range 30 IRHD to 95 IRHD.
Method H (high-hardness test) is appropriate for rubbers with a hardness in the range 85 IRHD to 100 IRHD.
Method L (low-hardness test) is appropriate for rubbers with a hardness in the range 10 IRHD to 35 IRHD.
Contents of GB/T 6031-2017
Foreword i
Introduction ii
1. Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Apparatus
6 Test pieces
7 Time interval between vulcanization and testing
8 Conditioning of test pieces
9 Temperature of test
10 Procedure
11 Number of readings
12 Expression of results
13 Precision
14 Test report
Annex A (Informative) Empirical relationship between indentation depth and hardness
Annex B (Informative) Precision results from interlaboratory test programs (ITPs)
Annex C (Informative) Guidance for using precision results
Bibliography
