ISO 37:1994 pdf download – Rubber, vulcanized or thermoplastic – Determination of tensile stress-strain properties
1 Scope
This International Standard describes a method for the determination of the tensile stress-strain properties of vulcanized and thermoplastic rubbers. The proper- ties which may be determined are the tensile strength, the elongation at break, the stress at a given strain and the elongation at a given stress. Means of specifying or determining the yield point are also given.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publi- cation, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most re- cent editions of the standards indicated below. Members of IEC and IS0 maintain registers of cur- rently valid International Standards.
ISO 471: -l), Rubber – Times, temperatures and hu- midities for conditioning and testing.
ISO 1826: 1981, Rubber, vulcanized – Time-in ten/al between vulcanization and testing – Specification.
ISO 3383: 1985, Rubber – General directions for achieving elevated or subnormal temperatures for test purposes.
ISO 4648: 1991, Rubber, vulcanized or thermoplastic – Determination of dimensions of test pieces and products for test purposes. IS0 4661-l : 1993, Rubber, vulcanized or thermoplastic – Preparation of samples and test pieces – Part 1: Physical tests.
ISO 5893:1993, Rubber and plastics test equipment – Tensile, flexural and compression types (constant rate of traverse) – Description.
7.4.1 The tensile-testing machine shall comply with the requirements of IS0 5893:1993, having an accu- racy of force measurement complying with grade B and, where used, an extensometer accuracy comply- ing with grade Dl for type 1 and 2 dumb-bell and type A ring test pieces, and grade El for type 3 and 4 dumb-bell and type B ring test pieces. The machine shall as a minimum be capable of operating at a rate of traverse of 100 mm/min, 200 mm/min and 500 mm/min and should preferably be equipped with facilities for the autographic recording of stress and strain.
7.4.2 For tests at temperatures other than standard temperature, a suitable thermostated chamber shall be fitted to the tensile-testing machine. Guidance for achieving elevated or subnormal temperatures is given in ISO 3383.
10.4 Conditioning of test pieces
Condition all test pieces in accordance with IS0 471. If the preparation of test pieces involves buffing, the interval between buffing and testing shall be not less than 16 h and not greater than 72 h. For tests at standard temperature, test pieces that do not require further preparation may be tested im- mediately, if cut from conditioned test samples. Where additional preparation is involved, a minimum conditioning period of 3 h at standard temperature shall be allowed. For tests at temperatures other than standard tem- perature, condition the test pieces at the temperature at which the test is to be conducted for a period suf- ficient to enable test pieces to attain substantial equilibrium in accordance with IS0 3383 (see 7.4.2).