Methods for Reinforced Plastics

Sims et al. [197] have pointed out that a redraft of ISO 527 tensile testing for plastics has resulted in two complementary parts for composites Part 4 based on ISO 3268 [199] covers isotropic and orthotropic materials, and Part 5 covers unidirectional materials. There is a need to harmonize these two methods into a new Part 5. Inputs were included from ISO, ASTM, CRAG, and EN aerospace methods. The remaining three parts are Part 1—general principles. Part 2—plastics and molding materials (including short fiber-reinforced materials), and Part 3—films. ISO DIS 527-5 has in parallel been voted as a CEN standard (EN 527-5) and should, with Part 4, replace EN61 [212] and possibly two aerospace EN standards [34,42,132,160,163-165,199-213]. 

Obtaining agreement between ISO, CEN general series, EN aerospace-carbon only, ASTM, and JIS in specimen sizes for unidirectional reinforced materials was a notable first step toward harmonization of the test methods, particularly because the 1.25-cm-wide ASTM specimen [215] has been in extensive use for many years. The agreed dimensions are 15 x 1 mm for 0° and 25 x 2 mm for 90° fiber direction specimens. After agreement on the specimen sizes (which is the same in all standards 

A complete list of recommended mechanical test methods for fiber-reinforced plastics has been reported [216-245], 

The main forums for standardization in the UK were for many years either through BSI itself or via its role in support of ISO standards. For the materials testing and specification level, the work within ISO is undertaken in Technical Committee (TC) 61 (Plastics) mainly within Subcommittee SC13 (Composites and Reinforcement Fibers). In addition to this, many other subcommittees, such as SC2 for dealing with mechanical test methods, SC4 for fire tests, and SC12 for thermosets, develop relevant test methods covering both unreinforced and reinforced plastics. 

The subcommittees forming SC13 are shown in Table 3.14. It should be noted that the work program on test methods for laminates is undertaken in Working Groups (WGs) 14 and 16. 

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