Test methods for density and relative density of fiber reinforced plastics
1 Scope
This standard specifies the equipment, specimens, test steps, calculations, test results and test reports for determining the density and relative density of fiber reinforced plastics by buoyancy method and geometric method.
This standard is applicable to the determination of density and relative density of plate-shaped, rod-shaped, tubular and molded specimens of fiber reinforced plastics. It includes buoyancy method and geometry method. Buoyancy method is suitable for materials with weak hygroscopicity, while geometric method is suitable for materials with strong hygroscopicity. It can be selected according to the characteristics of materials and the agreement of the parties concerned.
Note: Materials with weak hygroscopicity refer to those that do not affect buoyancy measurement precision due to hygroscopicity.
This standard does not apply to materials with density less than 1,000 kg/m3.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated reference, subsequent amendments to (excluding any corrigendum), or revisions of, any of these publications do not apply. However, parties to agreements based on this standard are encouraged to investigate the possibility of applying the latest editions of the standards indicated below. For undated references, the latest edition applies.
GB 1446-2005 Fiber-reinforced plastics composites - The generals for determination of properties
3 Terms and definitions
For the purpose of this standard, the following terms and definitions apply.
3.1
density
mass of material per unit volume at t℃
3.2
relative density
ratio of the mass of a certain volume of material to that of reference substance of the same volume at the same temperature
or ratio of the density of a substance to that of a reference substance
4 Principle
4.1 Buoyancy method
According to Archimedes principle, the specimen volume is calculated by buoyancy. The mass of the specimen in the air divided by its volume is the density of the specimen material.
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Equipment
6 Materials
7 Specimen
8 Test steps
9 Calculation
10 Test result
11 Test report
