BS ISO 1922:2018 pdf download

BS ISO 1922:2018 pdf download.Rigid cellular plastics — Determination of shear properties
1 Scope
This document specifies a procedure of determining the shear strength of rigid cellular plastics. It also provides for the determination of shear modulus and shear strain.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 1923, Cellular plastics and rubbers — Determination of linear dimensions
ISO 7500-1, Metallic materials — Calibration and verification of static uniaxial testing machines — Part 1:Tension/compression testing machines — Calibration and verification of the force-measuring system
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at http://www.electropedia.org/
4 Principle
A shear stress is applied to a test specimen of defined shape by means of rigid specimen supports bonded to the specimen.
There are two procedures:
— Procedure A, which is recommended for shear strength measurement only;
— Procedure B, which uses an extensometer or similar device to measure displacement and is, thus,
the recommended method to calculate the shear modulus and strain (and strength as well).
5 Apparatus
5.1 Test machine
5.1.1 General
A test machine capable of applying a sufficient force within the maximum displacement experienced in the shear test.
It shall be capable of operating at a constant rate of movement of the movable head of (1 ± 0,5) mm/min in a direction parallel to the longitudinal axis of the test specimen assembly.
5.1.2 Single test specimen arrangement
The test machine shall exert longitudinal shear forces through parallel plates bonded to a single test specimen of dimensions as in 6.2. The parallel plates shall be rigid with one plate attached to the fixed parts and the other to the movable parts of the test machine.
5.1.3 Double test specimen arrangement
The test machine shall exert longitudinal shear forces through parallel plates bonded to a double test specimen of dimensions as in 6.3. The parallel plates shall be rigid with the outer plates attached to the fixed parts and the central plate to the movable parts of the test machine.
5.2 Specimen supports
5.2.1 Single test specimen assembly
Two flat rigid specimen supports with a length 330 mm, a width of 50 mm and a thickness of (16 ± 1) mm shall be attached to the grips of the test machine via an adaptor and universal joint. The procedure of attaching the specimen supports to the grips is shown in Figure 1. The thickness of the adaptors that connect the specimen supports to the test machine grips shall be the same as the thickness of the test specimen. NOTE Flat, rectangular-sectioned mild steel plates with a thickness of 16 mm have proved to be suitable for the support material.