ISO 19587:2021 pdf download – Fine ceramics (advanced ceramics, advanced technical ceramics) — Mechanical properties of ceramic composites at elevated temperature in air atmospheric pressure — Determination of in-plane shear strength.
1 Scope This document specifies a method for the determination of in-plane shear strength of continuous fibre-reinforced ceramic composites at elevated temperature in air or inert atmosphere by the asymmetric four-point bending test on double-edge notched specimens. The shear strength in plane (1,2) can be evaluated, where direction 1 is that of the greater fraction of reinforcement and direction 2 is perpendicular to direction 1. Methods for test piece fabrication, testing modes and rates (load or displacement rate), data collection and reporting procedures are addressed. This document applies to all ceramic matrix composites with continuous fibre-reinforcement: unidirectional (1D), bidirectional (2D) and tridirectional (xD, with 2 < x ≤ 3). This document is for material development, material comparison, quality assurance, characterization, reliability and design data generation. 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 3611, Geometrical product specifications (GPS) — Dimensional measuring equipment: Micrometers for external measurements — Design and metrological characteristics 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 ISO 19634, Fine ceramics (advanced ceramics, advanced technical ceramics) — Ceramic composites — Notations and symbols ISO 20507, Fine ceramics (advanced ceramics, advanced technical ceramics) — Vocabulary IEC 60584-1, Thermocouples — Part 1: Reference tables IEC 60584-2, Thermocouples — Part 2: Tolerances
4 Principle The in-plane shear strength of continuous fibre-reinforced ceramic composites, as determined by this document, is measured by the asymmetric four-point bending test at elevated temperature in air or inert atmosphere. According to this test, the shear strength is determined by loading a test coupon in the form of a rectangular flat strip with symmetric, centrally located V-notches using a mechanical testing machine and an asymmetric four-point bending fixture. Failure of the test piece occurs by shear force between the V-notches. Schematics of the test set-up and the test piece are shown in Figures 1 and 2, respectively. The free body, bending moment and shear force diagrams by the asymmetric four-point bending flexure are illustrated in Figure 3.