ASTM C1869-18
Standard Test Method for Open-Hole Tensile Strength of Fiber-Reinforced Advanced Ceramic Composites

Standard No.

ASTM C1869-18

Release Date

2018

Published By

American Society for Testing and Materials (ASTM)

Status

Be replaced

Replace By

ASTM C1869-18(2023)

Latest

ASTM C1869-18(2023)

Scope

1.1 This test method determines the open-hole (notched) tensile strength of continuous fiber-reinforced ceramic matrix composite (CMC) test specimens with a single through-hole of defined diameter (either 6 mm or 3 mm). The open-hole tensile (OHT) test method determines the effect of the single throughhole on the tensile strength and stress response of continuous fiber-reinforced CMCs at ambient temperature. The OHT strength can be compared to the tensile strength of an unnotched test specimen to determine the effect of the defined open hole on the tensile strength and the notch sensitivity of the CMC material. If a material is notch sensitive, then the OHT strength of a material varies with the size of the through-hole. Commonly, larger holes introduce larger stress concentrations and reduce the OHT strength. 1.2 This test method defines two baseline OHT test specimen geometries and a test procedure, based on Test Methods C1275 and D5766/D5766M. A flat, straight-sided ceramic composite test specimen with a defined laminate fiber architecture contains a single through-hole (either 6 mm or 3 mm in diameter), centered by length and width in the defined gage section (Fig. 1). A uniaxial, monotonic tensile test is performed along the defined test reinforcement axis at ambient temperature, measuring the applied force versus time/ displacement in accordance with Test Method C1275. Measurement of the gage length extension/strain is optional, using extensometer/displacement transducers. Bonded strain gages are optional for measuring localized strains and assessing bending strains in the gage section. 1.3 The open-hole tensile strength (SOHTx) for the defined hole diameter x (mm) is the calculated ultimate tensile strength based on the maximum applied force and the gross crosssectional area, disregarding the presence of the hole, per common aerospace practice (see 4.4). The net section tensile strength (SNSx) is also calculated as a second strength property, accounting for the effect of the hole on the cross-sectional area of the test specimen. 1.4 This test method applies primarily to ceramic matrix composites with continuous fiber reinforcement in multiple directions. The CMC material is typically a fiber-reinforced, 2D, laminated composite in which the laminate is balanced and symmetric with respect to the test direction. Composites with other types of reinforcement (1D, 3D, braided, unbalanced) may be tested with this method, with consideration of how the different architectures may affect the notch effect of the hole on the OHT strength and the tensile stress-strain response. This test method does not directly address discontinuous fiberreinforced, whisker-reinforced, or particulate-reinforced ceramics, although the test methods detailed here may be equally applicable to these composites. 1.5 This test method may be used for a wide range of CMC materials with different reinforcement fibers and ceramic matrices (oxide-oxide composites, silicon carbide (SiC) fibers in SiC matrices, carbon fibers in SiC matrices, and carboncarbon composites) and CMCs with different reinforcement architectures. It is also applicable to CMCs with a wide range of porosities and densities. 1.6 Annex A1 and Appendix X1 address how test specimens with different geometries and hole diameters may be prepared and tested to determine how those changes will modify the OHT strength properties, determine the notch sensitivity, and affect the stress-strain response. 1.7 The test method may be adapted for elevated temperature OHT testing by modifying the test equipment, specimens, and procedures per Test Method C1359 and as described in Appendix X2. The test method may also be adapted for environmental testing (controlled atmosphere/humidity at moderate (<300 °C) temperatures) of the OHT properties by the use of an environmental test chamber, per 7.6. 1.8 Values expressed in this test method are in accordance with the International System of Units (SI) and IEEE/ASTM SI 10. 1.9 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1 This test method is under the jurisdiction of ASTM Committee C28 on Advanced Ceramics and is the direct responsibility of Subcommittee C28.07 on Ceramic Matrix Composites. Current edition approved May 1, 2018. Published June 2018. Originally approved in 2018. DOI: 10.1520/C1869-18. Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. 1 1.10 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ASTM C1869-18 Referenced Document

• ASTM C1145 Standard Terminology of Advanced Ceramics
• ASTM C1239 Standard Practice for Reporting Uniaxial Strength Data and Estimating Weibull Distribution Parameters for Advanced Ceramics*， 2018-07-01 Update
• ASTM C1275 Standard Test Method for Monotonic Tensile Behavior of Continuous Fiber-Reinforced Advanced Ceramics with Solid Rectangular Cross-Section Test Specimens at Ambient Temperature*， 2024-04-20 Update
• ASTM C1326 Standard Test Method for Knoop Indentation Hardness of Advanced Ceramics
• ASTM C1327 Standard Test Method for Vickers Indentation Hardness of Advanced Ceramics
• ASTM C1359 Standard Test Method for Monotonic Tensile Strength Testing of Continuous Fiber-Reinforced Advanced Ceramics With Solid Rectangular Cross-Section Specimens at Elevated Temperatures
• ASTM C1465 Standard Test Method for Determination of Slow Crack Growth Parameters of Advanced Ceramics by Constant Stress-Rate Flexural Testing at Elevated Temperatures*， 2019-07-01 Update
• ASTM C1773 Standard Test Method for Monotonic Axial Tensile Behavior of Continuous Fiber-Reinforced Advanced Ceramic Tubular Test Specimens at Ambient Temperature*， 2021-07-01 Update
• ASTM C1793 Standard Guide for Development of Specifications for Fiber Reinforced Silicon Carbide-Silicon Carbide Composite Structures for Nuclear Applications*， 2024-01-01 Update
• ASTM C373 Standard Test Method for Water Absorption, Bulk Density, Apparent Porosity, and Apparent Specific Gravity of Fired Whiteware Products
• ASTM D3039/D3039M Standard Test Method for Tensile Properties of Polymer Matrix Composite Materials
• ASTM D3878 Standard Terminology Composite Materials
• ASTM D5766/D5766M Standard Test Method for Open Hole Tensile Strength of Polymer Matrix Composite Laminates
• ASTM D6856/D6856M Standard Guide for Testing Fabric-Reinforced “Textile” Composite Materials*， 2023-11-01 Update
• ASTM E1012 Standard Practice for Verification of Specimen Alignment Under Tensile Loading
• ASTM E105 Standard Practice for Probability Sampling Of Materials*， 2024-04-20 Update
• ASTM E122 Standard Practice for Calculating Sample Size to Estimate, With a Specified Tolerable Error, the Average for Characteristic of a Lot or Process
• ASTM E1402 Standard Terminology Relating to Sampling
• ASTM E2208 Standard Guide for Evaluating Non-Contacting Optical Strain Measurement Systems
• ASTM E251 Standard Test Methods for Performance Characteristics of Metallic Bonded Resistance Strain Gages
• ASTM E337 Standard Test Method for Measuring Humidity with a Psychrometer (the Measurement of Wet- and Dry-Bulb Temperatures)
• ASTM E4 Standard Practices for Force Verification of Testing Machines
• ASTM E6 Standard Terminology Relating to Methods of Mechanical Testing
• ASTM E691 Standard Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
• ASTM E83 Standard Practice for Verification and Classification of Extensometer
• IEEE/ASTM SI 10 American National Standard for Metric Practice

ASTM C1869-18 history

• 2023 ASTM C1869-18(2023) Standard Test Method for Open-Hole Tensile Strength of Fiber-Reinforced Advanced Ceramic Composites
• 2018 ASTM C1869-18 Standard Test Method for Open-Hole Tensile Strength of Fiber-Reinforced Advanced Ceramic Composites