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ASTM C1421-10

(Test Method)

Standard Test Methods for Determination of Fracture Toughness of Advanced Ceramics at Ambient Temperature

Standard Test Methods for Determination of Fracture Toughness of Advanced Ceramics at Ambient Temperature

SIGNIFICANCE AND USE
Fracture toughness, KIc, is a measure of the resistance to crack extension in a brittle material. These test methods may be used for material development, material comparison, quality assessment, and characterization.
The pb and the vb fracture toughness values provide information on the fracture resistance of advanced ceramics containing large sharp cracks, while the sc fracture toughness value provides this information for small cracks comparable in size to natural fracture sources. Cracks of different sizes may be used for the sc method. If the fracture toughness values vary as a function of the crack size it can be expected that KIsc will differ from KIpb and KIvb.
SCOPE
1.1 These test methods cover the fracture toughness, KIc, determination of advanced ceramics at ambient temperature. The methods determine KIpb (precracked beam test specimen), KIsc (surface crack in flexure), and KIvb (chevron-notched beam test specimen). The fracture toughness values are determined using beam test specimens with a sharp crack. The crack is either a straight-through crack formed via bridge flexure (pb), or a semi-elliptical surface crack formed via Knoop indentation (sc), or it is formed and propagated in a chevron notch (vb), as shown in Fig. 1.
Note 1—The terms bend(ing) and flexure are synonymous in these test methods.
1.2 These test methods are applicable to materials with either flat or with rising R-curves. Differences in test procedure and analysis may cause the values from each test method to be different. For many materials, such as the silicon nitride Standard Reference Material 2100, the three methods give identical results at room temperature in ambient air.
1.3 The fracture toughness values for a material can be functions of environment, test rate and temperature. These test methods give fracture toughness values for specific conditions of environment, test rate and temperature.
1.4 These test methods are intended primarily for use with advanced ceramics which are macroscopically homogeneous. Certain whisker- or particle-reinforced ceramics may also meet the macroscopic behavior assumptions. Single crystals may also be tested.
1.5 This standard begins with a main body that provides information on fracture toughness testing in general. It is followed by annexes and appendices with specific information for the particular test methods.

General Information

Status
Historical
Publication Date
30-Nov-2010
ICS
81.060.30 - Advanced ceramics
Technical Committee
C28 - Advanced Ceramics
Drafting Committee
C28.01 - Mechanical Properties and Performance
Current Stage
Ref Project

Relations

Replaces
ASTM C1421-09 - Standard Test Methods for Determination of Fracture Toughness of Advanced Ceramics at Ambient Temperature
Effective Date
01-Dec-2010
Replaced By
ASTM C1421-15 - Standard Test Methods for Determination of Fracture Toughness of Advanced Ceramics at Ambient Temperature
Effective Date
01-Jul-2015
Referred By
ASTM F2094/F2094M-18a - Standard Specification for Silicon Nitride Bearing Balls
Effective Date
01-Dec-2010
Referred By
ASTM E2899-19e1 - Standard Test Method for Measurement of Initiation Toughness in Surface Cracks Under Tension and Bending
Effective Date
01-Dec-2010
Referred By
ASTM F2730/F2730M-18a - Standard Specification for Silicon Nitride Cylindrical Bearing Rollers
Effective Date
01-Dec-2010
Referred By
ASTM D7779-20 - Standard Test Method for Determination of Fracture Toughness of Graphite at Ambient Temperature
Effective Date
01-Dec-2010

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ASTM C1421-10 - Standard Test Methods for Determination of Fracture Toughness of Advanced Ceramics at Ambient TemperatureASTM C1421-10 - Standard Test Methods for Determination of Fracture Toughness of Advanced Ceramics at Ambient Temperature
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REDLINE ASTM C1421-10 - Standard Test Methods for Determination of Fracture Toughness of Advanced Ceramics at Ambient TemperatureREDLINE ASTM C1421-10 - Standard Test Methods for Determination of Fracture Toughness of Advanced Ceramics at Ambient Temperature
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REDLINE ASTM C1421-10 - Standard Test Methods for Determination of Fracture Toughness of Advanced Ceramics at Ambient Temperature
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Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: C1421 − 10
StandardTest Methods for
Determination of Fracture Toughness of Advanced Ceramics
1
at Ambient Temperature
This standard is issued under the fixed designation C1421; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 1.5 This standard begins with a main body that provides
information on fracture toughness testing in general. It is
1.1 These test methods cover the fracture toughness, K ,
Ic
followed by annexes and appendices with specific information
determination of advanced ceramics at ambient temperature.
for the particular test methods.
The methods determine K (precracked beam test specimen),
Ipb
Main Body Section
K (surfacecrackinflexure),and K (chevron-notchedbeam
Isc Ivb
Scope 1
test specimen). The fracture toughness values are determined
Referenced Documents 2
using beam test specimens with a sharp crack. The crack is
Terminology (including definitions, orientation and symbols) 3
Summary of Test Methods 4
either a straight-through crack formed via bridge flexure (pb),
Significance and Use 5
orasemi-ellipticalsurfacecrackformedviaKnoopindentation
Interferences 6
(sc), or it is formed and propagated in a chevron notch (vb), as
Apparatus 7
Test Specimen Configurations, Dimensions and Preparations 8
shown in Fig. 1.
General Procedures 9
Report (including reporting tables) 10
NOTE 1—The terms bend(ing) and flexure are synonymous in these test
Precision and Bias 11
methods.
Keywords 12
1.2 These test methods are applicable to materials with Summary of Changes
Annexes
eitherflatorwithrisingR-curves.Differencesintestprocedure
Test Fixture Geometries Annex A1
and analysis may cause the values from each test method to be
Procedures and Special Requirements for Precracked Beam Annex A2
Method
different. For many materials, such as the silicon nitride
Procedures and Special Requirements for Surface Crack in Annex A3
Standard Reference Material 2100, the three methods give
Flexure Method
identical results at room temperature in ambient air.
Procedures and Special Requirements for Chevron Notch Flexure Annex A4
Method
1.3 The fracture toughness values for a material can be
Appendices
functions of environment, test rate and temperature. These test
Precrack Characterization, Surface Crack in Flexure Method Appendix
X1
methods give fracture toughness values for specific conditions
Complications in Interpreting Surface Crack in Flexure Precracks Appendix
of environment, test rate and temperature.
X2
Alternative Precracking Procedure, Surface Crack in Flexure Appendix
1.4 These test methods are intended primarily for use with
Method X3
advanced ceramics which are macroscopically homogeneous.
Chamfer Correction Factors, Surface Crack in Flexure Method Only Appendix
X4
Certainwhisker-orparticle-reinforcedceramicsmayalsomeet
Crack Orientation Appendix
the macroscopic behavior assumptions. Single crystals may
X5
also be tested.
1.6 Valuesexpressedinthesetestmethodsareinaccordance
with the International System of Units (SI) and Practice
1 IEEE/ASTM SI10.
This test method is under the jurisdiction of ASTM Committee C28 on
Advanced Ceramics and is the direct responsibility of Subcommittee C28.01 .
1.7 The values stated in SI units are to be regarded as
Current edition approved Dec. 1, 2010. Published January 2011. Originally
standard. No other units of measurement are included in this
approved in 1999. Last previous edition approved in 2009 as C1421–09. DOI:
10.1520/C1421-10. standard.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
C1421 − 10
NOTE 1—The figures on the right show the test specimen cross sections and crack types. Four-point loading may be used with all three methods.
Three-point may be used with the pb and vb specimens.
FIG. 1 The Three Test Methods
1.8 This standard does not purport to address all of the 3.1.4 slow crack growth (SCG)—sub critical crack growth
safety concerns, if any, associated with its use. It is the (extension)whichmayresultfrom,butisnotrestrictedto,such
responsibility of the user of this standard to establish appro- mechanisms as environmentally-assisted stress corrosion or
priate safety and health practices and determine the applica- diffusive crack growth.
bility of regulatory limitations prior to use.
-3/2
3.1.5 stress-intensity factor, K [FL ]—the magnitude of
the ideal-crack-tip stress field (stress field singularity) for a
2. Referenced Documents
particular mode in a homogeneous, linear-elastic body.
2
2.1 ASTM Standards:
(E1823)
C116
...

This document is not anASTM standard and is intended only to provide the user of anASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation:C1421–09 Designation: C1421 – 10
Standard Test Methods for
Determination of Fracture Toughness of Advanced Ceramics
1
at Ambient Temperature
This standard is issued under the fixed designation C1421; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope *
1.1 These test methods cover the fracture toughness, K , determination of advanced ceramics at ambient temperature. The
Ic
methods determine K (precracked beam test specimen), K (surface crack in flexure), and K (chevron-notched beam test
Ipb Isc Ivb
specimen). The fracture toughness values are determined using beam test specimens with a sharp crack. The crack is either a
straight-through crack formed via bridge flexure (pb), or a semi-elliptical surface crack formed via Knoop indentation (sc), or it
is formed and propagated in a chevron notch (vb), as shown in Fig. 1.
NOTE 1—The terms bend(ing) and flexure are synonymous in these test methods.
1.2 These test methods are applicable to materials with either flat or with rising R-curves. Differences in test procedure and
analysis may cause the values from each test method to be different. For many materials, such as the silicon nitride Standard
Reference Material 2100, the three methods give identical results at room temperature in ambient air.
1.3 The fracture toughness values for a material can be functions of environment, test rate and temperature.These test methods
give fracture toughness values for specific conditions of environment, test rate and temperature.
1.4 Thesetestmethodsareintendedprimarilyforusewithadvancedceramicswhicharemacroscopicallyhomogeneous.Certain
whisker- or particle-reinforced ceramics may also meet the macroscopic behavior assumptions. Single crystals may also be tested.
1.5 This standard begins with a main body that provides information on fracture toughness testing in general. It is followed by
annexes and appendices with specific information for the particular test methods.
Main Body Section
Scope 1
Referenced Documents 2
Terminology (including definitions, orientation and symbols) 3
Summary of Test Methods 4
Significance and Use 5
Interferences 6
Apparatus 7
Test Specimen Configurations, Dimensions and Preparations 8
General Procedures 9
Report (including reporting tables) 10
Precision and Bias 11
Keywords 12
Summary of Changes
Annexes
Test Fixture Geometries A1
Procedures and Special Requirements for Precracked Beam A2
Method
Procedures and Special Requirements for Surface Crack in Flex- A3
ure Method
Procedures and Special Requirements for Chevron Notch Flexure A4
Method
Appendices
Precrack Characterization, Surface Crack in Flexure Method X1
Complications in Interpreting Surface Crack in Flexure Precracks X2
Alternative Precracking Procedure, Surface Crack in Flexure X3
Method
Chamfer Correction Factors, Surface Crack in Flexure Method Only X4
Crack Orientation X5
1
This test method is under the jurisdiction of ASTM Committee C28 on Advanced Ceramics and is the direct responsibility of Subcommittee C28.01 .
Current edition approved May 1, 2009. Published August 2009. Originally approved in 1999. Last previous edition approved in 2007 as C1421-01b (2007). DOI:
10.1520/C1421-09.
Current edition approved Dec. 1, 2010. Published January 2011. Originally approved in 1999. Last previous edition approved in 2009 as C1421–09. DOI:
10.1520/C1421-10.
*A Summary of Changes section appears at the end of this standard.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

---------------------- Page: 1 ----------------------
C1421 – 10
1.6 Values expressed in these test methods are in accordance with the International System of Units (SI) and Practice
IEEE/ASTM SI10.
1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.8 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 and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
C1161 Test Method for Flexural Strength of Advanced Ceramics at Ambient Temperature
C1322 Practice for Fractography and
...

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FIG. 2 Flexure Loading Configurations  
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SIGNIFICANCE AND USE
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1.1.3 Test Geometry IIB—A four-point loading system utilizing two force application points equally spaced from their adjacent support points, with a distance between force application points of one-third of the support span.  
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FIG. 1 Four-Point-1/4-Point Flexure Loading Configuration  
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5.1 For advanced ceramics, Knoop indenters are used to create indentations. The surface projection of the long diagonal is measured with optical microscopes.  
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1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.3 Units—When Knoop and Vickers hardness tests were developed, the force levels were specified in units of grams-force (gf) and kilograms-force (kgf). This standard specifies the units of force and length in the International System of Units (SI); that is, force in newtons (N) and length in mm or μm. However, because of the historical precedent and continued common usage, force values in gf and kgf units are occasionally provided for information. This test method specifies that Knoop hardness be reported either in units of GPa or as a dimensionless Knoop hardness number.  
1.4 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.  
1.5 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.

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ASTM
ASTM C1495-16(2023)(Test Method)
Standard Test Method for Effect of Surface Grinding on Flexure Strength of Advanced Ceramics

SIGNIFICANCE AND USE
5.1 Surface grinding can cause a significant decrease4 in the flexure strength of advanced ceramic materials. The magnitude of the loss in strength is determined by the grinding conditions and the response of the material. This test method can be used to obtain a detailed characterization of the relationship between grinding conditions and flexure strength for an advanced ceramic material. The effect on flexure strength of varying a single grinding parameter or several grinding parameters can be measured. The method may also be used to compare and rank different materials according to their response to one or more different grinding conditions. Results obtained by this method can be used to develop an optimum grinding process with respect to maximizing material removal rate for a specified flexure strength requirement. The test method can assist in the development of improved grinding-damage-tolerant ceramic materials. It may also be used for quality control purposes to monitor and assure the consistency of a grinding process in the fabrication of parts from advanced ceramic materials. The test method is applicable to grinding methods that generate a planar surface and is not directly applicable to grinding methods that produce non-planar surfaces such as cylindrical and centerless grinding.
SCOPE
1.1 This test method covers the determination of the effect of surface grinding on the flexure strength of advanced ceramics. Surface grinding of an advanced ceramic material can introduce microcracks and other changes in the near surface layer, generally referred to as damage (see Fig. 1 and Ref. (1)).2 Such damage can result in a change—most often a decrease—in flexure strength of the material. The degree of change in flexure strength is determined by both the grinding process and the response characteristics of the specific ceramic material. This method compares the flexure strength of an advanced ceramic material after application of a user-specified surface grinding process with the baseline flexure strength of the same material. The baseline flexure strength is obtained after application of a surface grinding process specified in this standard. The baseline flexure strength is expected to approximate closely the inherent strength of the material. The flexure strength is measured by means of ASTM flexure test methods.
FIG. 1 Microcracks Associated with Grinding (Ref. (1))2  
1.2 Flexure test methods used to determine the effect of surface grinding are C1161 Test Method for Flexure Strength of Advanced Ceramics at Ambient Temperatures and C1211 Test Method for Flexure Strength of Advanced Ceramics at Elevated Temperatures.  
1.3 Materials covered in this standard are those advanced ceramics that meet criteria specified in flexure testing standards C1161 and C1211.  
1.4 The flexure test methods supporting this standard (C1161 and C1211) require test specimens that have a rectangular cross section, flat surfaces, and that are fabricated with specific dimensions and tolerances. Only grinding processes that are capable of generating the specified flat surfaces, that is, planar grinding modes, are suitable for evaluation by this method. Among the applicable machine types are horizontal and vertical spindle reciprocating surface grinders, horizontal and vertical spindle rotary surface grinders, double disk grinders, and tool-and-cutter grinders. Incremental cross-feed, plunge, and creep-feed grinding methods may be used.  
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.6 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.  
1.7 This international standard was develop...

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ASTM
ASTM C1211-18(2023)(Test Method)
Standard Test Method for Flexural Strength of Advanced Ceramics at Elevated Temperatures

SIGNIFICANCE AND USE
4.1 This test method may be used for material development, quality control, characterization, and design data generation purposes. This test method is intended to be used with ceramics whose flexural strength is ∼50 MPa (∼7 ksi) or greater.  
4.2 The flexure stress is computed based on simple beam theory, with assumptions that the material is isotropic and homogeneous, the moduli of elasticity in tension and compression are identical, and the material is linearly elastic. The average grain size should be no greater than 1/50 of the beam thickness. The homogeneity and isotropy assumptions in the test method rule out the use of it for continuous fiber-reinforced composites for which Test Method C1341 is more appropriate.  
4.3 The flexural strength of a group of test specimens is influenced by several parameters associated with the test procedure. Such factors include the testing rate, test environment, specimen size, specimen preparation, and test fixtures. Specimen and fixture sizes were chosen to provide a balance between the practical configurations and resulting errors as discussed in Test Method C1161, and Refs (1-3).4 Specific fixture and specimen configurations were designated in order to permit the ready comparison of data without the need for Weibull size scaling.  
4.4 The flexural strength of a ceramic material is dependent on both its inherent resistance to fracture and the size and severity of flaws. Variations in these cause a natural scatter in test results for a sample of test specimens. Fractographic analysis of fracture surfaces, although beyond the scope of this test method, is highly recommended for all purposes, especially if the data will be used for design as discussed in Ref (4) and Practices C1322 and C1239.  
4.5 This method determines the flexural strength at elevated temperature and ambient environmental conditions at a nominal, moderately fast testing rate. The flexural strength under these conditions may or may not necessarily be the...
SCOPE
1.1 This test method covers determination of the flexural strength of advanced ceramics at elevated temperatures.2 Four-point-1/4-point and three-point loadings with prescribed spans are the standard as shown in Fig. 1. Rectangular specimens of prescribed cross-section are used with specified features in prescribed specimen-fixture combinations. Test specimens may be 3 by 4 by 45 to 50 mm in size that are tested on 40-mm outer span four-point or three-point fixtures. Alternatively, test specimens and fixture spans half or twice these sizes may be used. The test method permits testing of machined or as-fired test specimens. Several options for machining preparation are included: application matched machining, customary procedures, or a specified standard procedure. This test method describes the apparatus, specimen requirements, test procedure, calculations, and reporting requirements. The test method is applicable to monolithic or particulate- or whisker-reinforced ceramics. It may also be used for glasses. It is not applicable to continuous fiber-reinforced ceramic composites.  
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.  
1.3 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.  
1.4 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.

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ASTM
ASTM C1323-22(Test Method)
Standard Test Method for Ultimate Strength of Advanced Ceramics with Diametrally Compressed C-Ring Specimens at Ambient Temperature

SIGNIFICANCE AND USE
4.1 This test method may be used for material development, material comparison, quality assurance, and characterization. Extreme care should be exercised when generating design data.  
4.2 For a C-ring under diametral compression, the maximum tensile stress occurs at the outer surface. Hence, the C-ring specimen loaded in compression will predominately evaluate the strength distribution and flaw population(s) on the external surface of a tubular component in the hoop direction. Accordingly, the condition of the inner surface may be of lesser consequence in specimen preparation and testing.
Note 1: A C-ring in tension or an O-ring in compression may be used to evaluate the internal surface.  
4.2.1 The flexure stress is computed based on simple curved beam theory (1-5).3 It is assumed that the material is isotropic and homogeneous, the moduli of elasticity are identical in compression or tension, and the material is linearly elastic. These homogeneity and isotropy assumptions preclude the use of this standard for continuous fiber reinforced composites. Average grain size(s) should be no greater than one fiftieth (1/50 ) of the C-ring thickness. The curved beam stress solution from engineering mechanics is in good agreement (within 2 %) with an elasticity solution as discussed in (6) for the test specimen geometries recommended for this standard. The curved beam stress equations are simple and straightforward, and therefore it is relatively easy to integrate the equations for calculations for effective area or effective volume for Weibull analyses as discussed in Appendix X1.  
4.2.2 The simple curved beam and theory of elasticity stress solutions both are two-dimensional plane stress solutions. They do not account for stresses in the axial (parallel to b) direction, or variations in the circumferential (hoop, σθ) stresses through the width (b) of the test piece. The variations in the circumferential stresses increase with increases in width (b) and ring thicknes...
SCOPE
1.1 This test method covers the determination of ultimate strength under monotonic loading of advanced ceramics in tubular form at ambient temperatures. The ultimate strength as used in this test method refers to the strength obtained under monotonic compressive loading of C-ring specimens such as shown in Fig. 1, where monotonic refers to a continuous nonstop test rate with no reversals from test initiation to final fracture. This method permits a range of sizes and shapes since test specimens may be prepared from a variety of tubular structures. The method may be used with microminiature test specimens.
FIG. 1 C-Ring Test Geometry with Defining Geometry and Reference Angle (θ) for the Point of Fracture Initiation on the Circumference  
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.2.1 Values expressed in this test method are in accordance with the International System of Units (SI) and IEEE/ASTM SI 10.  
1.3 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.  
1.4 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.

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ASTM
ASTM C1292-22(Test Method)
Standard Test Method for Shear Strength of Continuous Fiber-Reinforced Advanced Ceramics at Ambient Temperatures

SIGNIFICANCE AND USE
5.1 Continuous fiber-reinforced ceramic composites can be candidate materials for structural applications requiring high degrees of wear and corrosion resistance, and damage tolerance at high temperatures.  
5.2 Shear tests provide information on the strength and deformation of materials under shear stresses.  
5.3 This test method may be used for material development, material comparison, quality assurance, characterization, and design data generation.  
5.4 For quality control purposes, results derived from standardized shear test specimens may be considered indicative of the response of the material from which they were taken for given primary processing conditions and post-processing heat treatments.
SCOPE
1.1 This test method covers the determination of shear strength of continuous fiber-reinforced ceramic composites (CFCCs) at ambient temperature. The test methods addressed are (1) the compression of a double-notched test specimen to determine interlaminar shear strength, and (2) the Iosipescu test method to determine the shear strength in any one of the material planes of laminated composites. Test specimen fabrication methods, testing modes (load or displacement control), testing rates (load rate or displacement rate), data collection, and reporting procedures are addressed.  
1.2 This test method is used for testing advanced ceramic or glass matrix composites with continuous fiber reinforcement having unidirectional (1D) or bidirectional (2D) fiber architecture. This test method does not address composites with 3D fiber architecture or discontinuous fiber-reinforced, whisker-reinforced, or particulate-reinforced ceramics.  
1.3 The values stated in SI units are to be regarded as the standard and are in accordance with IEEE/ASTM SI 10.  
1.4 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. Specific hazard statements are given in 8.1 and 8.2.  
1.5 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.

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ASTM
ASTM C1469-22(Test Method)
Standard Test Method for Shear Strength of Joints of Advanced Ceramics at Ambient Temperature

SIGNIFICANCE AND USE
5.1 Advanced ceramics can be candidate materials for structural applications requiring high degrees of wear and corrosion resistance, often at elevated temperatures.  
5.2 Joints are produced to enhance the performance and applicability of materials. While the joints between similar materials are generally made for manufacturing complex parts and repairing components, those involving dissimilar materials usually are produced to exploit the unique properties of each constituent in the new component. Depending on the joining process, the joint region may be the weakest part of the component. Since under mixed-mode and shear loading the load transfer across the joint requires reasonable shear strength, it is important that the quality and integrity of joint under in-plane shear forces be quantified. Shear strength data are also needed to monitor the development of new and improved joining techniques.  
5.3 Shear tests provide information on the strength and deformation of materials under shear stresses.  
5.4 This test method may be used for material development, material comparison, quality assurance, characterization, and design data generation.  
5.5 For quality control purposes, results derived from standardized shear test specimens may be considered indicative of the response of the material from which they were taken for given primary processing conditions and post-processing heat treatments.
SCOPE
1.1 This test method covers the determination of shear strength of joints in advanced ceramics at ambient temperature using asymmetrical four-point flexure. Test specimen geometries, test specimen fabrication methods, testing modes (that is, force or displacement control), testing rates (that is, force or displacement rate), data collection, and reporting procedures are addressed.  
1.2 This test method is used to measure shear strength of ceramic joints in test specimens extracted from larger joined pieces by machining. Test specimens fabricated in this way are not expected to warp due to the relaxation of residual stresses but are expected to be much straighter and more uniform dimensionally than butt-jointed test specimens prepared by joining two halves, which is not recommended. In addition, this test method is intended for joints, which have either low or intermediate strengths with respect to the substrate material to be joined. Joints with high strengths should not be tested by this test method because of the high probability of invalid tests resulting from fractures initiating at the reaction points rather than in the joint. Determination of the shear strength of joints using this test method is appropriate particularly for advanced ceramic matrix composite materials but also may be useful for monolithic advanced ceramic materials.  
1.3 Values expressed in this test method are in accordance with the International System of Units (SI) and IEEE/ASTM SI 10.  
1.4 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. Specific precautionary statements are noted in 8.1.  
1.5 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.

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