ASTM C1239-13(2018)
Standard Practice for Reporting Uniaxial Strength Data and Estimating Weibull Distribution Parameters for Advanced Ceramics

Standard No.

ASTM C1239-13(2018)

Release Date

2018

Published By

American Society for Testing and Materials (ASTM)

Latest

ASTM C1239-13(2018)

Scope

1.1 This practice covers the evaluation and reporting of uniaxial strength data and the estimation of Weibull probability distribution parameters for advanced ceramics that fail in a brittle fashion (see Fig. 1). The estimated Weibull distribution parameters are used for statistical comparison of the relative quality of two or more test data sets and for the prediction of the probability of failure (or, alternatively, the fracture strength) for a structure of interest. In addition, this practice encourages the integration of mechanical property data and fractographic analysis. 1.2 The failure strength of advanced ceramics is treated as a continuous random variable determined by the flaw population. Typically, a number of test specimens with well-defined geometry are failed under isothermal, well-defined displacement and/or force-application conditions. The force at which each test specimen fails is recorded. The resulting failure stress data are used to obtain Weibull parameter estimates associated with the underlying flaw population distribution. 1.3 This practice is restricted to the assumption that the distribution underlying the failure strengths is the twoparameter Weibull distribution with size scaling. Furthermore, this practice is restricted to test specimens (tensile, flexural, pressurized ring, etc.) that are primarily subjected to uniaxial stress states. The practice also assumes that the flaw population is stable with time and that no slow crack growth is occurring. 1.4 The practice outlines methods to correct for bias errors in the estimated Weibull parameters and to calculate confidence bounds on those estimates from data sets where all failures originate from a single flaw population (that is, a single failure mode). In samples where failures originate from multiple independent flaw populations (for example, competing failure modes), the methods outlined in Section 9 for bias correction and confidence bounds are not applicable. 1.5 This practice includes the following: Section Scope 1 Referenced Documents 2 Terminology 3 Summary of Practice 4 Significance and Use 5 Interferences 6 Outlying Observations 7 Maximum Likelihood Parameter Estimators for Competing Flaw Distributions 8 Unbiasing Factors and Confidence Bounds 9 Fractography 10 Examples 11 Keywords 12 Computer Algorithm MAXL Appendix X1 Test Specimens with Unidentified Fracture Origins Appendix X2 1.6 The values stated in SI units are to be regarded as the standard per IEEE/ASTM SI 10. 1.7 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 C1239-13(2018) Referenced Document

• ASTM C1145 Standard Terminology of Advanced Ceramics
• ASTM C1322 Standard Practice for Fractography and Characterization of Fracture Origins in Advanced Ceramics
• ASTM E178 Standard Practice for Dealing With Outlying Observations
• ASTM E456 Standard Terminology for Relating to Quality and Statistics
• ASTM E6 Standard Terminology Relating to Methods of Mechanical Testing
• IEEE/ASTM SI 10 American National Standard for Metric Practice

ASTM C1239-13(2018) history

• 2018 ASTM C1239-13(2018) Standard Practice for Reporting Uniaxial Strength Data and Estimating Weibull Distribution Parameters for Advanced Ceramics
• 2013 ASTM C1239-13 Standard Practice for Reporting Uniaxial Strength Data and Estimating Weibull Distribution Parameters for Advanced Ceramics
• 2007 ASTM C1239-07 Standard Practice for Reporting Uniaxial Strength Data and Estimating Weibull Distribution Parameters for Advanced Ceramics
• 2006 ASTM C1239-06a Standard Practice for Reporting Uniaxial Strength Data and Estimating Weibull Distribution Parameters for Advanced Ceramics
• 2006 ASTM C1239-06 Standard Practice for Reporting Uniaxial Strength Data and Estimating Weibull Distribution Parameters for Advanced Ceramics
• 2000 ASTM C1239-00(2005) Standard Practice for Reporting Uniaxial Strength Data and Estimating Weibull Distribution Parameters for Advanced Ceramics
• 2000 ASTM C1239-00 Standard Practice for Reporting Uniaxial Strength Data and Estimating Weibull Distribution Parameters for Advanced Ceramics