Accession Number:

ADA021065

Title:

An Error Analysis of Failure Prediction Techniques Derived from Fracture Mechanics.

Descriptive Note:

Interim rept. 1 Jul-30 Dec 75,

Corporate Author:

NATIONAL BUREAU OF STANDARDS WASHINGTON D C INST FOR MATERIALS RESEARCH

Personal Author(s):

• Wiederhorn,S. M.
• Fuller,E. R. , Jr.
• Mandel,J.
• Evans,A. G.

Report Date:

1975-12-01

Pagination or Media Count:

42.0

Abstract:

Three principal methods of failure prediction for brittle materials are analyzed statistically. Each method depends on fracture mechanics for its predictive value and hence, the variance of the failure time is found to depend on the scatter in the fracture mechanics data and the scatter in the estimate of the initial size of the strength limiting crack. The variance is used to calculate confidence limits for the prediction of failure for two materials, glass and silicon carbide. Procedures for the collection and analysis of data are discussed, and the implications of the analysis for lifetime prediction are evaluated.

Descriptors:

• *GLASS
• *FRACTURE(MECHANICS)
• *SILICON CARBIDES
• CERAMIC MATERIALS
• RELIABILITY
• CRACK PROPAGATION
• BRITTLENESS
• MATHEMATICAL PREDICTION
• ERRORS
• LEAST SQUARES METHOD
• STATISTICAL ANALYSIS
• COVARIANCE
• REFRACTORY MATERIALS

Subject Categories:

• Ceramics, Refractories and Glass

Distribution Statement:

APPROVED FOR PUBLIC RELEASE