CEN/TS 843-6:2004

Foreword
1 Scope
2 Normative references
3 Terms and definitions
  3.1 General terms
  3.2 Terms classifying inherently volume-distributed
       fracture origins
  3.3 Terms classifying inherently surface-distributed
       fracture origins
  3.4 Terms classifying features on fracture surfaces
4 Significance and use
5 Apparatus
  5.1 Preparation and cleaning facilities
  5.2 Observational facilities
6 Recommended procedure
  6.1 Outline
  6.2 Specimen storage and cleaning of fracture surfaces
  6.3 Visual inspection
  6.4 Optical microscope examination
  6.5 Identification of major fracture surface features
  6.6 Scanning electron microscope examination
  6.7 Identification of fracture origin
  6.8 Identification of chemical inhomogeneity at fracture
       origin
  6.9 Drawing conclusions
7 Report
Annex A (informative) Crack patterns in ceramic bodies
Annex B (informative) Examples of general features of
        fracture surfaces
Annex C (informative) Examples of procedure for fracture
        origin identification
  C.1 Single large pores
  C.2 Agglomerates
  C.3 Large grains
  C.4 Compositional inhomogeneities
  C.5 Delaminations
  C.6 Handling damage
  C.7 Machining damage
  C.8 Oxidation pitting
  C.9 Complex origins
  C.10 No obvious origins
Annex D (informative) Use of fracture mechanical information
        to aid fractography
  D.1 Fracture stress and origin size
  D.2 Fracture stress and fracture mirror size
Annex E (informative) Example layout of reporting pro-forma
Bibliography

This Technical Specification contains guidelines to be adopted when evaluating the appearance of thefracture surface of an advanced technical ceramic. The purpose in undertaking this procedure can bevarious, for example, for material development or quality assessment, to identify normal or abnormalcauses of failure, or as a design aid.NOTE Not all advanced technical ceramics are amenable to fractography. In particular, coarse-grained ceramicscan show such rough surfaces that identifying the fracture origin may be impossible. Similarly, porous materials,especially those of a granular nature, tend not to fracture in a continuous manner, making analysis difficult.