BS DD186(1991) : 1991

Foreword
Committees responsible
Method
1. Scope
2. Definitions
3. Main symbols
4. Principle
5. Test equipment
6. Specimens
7. Stress intensity factors
8. Crack length
9. Test procedure
10. Data analysis
11. Test report
Appendices
A. Grips and fixtures
B. Information on methods for measuring crack lengths
C. Stress intensity factor functions
D. Specimen size requirements
E. Flow charts
F. Worked examples of notional tests
G. Accuracy
Tables
1. Toleranced dimensions of specimens
2. Stress intensity factor function values for SENB3
     specimens
3. Stress intensity factor function values for SENB4
     specimens
4. Stress intensity factor function values for CT
     specimens
5. Stress intensity factor function values for CCT
     specimens
6. Growth rate and threshold test at R = 0.1
7. Growth rate and threshold test at R = 0.5
8. Constant K max threshold test
Figures
1. Three-point single edge notch bend specimen (SENB3)
2. Four-point single edge notch bend specimen (SENB4)
3. Compact tension specimen (CT)
4. Centre-cracked tension specimen (CCT)
5. Permitted notch geometries
6. Test fittings for SENB3 specimens
7. Test fittings for SENB4 specimens
8. Recommended test fittings for CT specimens
9. Recommended test fittings for pin-loaded CCT
     specimens
10. Typical steel end-plate design for 250 mm wide
     aluminium alloy centre cracked sheet specimen:
     100 kN maximum load, R > 0
11. Constant R-method; initiation and precracking
12. Constant R-method; threshold and growth rate
     determination
13. Constant K max method; initiation and precracking
14. Constant K max method; threshold determination
15. Delta K history for example 1
16. Delta K history for example 2
17. Crack length versus cycles data for examples 1,2 & 3
18. Crack growth rate versus delta K data for examples
     1 and 2
19. Delta K history for example 3

This draft establishes a method of determining the rates of growth of fatigue cracks as a function of the cyclic range of their stress intensity factors and of determining the threshold stress intensity factor ranges below which the rate of crack growth rapidly becomes infinitesimally small. Covers definitions, main symbols, principle, test equipment, specimens, stress intensity factors, crack length, test procedure, data analysis and test report.