BS EN ISO 15653:2010 Metallic materials. Method of test for the determination of quasistatic fracture toughness of welds
BS EN ISO 15653 is an international Standard which specifies methods for determining fracture toughness in terms of:
- K (stress intensity factor)
- δ (crack tip opening displacement, CTOD) and
- J (experimental equivalent of the J-integral) for welds in metallic materials.
BS EN ISO 15653 is complementary to BS EN ISO 12135, which covers all aspects of fracture toughness testing of parent metal and which needs to be used in conjunction with this document.
BS EN ISO 15653 describes methods for determining point values of fracture toughness. It should not be considered a way of obtaining a valid R-curve (resistance-to-crack-extension curve). However, the specimen preparation methods described in BS EN ISO 15653 could be usefully employed when determining R-curves for welds.
The methods use fatigue precracked specimens which have been notched, after welding, in a specific target area in the weld. Methods are described to evaluate the suitability of a weld for notch placement within the target area, which is either within the weld metal or within the weld heat-affected zone (HAZ), and then, where appropriate, to evaluate the effectiveness of the fatigue crack in sampling these areas.
Contents of BS EN ISO 15653:
Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Symbols and units
5 Principle
6 Choice of specimen design, specimen orientation and notch location
6.1 Classification of target area for notching
6.2 Specimen design
6.3 Specimen and crack plane orientation
7 Pre-machining metallography
7.1 Microstructural assessment of macrosections
7.2 Additional requirements for heat-affected zone tests
8 Machining
8.1 Tolerances on specimen dimensions
8.2 Notch placement for through-thickness notched specimens
8.3 Notch placement for surface-notched specimens
8.4 Notch machining
9 Specimen preparation
9.1 Fatigue precracking
9.2 Side grooving
10 Test apparatus, requirements and test procedure
11 Post-test metallography
11.1 General
11.2 Through-thickness notched specimens
11.3 Surface-notched specimens
11.4 Assessment of pop-in
12 Post-test analysis
12.1 Choice of tensile properties
12.2 KIc
12.3 δ and J
12.4 Qualification requirements
13 Test report
Annex A (informative) Examples of notch locations
Annex B (informative) Examples of pre-test and post-test metallography
Annex C (normative) Residual-stress modification and precracking technique
Annex D (normative) Assessment of pop-in
Annex E (informative) Shallow-notched specimen testing
Bibliography