BS 7448-3:2005 2007
$198.66
Fracture mechanics toughness tests – Method for determination of fracture toughness of metallic materials at rates of increase in stress intensity factor greater than 3.0 MPa m0.5 s-1
| Published By | Publication Date | Number of Pages |
| BSI | 2007 | 62 |
This part of BS 7448 describes a method for determining the opening mode plane strain fracture toughness KIc, the critical crack tip opening displacement (CTOD) fracture toughness and the critical J fracture toughness of metallic materials. The method uses fatigue precracked specimens tested in displacement control at rates of increase in stress intensity factor greater than 3.0 MPa·m0.5sp1 but less than 3 000 MPa·m0.5sp11) during the initial elastic deformation. Stress intensity factors greater than 3 000 MPa·m0.5sp1 are covered in Annex A. These rates are greater than those permitted in BS 7448-1.
The definition of fracture toughness values relevant to particular structural integrity assessments is outside the scope of this British Standard.
NOTE This standard does not cover integrity assessments. Such assessments are covered in BS 7910.
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 1 | BRITISH STANDARD |
| 2 | Committees responsible for this British�Standard |
| 3 | Contents |
| 7 | 1 Scope 2 Normative references 3 Terms and definitions stress intensity factor opening mode plane strain fracture toughness maximum fatigue stress intensity factor |
| 8 | crack tip opening displacement CTOD critical CTOD J J critical brittle crack extension stable crack extension stretch zone width SZW pop-in |
| 9 | 4 Symbols and designations |
| 11 | 5 Principle |
| 12 | Flow chart for the choice of fracture toughness parameter, specimen design and displacement measu… |
| 13 | 6 Test specimens 6.1 General Proportional dimensions and tolerances for the rectangular section bend specimen |
| 14 | Proportional dimensions and tolerances for the square section bend specimen |
| 15 | Proportional dimensions and tolerances for the straight notch compact specimen |
| 16 | Proportional dimensions and tolerances for the stepped notch compact specimen |
| 18 | Acceptable fatigue crack starter notches and fatigue crack configurations Chevron notch |
| 19 | Outward pointing knife edges and corresponding notch geometrics |
| 20 | Outward pointing knife edges and corresponding notch geometrics 6.2 Choice of specimen design |
| 21 | 6.3 Specimen dimensions necessary for determination of 7 Specimen preparation and fatigue precracking 7.1 Material condition 7.2 Crack plane orientation 7.3 Machining 7.4 Fatigue precracking |
| 22 | Values of for |
| 23 | Values of for 8 Test equipment 8.1 General 8.2 Machine for force application 8.3 System of combined force sensing and recording |
| 24 | 8.4 Displacement measuring devices 8.5 Gauge 8.6 Monitoring and recording equipment 8.7 Thermocouple or platinum resistance thermometer 8.8 Testing fixtures |
| 25 | Fixture for three point bend tests |
| 26 | Typical design of clevis for applying a tensile force to a compact specimen using a circular hole… |
| 27 | Typical design of clevis for applying a tensile force to a compact specimen using a hole with a f… 9 Test procedure 9.1 Specimen measurement |
| 28 | 9.2 Three point bend testing 9.3 Compact tension testing 9.4 Specimen test temperature 9.5 Testing rate 9.6 Recording |
| 29 | Characteristic types of force versus displacement records in fracture tests 9.7 Crack measurements after testing to fracture |
| 30 | 10 Analysis of test data 10.1 General |
| 31 | Assessment of pop-in behaviour 10.2 Determination of plane strain fracture toughness, |
| 33 | Principal types of force versus crack mouth opening gauge displacement records showing the limits… |
| 34 | Force variation limits for fracture toughness determination |
| 35 | Limits of crack mouth opening gauge displacement variations for plane strain fracture toughness d… 10.3 Determination of critical CTOD |
| 36 | Definition of |
| 37 | Limits of force and displacement for CTOD and |
| 39 | Force and load point displacement variation for fracture toughness determination |
| 40 | Displacement variation limits for CTOD and |
| 41 | 10.4 Determination of critical Definition of |
| 44 | 11 Check lists for qualification of data 11.1 Specimen dimensions 12 Test report |
| 46 | (informative) Abbreviated method for determination of dynamic fracture toughness of metallic mate… (informative) Abbreviated method for determination of dynamic fracture toughness of metallic mate… General Principle Determination of the plane strain fracture toughness Determination of critical CTOD |
| 47 | Resistance strain gauge positions for load measurements from rectangular section bend specimen |
| 48 | Limits of loading point displacement variations for CTOD and Determination of the |
| 49 | (informative) Measurement of load-line displacement, (informative) Measurement of load-line displacement, |
| 50 | Schematic representation of the comparator bar Displacements associated with three-point bend specimens |
| 51 | Simultaneous determination of extraneous displacements ( Location of two notch opening displacement measurements ( (normative) Crack plane identification (normative) Crack plane identification |
| 52 | Basic fracture plane identification — Rectangular section Basic fracture plane identification — Cylindrical sections |
| 53 | Non-basic fracture plane identification (normative) Recommended methods for checking response of transducers and recorders (normative) Recommended methods for checking response of transducers and recorders General Check on the system using a dummy specimen |
| 54 | Examples of good and unacceptable force records Examples of good and unacceptable notch opening displacement records Determination of the frequency response of the individual instruments D.C. (electrical resistance strain gauge) signal conditioners and amplifiers |
| 55 | Test system for d.c. signal conditioners and amplifiers Example of the amplitude output of an instrument as a function of frequency |
| 56 | A.C. (linear variable displacement transformer) signal conditioners and amplifiers Test system for a.c. transducers Determination of the frequency response of the notch opening displacement gauge and the load cell |
| 57 | Determination of the response of the electronic parts of the system using a ramp function Conclusions (informative) Abbreviated method for determination of dynamic tensile properties of metallic mate… (informative) Abbreviated method for determination of dynamic tensile properties of metallic mate… General Principle Specimen test temperatures |
| 58 | Determination of the tensile properties and the displacement rate Force versus time record from dynamic tensile test showing no distinct yield point |
| 59 | Force versus time record from dynamic tensile test showing distinct yield point Limits to ram displacement versus time record from dynamic tensile test |
| 60 | Restrictions |
