EN 3873:2010

Aerospace series - Test methods for metallic materials - Determination of fatigue crack growth rates using Corner-Cracked (CC) test pieces

This standard specifies the requirements for determining fatigue crack growth rates using the corner-crack (CC) test piece. Crack development is measured using a potential-drop system, and the calculated crack depths can be corrected via marker bands created on the fracture surface during the test. Results are expressed in terms of the crack-tip stress-intensity range (K), with crack depths and test stress level noted.

Luft- und Raumfahrt - Prüfverfahren für metallische Werkstoffe - Ermittlung der Rissfortschritts- Geschwindigkeit an Cornercrackproben (Eckanris)

Diese Norm legt die Anforderungen für die Bestimmung der Geschwindigkeit des Ermüdungswachstums unter
Verwendung von Eckanriss-Proben (Corner-Crack, CC) fest. Die Rissentwicklung wird mit einem
Potentialabfallsystem gemessen, und die berechneten Risstiefen können über Markierungsbänder, die im
Verlauf der Prüfung an der Bruchfläche erzeugt wurden, korrigiert werden. Die Ergebnisse werden in Form
der Schwingbreite der Rissspitzen-Spannungsintensität (ΔK) dargestellt, wobei die Risstiefen und das
Prüfspannungsniveau aufgezeichnet werden.

Série aérospatiale - Méthodes d'essais applicables aux matériaux métalliques - Détermination de la vitesse de propagation de fissure en fatigue à l'aide d'éprouvettes avec fissure en coin

Aeronavtika - Preskusne metode za kovinske materiale - Ugotavljanje stopnje rasti razpok, ki nastanejo zaradi utrujenosti, z uporabo preskusnih kosov z razpokami na robovih (CC)

Ta standard določa zahteve za ugotavljanje stopnje rasti razpok, ki nastanejo zaradi utrujenosti, z uporabo preskusnega kosa z razpokami na robovih (CC). Razvoj razpok je merjen z uporabo sistema za potencialni padec, izračunana globina razpoke pa je lahko popravljena z označevalnimi pasovi, narejenimi na razpokani površini med preskusom. Rezultati so izraženi v izrazih za razpon intenzivnosti napetosti konice razpoke (K), z globino razpoke in upoštevano stopnjo preskusne napetosti.

General Information

• Status: Published
• Publication Date: 02-Nov-2010
• Withdrawal Date: 30-May-2011
• ICS: 49.025.05 - Ferrous alloys in general
• ICS: 49.025.15 - Non-ferrous alloys in general
• Technical Committee: ASD-STAN - Aerospace
• Drafting Committee: ASD-STAN/D 4 - Metallic
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 03-Nov-2010
• Completion Date: 03-Nov-2010
• Ref Project: SIST EN 3873:2011 - Aerospace series - Test methods for metallic materials - Determination of fatigue crack growth rates using Corner-Cracked (CC) test pieces

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Aeronavtika - Preskusne metode za kovinske materiale - Ugotavljanje stopnje rasti razpok, ki nastanejo zaradi utrujenosti, z uporabo preskusnih kosov z razpokami na robovih (CC)Luft- und Raumfahrt - Prüfverfahren für metallische Werkstoffe - Ermittlung der Rißfortschritts- Geschwindigkeit an Cornercrackproben (Eckanris)Série aérospatiale - Méthode d'essais applicables aux matériaux métalliques - Détermination de la vitesse de propagation de fissure en fatigue à l'aide d'éprouvettes avec fissure en coinAerospace series - Test methods for metallic materials - Determination of fatigue crack growth rates using Corner-Cracked (CC) test pieces49.025.05Železove zlitine na splošnoFerrous alloys in generalICS:Ta slovenski standard je istoveten z:EN 3873:2010SIST EN 3873:2011en01-maj-2011SIST EN 3873:2011SLOVENSKI
STANDARD
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 3873
November 2010 ICS 49.025.05; 49.025.15 English Version
Aerospace series - Test methods for metallic materials - Determination of fatigue crack growth rates using Corner-Cracked (CC) test pieces
Série aérospatiale - Méthodes d'essais applicables aux matériaux métalliques - Détermination de la vitesse de propagation de fissure en fatigue à l'aide d'éprouvettes avec fissure en coin
Luft- und Raumfahrt - Prüfverfahren für metallische Werkstoffe - Ermittlung der Rißfortschritts-Geschwindigkeit an Cornercrackproben (Eckanris) This European Standard was approved by CEN on 30 July 2010.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre:
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B-1000 Brussels © 2010 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 3873:2010: ESIST EN 3873:2011

Information on measuring crack depths in corner-crack test pieces with the direct-current − Potential-drop method . 18Annex B (normative)
Stress-intensity function for corner-crack test pieces
............................................ 22Annex C (normative)
Guidelines on test piece handling and degreasing . 24SIST EN 3873:2011

1) Published by: American Society for Testing and Materials (ASTM), http://www.astm.org/. SIST EN 3873:2011

Effective range of K, due to crack closure-induced reduction applied ∆K (in MPa √m) ∆Kth Fatigue crack growth threshold
The asymptotic value of ∆K for which da/dN approaches zero. For most materials the operational threshold is defined as the ∆K corresponding to 10-7 m/cycle. When reporting ∆Kth, the corresponding lowest decade of near threshold data used in its determination must be given C Normalized K-gradient C = (1/K × dK/da). For load-shedding to attain a desired initial ∆K, C defines the fractional rate of change of K with increasing crack depth a.
C = 1/K × dK/da = 1/Kmax. × dKmax./da = 1/Kmin. × dKmin./da = 1/∆K × d∆K /da, (in mm-1) N Number of loading cycles Stress cycle (fatigue cycle, load cycle) is the smallest segment of the loading waveform spectrum which is repeated periodically N'
Number of stress cycles between two marker cycles Nm Number of stress cycles in a marker cycle ∆N Stress cycle difference r Notch radius (expressed in millimetres) Fm Mean force (expressed in kilonewtons) Fmax. Maximum tensile force applied to the test piece during a cycle (expressed in kilonewtons) Fmin. Minimum tensile force (in kilonewtons) ∆F Force range (in kilonewtons), ∆F = Fmax. − Fmin. q Resolution of crack depth measuring system (expressed in millimetres) R Force ratio (= Fmin./Fmax. = Kmin./Kmax.) R*m Ratio Fmin./Fmax. during a marker cycle Rp 0,2 % offset yield strength (Proof Stress Rp0,2) at test temperature (expressed in megapascals) SIST EN 3873:2011

(3) 4.6 The reference point for measuring the crack depth with CC test pieces is the original corner of the test piece, determined by the projections of the sides of the test piece on the fracture surface adjacent to the notch. Possible rounding of the corner during test piece manufacture will result in this reference point being no longer on the fracture surface. This rounding must be determined to obtain a “Zero-point offset” between the reference point and the rounded corner where the measurement wire is welded, which is used in the calibration of the potential-drop measurements. SIST EN 3873:2011
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