Effect of Stress on Ultrasonic Response in Detection and Sizing of Cracks

J. Pitkänen, Anssi Laukkanen, M. Kemppainen, I. Virkkunen

Research output: Contribution to journalArticleScientificpeer-review

Abstract

In different NDT techniques huge developments have been achieved during the last few years with regard to crack detection and sizing. In a large range of materials, cracks are one of the most dangerous defect types. A crack is a planar reflector, which is sometimes extremely difficult to detect and to be sized. A crack can be totally open, partly closed or even totally closed because of compressive stresses. The effects of stresses cause problems, for instance, in in-service inspections of nuclear power plants in detection and sizing of closed cracks. This phenomenon causes similar effects in all kinds of plants and components. In this study some experimental inspections have been carried out as well as some FEM calculations of stress field around the crack and compared to corresponding measurements in literature. Materials used for this study are austenitic and ferritic piping steel. The dynamic load applied to the cracks was in form of different thermal cycles. The maximum temperature variations were from 20°C to 600°C depending on each dynamic loading cycle. Different types of ultrasonic methods were used in the measurements. The effect of closure on the response of normal ultrasonic practical probes was recorded. Dynamic loading during ultrasonic measurement gives clear evidence on the effect of the crack closure as well as on the amplitude variation limits in ultrasonic testing.
Original languageEnglish
Pages (from-to)299-309
Number of pages11
JournalMaterials Testing
Volume49
Issue number6
DOIs
Publication statusPublished - 2007
MoE publication typeA1 Journal article-refereed

Fingerprint

Ultrasonics
Cracks
Inspection
Crack detection
Ultrasonic measurement
Ultrasonic testing
Crack closure
Steel
Dynamic loads
Nondestructive examination
Compressive stress
Nuclear power plants
Finite element method
Defects
Temperature

Keywords

  • ProperTune

Cite this

Pitkänen, J. ; Laukkanen, Anssi ; Kemppainen, M. ; Virkkunen, I. / Effect of Stress on Ultrasonic Response in Detection and Sizing of Cracks. In: Materials Testing. 2007 ; Vol. 49, No. 6. pp. 299-309.
@article{e9c7eea26e50406ea267524cd2f6abba,
title = "Effect of Stress on Ultrasonic Response in Detection and Sizing of Cracks",
abstract = "In different NDT techniques huge developments have been achieved during the last few years with regard to crack detection and sizing. In a large range of materials, cracks are one of the most dangerous defect types. A crack is a planar reflector, which is sometimes extremely difficult to detect and to be sized. A crack can be totally open, partly closed or even totally closed because of compressive stresses. The effects of stresses cause problems, for instance, in in-service inspections of nuclear power plants in detection and sizing of closed cracks. This phenomenon causes similar effects in all kinds of plants and components. In this study some experimental inspections have been carried out as well as some FEM calculations of stress field around the crack and compared to corresponding measurements in literature. Materials used for this study are austenitic and ferritic piping steel. The dynamic load applied to the cracks was in form of different thermal cycles. The maximum temperature variations were from 20°C to 600°C depending on each dynamic loading cycle. Different types of ultrasonic methods were used in the measurements. The effect of closure on the response of normal ultrasonic practical probes was recorded. Dynamic loading during ultrasonic measurement gives clear evidence on the effect of the crack closure as well as on the amplitude variation limits in ultrasonic testing.",
keywords = "ProperTune",
author = "J. Pitk{\"a}nen and Anssi Laukkanen and M. Kemppainen and I. Virkkunen",
year = "2007",
doi = "10.3139/120.100815",
language = "English",
volume = "49",
pages = "299--309",
journal = "Materials Testing",
issn = "0025-5300",
publisher = "Carl Hanser Verlag GmbH & Co. KG",
number = "6",

}

Effect of Stress on Ultrasonic Response in Detection and Sizing of Cracks. / Pitkänen, J.; Laukkanen, Anssi; Kemppainen, M.; Virkkunen, I.

In: Materials Testing, Vol. 49, No. 6, 2007, p. 299-309.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Effect of Stress on Ultrasonic Response in Detection and Sizing of Cracks

AU - Pitkänen, J.

AU - Laukkanen, Anssi

AU - Kemppainen, M.

AU - Virkkunen, I.

PY - 2007

Y1 - 2007

N2 - In different NDT techniques huge developments have been achieved during the last few years with regard to crack detection and sizing. In a large range of materials, cracks are one of the most dangerous defect types. A crack is a planar reflector, which is sometimes extremely difficult to detect and to be sized. A crack can be totally open, partly closed or even totally closed because of compressive stresses. The effects of stresses cause problems, for instance, in in-service inspections of nuclear power plants in detection and sizing of closed cracks. This phenomenon causes similar effects in all kinds of plants and components. In this study some experimental inspections have been carried out as well as some FEM calculations of stress field around the crack and compared to corresponding measurements in literature. Materials used for this study are austenitic and ferritic piping steel. The dynamic load applied to the cracks was in form of different thermal cycles. The maximum temperature variations were from 20°C to 600°C depending on each dynamic loading cycle. Different types of ultrasonic methods were used in the measurements. The effect of closure on the response of normal ultrasonic practical probes was recorded. Dynamic loading during ultrasonic measurement gives clear evidence on the effect of the crack closure as well as on the amplitude variation limits in ultrasonic testing.

AB - In different NDT techniques huge developments have been achieved during the last few years with regard to crack detection and sizing. In a large range of materials, cracks are one of the most dangerous defect types. A crack is a planar reflector, which is sometimes extremely difficult to detect and to be sized. A crack can be totally open, partly closed or even totally closed because of compressive stresses. The effects of stresses cause problems, for instance, in in-service inspections of nuclear power plants in detection and sizing of closed cracks. This phenomenon causes similar effects in all kinds of plants and components. In this study some experimental inspections have been carried out as well as some FEM calculations of stress field around the crack and compared to corresponding measurements in literature. Materials used for this study are austenitic and ferritic piping steel. The dynamic load applied to the cracks was in form of different thermal cycles. The maximum temperature variations were from 20°C to 600°C depending on each dynamic loading cycle. Different types of ultrasonic methods were used in the measurements. The effect of closure on the response of normal ultrasonic practical probes was recorded. Dynamic loading during ultrasonic measurement gives clear evidence on the effect of the crack closure as well as on the amplitude variation limits in ultrasonic testing.

KW - ProperTune

U2 - 10.3139/120.100815

DO - 10.3139/120.100815

M3 - Article

VL - 49

SP - 299

EP - 309

JO - Materials Testing

JF - Materials Testing

SN - 0025-5300

IS - 6

ER -