P. Holler· V. Hauk· G. Dobmann C. O. Ruud . R. E. Green (Eds.)

Nondestructive Characterization of Materials Proceedings of the 3rd International Symposium Saarbriicken, FRG October 3-6, 1988

Organized by

Deutsche Gesellschaft fur zerstorungsfreie Priifung e.Y. (DGZiP), Berlin and Fraunhofer-Institut fur zerstorungsfreie Priifverfahren (!ziP), Saarbriicken

With 609 Figures

Springer-Verlag Berlin Heidelberg New York London Paris Tokyo Hong Kong

Prof. Dr. Paul Holler Fraunhofer Institut fUr zerstorungsfreie Priifverfahren Universitat, Gebaude 37 6600 Saarbriicken 11 FRG

Dr. G. Dobmann Fraunhofer Institut fUr zerstorungsfreie Priifverfahren Universitat, Gebaude 37 6600 Saarbriicken 11 FRG

Robert E. Green, Jr. Center for Nondestructive Evaluation The Johns Hopkins University Baltimore, Maryland 21218 USA

Prof. Dr. Viktor Hauk Institut fUr Werkstoffkunde Rhein. Westf. Technische Hochschule 5100 Aachen FRG

Prof. Dr. Clayton O. Ruud 159 Materials Research Laboratory The Pennsylvania State University University Park, Pennsylvania 16802 USA

ISBN -13: 978-3-642-84005-0 e- ISBN-13 :978-3-642-84003-6 DOl: 10.1007/978-3-642-84003-6

This work is subject to copyright. All rights are reseIVed, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, re-use of illustrations, recitation, broadcasting, reproduction on microfilms or in otherways,and storage in data banks. Duplication ofthis publication or parts thereofis only permitted under the provisions of the German Copyright Law ofSeptember9, 1965, in its version of June 24, 1985,and a copyright fee must always be paid. Violations fall underthe prosecution act of the German Copyright Law.

© Springer-Verlag Berlin Heidelberg 1989 Softcoverreprint of the hardcover 1st edition 1989

The use of registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and there­fore free for general use.

216113020543210

Preface

Engineering structures for reliable function and safety have to be

designed such that operational mechanical loads are compensated for by

stresses in the components bearable by the materials used. Vhat is

"bearable"? First of all it depends on the properties of the chosen

materials as well as on several other parameters, e.g. temperature,

corrosivity of the environment, elapsed or remaining serviceable life,

unexpected deterioration of materials, whatever the source and nature of

such deterioration may be: defects, loss of strength, embrittlement,

wastage, etc. DEFECTS and PROPERTIES of materials currently determine

loadability. Therefore in addition to nondestructive testing for defects

there is also a need for nondestructive testing of properties.

The third type of information to be supplied by nondestructive

measurement pertains to STRESS STATES under OPERATIONAL LOADS, i.e.

LOAD-INDUCED plus RESIDUAL STRESSES. Residual stresses normally cannot be

calculated; they have to be measured nondestructively; well-approved

elastomechanical finite element codes are available and used for

calculating load-induced stresses; for redundancy and reliability,

engineers, however, need procedures and instrumentation for experimental

checks.

Three quantitative ndt-categories should be available for the

qualification and/or quality assurance of structures during fabrication and

operation:

- ndt for DEFECTS (ndtd)

- ndt for PROPERTIES (ndtp)

- ndt for STRESSES (ndts)

Ndtd and ndts are much further developed and more frequently applied

than ndtp. In addition, the technical communities for ndtd and ndts are

much larger than that for ndtp. National and international ndt conferences

deal far more with ndtd than ndts and ndtp. In November 88 the second

International Conference on Residual Stresses was held in Nancy (less than

60 miles from SaarbrUcken), at which 205 papers were presented and with 280

participants attending. Most contributions dealt with just one

ndts-technique, X-RAY DIFFRACTION. Second place was occupied by relaxation

techniques in which residual stresses are partially released by drilling

holes or machining notches. Releasing strain is measured by arrays of small

strain gauges (rosettes). For shallow bore holes or notches this RELAXATION

TECHNIQUE is at most slightly destructive. Both techniques, X-ray

diffraction and relaxation, measure strains which are directly related to

the stress states to be measured by the second order elastic moduli.

Unfortunately the major mechanical properties describe the nonelastic

i.e. nonreversible -- behaviour of materials, which physically is not

correlated to elastic behaviour; however, only testing in the elastic area

is nondestructive. Consequently, it is due to physical reasons that ndtp is

not possible for MECHANICAL properties in a direct manner as ndtd is for

defects and ndts for stresses. (Nevertheless elastic moduli have become

important ndt quantities; they carry information pertaining to the

stiffness and microstructure of materials. Several papers were presented on

this subject during the symposium). Other physical properties such as

nonelastic mechanical properties -- electric, thermal, magnetic, etc.

can be measured using ndt techniques. They strongly correlate with the

microstructure of materials.

Macroscopic nonelastic properties and behaviour of materials, especially

metals, physically depend on solid solutions (alloys), microstructure

(dislocations, precipitations, etc.) and stresses. Physical metallurgy

deals with these dependencies and will continue research on them as long as

optimization and development of materials exist.

The situation at present: we do not have nd testing methods offering

direct access to macroscopic mechanical properties and describing behaviour

under loads,' however, we do have nd testing technology for microstructure

(and microstresses). Moreover, physical metallurgists have the know-how to

derive macroscopic properties from microstructural data measured

nondestructively.

The scenario described above is illustrated by two diagrams. The first

diagram shows microstructural parameters and defects relevant to strength

VII

and toughness of materials plotted against their linear dimensions, resulting in the resolution needed for nondestructive materials characterization. A wide band from 10-10 to 10- 2 is covered; the most important area for metals and ceramics and composites as well is 10- 9 to 10- 5 • In the second diagram ndt techniques are plotted with the same abscissa. There are more ndt techniques for microstructures and defects above 10- 5 than below; but those below 10- 5 already provide access to the most important microstructures relevant for mechanical properties and early stages of deterioration.

The nondestructive characterization (ndc) of materials by

electromagnetic techniques was born at least 50 years ago. A few names of pioneers, for laboratory applications as well as for industrial testing should be mentioned (in alphabetical order): W.A. Black, F. Forster, W.

Gerlach, W. Jellinghaus, H. Lange. One of these pioneers, F. Forster, has accepted our invitation to present a paper on the origin of electromagnetic

methods.

It is the merit of C.O. Ruud and R.E. Green that a series of symposia devoted to nondestructive materials characterization was started in 1983. This first symposium, held in Hershey Pennsylvania, was a considerable success. The same holds true for the second symposium, organized by J.F.

Bussiere in Montreal. During a meeting of the organizing committee and the international advisory board held during the second symposium the representatives of several countries indicated their willingness and

interest to host and organize the third symposium. The decision was made in favour of Saarbrlicken, FRG.

The 3rd IS-NDC, organized by the DGZfP and the FhG-IzfP, was conducted in Saarbrlicken from October 3-6, 1988. 225 scientists from 14 different countries took part. 81 oral presentations were given, 15 of them were invited plenary lectures and 37 poster presentations complementing the

comprehensive program. The panel discussion involving P. Adam, G. Nardoni, H. Schneider, M. G. Seitz, Ch. Thoma, F. TOnolini and R. Zeller was chaired by D. O. Thompson. R. Sharpe gave an evaluation of the conference in his

concluding speech along with providing an outlook for future objectives and development trends.

VIII

We would like to especially thank the numerous ladies and gentlemen of

the staffs at the DGZfP, Berlin, and at the Institut fUr zerstorungsfreie

prUfverfahren, SaarbrUcken, for their untiring efforts in helping to

organize and conduct this symposium. We would also like to extend our

thanks to the members of the international advisory board and the

organizing and program committees.

The present proceedings volume contains 103 articles submitted by the

authors. This represents the current level of knowledge in the field of Nne

of materials. The editors would like to thank the authors for adhering to

the restrictions on length imposed. This means that they were forced to

concentrate on essential results, dispense with details and supplementary

work. We would like.to thank Springer Verlag for their efforts in quickly

publishing the volume.

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Table of Contents

1. Research Programmes

2.

3.

Y.van der Eijk H.Pero

Y.Faul

Ceramics

H.Schmidt

T.Kishi K.Kitadate

E.Brinksmeier H.Siemer H.G.Yobker

P.S.Nicholson

J.Goebbels H.Heidt B.Illerhaus P.Reimers

G.Schlieper V.Arnhold H.Dirkes

Y.Sachse K.Y.Kim

Composites

S.Datta H.Ledbetter

D.Y.Fitting A.V.Clark

M.J.Ehrlich J.Y.Yagner

Presentation of the next BRITE-EORAH-Programme (1989-1992) ••.••.•••••••••••••••••••••••••••••.•••••• 3

Materials Research-Programme of the Federal Ministry for Research and Technology (BMFT) •••••••••• 8

Properties, preparation and requirements to testing of ceramic materials ••••••••••••••••••••.••• 17

Material characterization of ceramics by various nondestructive testing methods .••••••••••••• 26

Requirements on nondestructive testing methods after machining of ceramics ••••••••••••••••••••••••• 36

Ultrasonic nde of advanced ceramics ••••••••••••••••. 46

Tomodensitometry with x- and gamma-rays ••••••••••••. 56

Nondestructive density measurements in powder metallurgy and ceramics ••••••••••••••••••••••••••••• 65

New developments for the ultrasonic character-ization of materials •••••••••••••••••••••••••••••••• 73

Graphite-magnesium elastic constants: Composite and fiber ••••••••••••••••••••••••••••••••• 83

Monitoring of anisotropic material elastic properties using ultrasonic receiving arrays •••••••• 91

Anisotropy measurements and indication of ply orientation in composite materials using holo­graphic mapping of large amplitude acoustic waves ••••••••••••••••••••••••••••••••••••••••••••••• 99

XII

K.Yamaguchi H.Oyaizu

B.Briihl

A.Jungmann L.Adler G.Quentin

J.F.de Belleval Y.Boyer D.Lecuru

M.P.Hentschel A.Lange

M.Maisl T.Scherer H.Reiter S.Hirsekorn

L.F.Bresse D.A.Hutchins B.Farahbakhsh

G.Ibe

D.F.Lee K.Salama E.Schneider

S.Hirsekorn

F.Corvasce P.Lipinski M.Bervdller

4. Polymers

V.Hauk, A.Troost D.Ley

G.Busse D.Vergne

P.Elsner

F.Twardon O.Leitzbach G.Busse

Recognition of fracture modes and behaviour of composites by acoustic emission •••••••••••••••••••• 107

Determination of strength properties of injection moulded parts made from reinforced thermoplastics by acoustic emission ••••••••••••••••••••••••••••••• 118

Ultrasonic velocity measurements in porous ma terials •••••••••••••••••••••••••••••••••••••••••• 122

Porosity characterization in thin composite plates by ultrasonic measurements •••••••••••••••••• 131

X-ray diffraction scanning microscopy - a new method of nondestructive characterization of composi tes ••••••••••••••••••••••••••••• , ••••••••••• 140

Nondestructive investigation of fibre rein-forced composites by x-ray computed tomography ••••• 147

Ultrasonic characterization of aluminium/epoxy composi te materials •••••••••••••••••••••••••••••••• 155

Fibre and particle reinforced metal matrix com­posites: structure - production - properties ••••••• 163

Ultrasonic characterization of SiC-reinforced aluminum ••.•••••••••••••••••••••••••••••••••••••••• 173

Ultrasonic propagation in metal-matrix-composi tes ••••••••••••••••••••••••••••••••••••••••• 184

Thermomechanical behaviour of metal matrix composi tes •.•••••••••••••••••••••••••••••••••••••••• 194

Correlation between manufacturing parameters and residual stresses of injection-molded poly­propylene: an x-ray diffraction study •••••••••••••• 207

Characterization of varnish layers using opti-cally generated thermal waves •••••••••••••••••••••• 215

Application of dielectric spectroscopy for non­destructive investigation of epoxy curing •••••••••• 223

The investigation of mass transport through polyethylene with concentration waves •••••••••••••• 232

5. Texture

H.J.Bunge

H.J.Bunge

C.O.Ruud D.J.Snoha

H.-G.Brokmeier H.J.Bunge

F.Vagner H.Otten H.J.Kopineck H.J.Bunge

S.Hirsekorn E.Schneider

M.Spies E.Schneider

O.Cassier C.Donadi1le B.Bacroix

Y.Li J.F.Smith R.B.Thompson

XIII

Texture analysis - a method of non-destructive characterization of materials I •••••••••••••••.•••• 241

Texture analysis - a method of non-destructive characterization of materials II ••••••••••••••.••.• 252

Characterization of crystallographic texture in aluminum can stock by x-ray diffraction •••••••••••• 267

Non-destructive determination of materials parameters by neutron diffraction •••••••••••••••••• 273

Computer aided optimization of an on-line texture analyzer ••.•••••••••••••••••••••••••••••••• 281

Characterization of rolling texture by ultra-sonic dispersion measurement ••••••••••••••••••••.•• 289

Nondestructive analysis of the deep-drawing behaviour of rolled sheets with ultrasonic techniques ••••••••••.•••••••••••••••••••••••••••••• 296

Lankford coefficient evaluation in steel sheets by an ultrasonic method •••••••••••.•••••••••••••••• 303

Characterization of textures in plates by ultrasonic plate wave velocities ••••••.•••••••••.•• 312

6. Microstructure, Stress State, Creep Damages

H.-A.Crostack V.Reimers U.Selvadurai G.Eckold

A.Morsch V.Arnold

S.Fa&bender M.Kulakov B.Hoffmann M.Paul H.Peukert V.Arnold

A.Le Brun J.L.Lesne O.Cassier F.Goncalves D.Ferriere

Surveillance of material degradation by means of diffraction methods ••••••••••••••••••••••••••••• 323

Grain-size measurements by spectral evaluation of line-scans in scanning acoustic microscopy •••••• 331

Non-contact and nondestructive evaluation of grain-sizes in thin metal sheets ••••••••••••••••••• 337

The use of a contactless ultrasonic method for evaluating grain size in steel sheets •••••••••••.•• 345

XIV

J.F.Bussiere L.Piche G.Leclerc

H.Ledbetter S.Datta

R.L.Smith T.E.Dixon

B.Z.Jang H.B.Hsieh M.D. Shelby

A.Morsch D.Korn H.Gleiter M.Hoppe 11'. Arnold

F.Lakestani P.Rimoldi

S.Ekinci A.N.Bilge

C.O.Ruud G.H.Pennington E.M.Brauss S.D.II'eedman

Z.Pawlowski

R.E.Schramm P.J.Shull A.V.Clark, Jr. D.V.Mitrakovic

K.KuBmaul A.Ettemeyer

H.Jorgens H.\I'iessiolek

H.Ruppersberg M.Eckhardt

P.Sirotti P.Demanins

E.J.Tucholski R.E.Green, Jr.

Analysis of the effect of graphite morphology on the elastic properties of cast iron .....•.•..... 353

Effect of graphite aspect ratio on cast-iron elastic constants .•.......•....•..•..•.....•.•..... 361

Ultrasonic determination of materials characteristics ..•.•...•.•.......•.•.••...•.•.•...• 368

Real time cure monitoring and control of com­posite fabrication using nondestructive dyna-mic mechanical methods •.•.•..•.•..•.••...•.•.•..•.. 376

Characterization of the elastic behaviour of nanocrystalline materials by scanning acoustic microscopy .......•.•...•.•.•.....•....•...•.•.•...• 384

Variation of the ultrasonic propagation velo-city due to creep strain in austenitic steel .•..•.. 391

Application of ultrasonic methods for the cha­racterization of Zr02 pellets .••..•.•...••.•.•....• 398

Simultaneous residual stress and retained austenite measurement by x-ray diffraction .•....... 406

Acoustic characteristics of porous materials in simple and complex state of stresses .•.•.•..•...••. 413

Crack inspection of railroad wheel treads by EMATs .•.•...•.•..•.•.....•.•.•..•....•............. 421

Computer aided threedimensional deformation analysis using holographic interferometry ...•.•...• 429

Practical application of ultrasonic stress ana-lysis on thin walled components ••...•.•.•..•••.•..• 438

Stress field in a cold-rolled nickel plate deduced from diffraction experiments performed with synchrotron radiation at varied penetra-tion depths .•.•...•...•..•...•..••...•.•.•.....•••. 442

A hybrid computer for phase images visualiza-tion and correlation based recognition .....•.•.•... 450

Three dimensional surface representations of linear-elastic anisotropy in cubic single crys-tals •.•.•......•......•..........•.....•.•..•...... 458

V.Hauk P.H611er R.Oudelhofen V.A.Theiner

H.Veber

N.Kasik

H.-A.Crostack V.Beckmann V.Bischoff R.Niehus

7. Electromagnetics

F.F6rster

G.Dobmann V.A.Theiner R.Becker

D.C.Jiles p.Garikepati

S.S.Lee S.Lee

R.E.Beissner

V.Morgner J.Gomez

I. Komine K.Nishifuj i

K.Grotz B.Lutz

H.A.Crostack V.Bischoff J.Nehring

P.J.Shull A.V.Clark B.A. Auld

R.Zorgati A.Bernard F.Pons B.Duchene D.Lesselier V.Tabbara

xv

Determination of shot peened surface states using the magnetic Barkhausen noise method ••••••••• 466

Development of creep damages on heatresistant ferritic steel •••••.•••••••••••••.••••••••••••••••• 474

Nondestructive metallurgical investigations for the evaluation of turbines ••••••••••••••••••••••••• 486

Early recognition of creep damages by means of nondestructive test methods •••••••••••••••••••••••• 495

The origin of nondestructive determination of characteristic material parameters using electro-magnetic methods ••••••••••••••••••••••••••••••••••• 505

Progress in the micromagnetic multiparameter microstructure and stress analysis (3MA) ••••••••••• 516

Detection of stress in steels from differential magnetic susceptibility •••••••••••••••••••••••••••• 524

Nondestructive characterization of austempered ductile irons •••••••••••••••••••••••••••••••••••••• 532

Theory of eddy current characterization of mag-netic conductors ••••••••••••••••••••••••••••••••••• 541

Nondestructive approach to characterizing the strength and structure of cast iron •••••••••••••••• 549

Nondestructive measurement of mechanical pro-perties of steel plates •••••••••••••••••••••••••••• 557

Simultaneous electromagnetic determination of various material characteristics ••••••••••••••••••• 565

Nondestructive testing of forged components using CS-pulsed eddy-current technique ••••••••••••• 574

Applications of capacitive array sensors to nondestructive evaluation •••••••••••••••••••••••••• 582

Modelling of the electromagnetic field diffracted by an inhomogeneity in metal: A first step in magnetic imaging ••••••••••••••••••• 590

XVI

R.Kern V.A.Theiner P.Schaaf U.Gonser

LAltpeter R.Kern P.HoUer

V.Staib H.KUnzel

G.MauBner A.Seibold

G.Dobmann H.Pitsch

R.Koch P.HoUer

Comparative micromagnetic and Mossbauer spec­troscopic depth profile analysis of laserhar-dened steel X210Cr12 .•.....•.......•.•.••...•...... 598

Characterization of cementite in steel and white cast iron by micromagnetic nondestructive methods ...•.••.•....••.•.•...••.......•.•....•..•.. 606

In-situ ferrite content measurement of duplex steel structures in the chemical industry. Practical applications of the alternating field, magnetoinductive method .•.•....•.••.•.•.•..•.•..•.. 614

Changes in magnetic and mechanical properties and microstructure during annealing of the stain­less soft martensitic steel X 5 CrNi 13 4 (1.4313) ..•.•..••...•..•...•.........•.•..•.•.•.... 622

Magnetic tangential field-strength-inspection, a further ndt-tool for 3MA ..........•........••...• 636

A modulus for the evaluations of the dynamic magnetostriction as a measured quantity of the 3MA method ..•..........•.•................•........ 644

8. Nuclear Magnetic Resonance (NM&)

G.A.Matzkanin

K.Gersonde

A review of nondestructive characterization of composi tes using NMR ....•.•....•..•...•.•....•..•.. 655

Tissue characterization by NMR in medical diag­nostics (published by Springer Verlag in Proc. of the Int. Symp. CAR 87(1987), p. 402-407)

9. Instruments and Systems Process Control

R.Herzer E.Schnei~er

A.Vilbrand V.Repplinger G.HUbschen H.-J.Salzburger

J.B.Spicer J.V.Vagner

V.A.Theiner B.Reimringer H.Kopp M.Gessner

Instrument for the automated ultrasonic time­of-flight measurement - a tool for materials characterization ...•..•.•.......••.......••..••.••• 673

EMUS-systems for stress and texture evaluation by ultrasound •........•.•.•.•.••..•...•....•.•...•. 681

Fiber-optic based heterodyne interferometer for noncontact ultrasonic determination of acoustic velocity and attenuation in ma terials ....•..........•...•..............•.•..••. 691

The 3MA-testing equipment, application possi-bilities and experiences •...•.......•....•.•.•....• 699

H.-U.Mast T.Brandler E.Knorr P.Stein

D.C.Jiles

A.C.Yey L.Y.Kessler R.Y.Chiao

J.P.Panakkal H.Peukert H.Yillems

H.-J.Kopineck

H.-J.Kopineck H.Otten H.J.Bunge

G.V.Blessing D.G.Eitzen

J.M.Yinter, Jr. R.E.Green, Jr.

P.B.Nagy A.Yexler L.Adler M.Talmant

C.K.Jen J.F.Bussiere Ph.de Heering P.Sutcliffe

XVII

Small neutron radiography systems and their applications •••••••••••••••.••••••••••••••••••••••• 707

Multiparameter magnetic inspection system for nde of ferromagnetic materials •••••••••••••..•••••• 715

Development of new quantitative SLAM techniques for material evaluation •••••••••••••••••••••••••••• 723

Nondestructive characterization of material properties by an automated ultrasonic technique •••• 731

Industrial application of on-line texture meas-urement •.••••••••.••••••••••••••••••••••••••••••••• 740

On-line measuring of technological data of cold and hot rolled steel strips by a fixed angle texture-analyzer ••••••••••••••••••••••••••••••••••• 753

Ultrasonic measurements of surface roughness ••••••• 763

Characterization of industrially important materials using x-ray diffraction imaging methods ••.••••••••••••••••••••••••••••••.••••••••.• 771

Ultrasonic characterization of cold welds •••••••••• 780

Ultrasonic monitoring of the molten zone during float zone refining of single crystal germanium •••• 788

10. Optical and Thermal Properties, Special Techniques

K.L.Telschow R.J.Conant

M.Beyfuss J.Baumann

B.S.Ramprasad T.S.Radha E.S.R.Gopal

H.-A.Crostack V.Beckmann H.-J.Storp

Optical parameter effects on laser generated ultrasound for microstructure characterization ••••• 799

Determination of the thermal properties of thin layers by a photothermal technique ••••••••••••••••• 807

Laser speckle photography for the measurement of changes in refractive index in phase media •.•••• 817

Testing of coatings by means of acoustic emission •.•••••..•••••••••••••••••••••••••••••••••• 825

XVIII

J.P.Panakkal J.K.Ghosh P.R. Roy

Y.K.Park J.O.Lee S.Lee

K.lbendorf A.Hinz V.Schroter

J.A.Johnson N.M.Carlson

J.Baumann P.Klofac G.Fritsch

U.Kiefer K.-D.Becker V.Gebhardt F.Valte

A.C.Boccara F.Charbonnier D.Fournier P.Robert

R.S.Sharpe

Nondestructive characterization of mixed oxide pellets in welded nuclear fuel pins by neutron radiography and gamma-autoradiography ..•.•.•..••... 832

Nondestructive characterization of a deformed steel using positron annihilation .•.•......••.••... 839

Ambulante elektrochemische Charakterisierung metallischer und metalloider Festkorperober-fliichen ..•.•••...••..•.•...•...•.•....••.•.•..•.•.• 846

Noncontact ultrasonic sensing of weld pools for automated welding .••.•.•.•.•.•.•.•...•..•••..••.••• 854

Accurate determination of the focal spot size of a micro focus x-ray tube •.......•.•......•..••... 862

Characterization of ultrasonic probes with physical and parametric methods ••...•.••.•.•.••...• 870

Mirage effect and optical reflectance: New improvements in nondestructive evaluation ..•..••... 878

Clos ing Commen ts ....••.•.•••.•.•.•.•.•....•.••..••. 886