© Fraunhofer

Non-destructive Testing forLight-weighting

of Automobile Components

info@izfp.fraunhofer.dewww.izfp.fraunhofer.de

ACMA – Fraunhofer Technology Day on

Resource Efficiency in Car Manufacturing

New Delhi, September 8th 2011

Sven Kurzenhäuser

© Fraunhofer

• Introduction: Fraunhofer IZFP

• Application examples of NdT solutions for

• metal working industries

• joining processes

• Summary and conclusions

Contents

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© Fraunhofer

Employees

130 Scientists and engineers

12 Technicians & 29 supportingpersonnel

140 PhD and Diploma students, Research assistantsGuest Scientists

Finances

25.9 Mio € from which

13.8 Mio € by orders from industry

Institute for Non-destructive Testing IZFP at a Glance

Methods and Techniques

Ultrasonic, Eddy Current, Electromagnetics, Micromagnetics, Microwave, x-ray-Radio-scopie, Tomo-, Laminography, Atomic-Force-Mikroscopy, Thermography, Acoustic Emission, Nuclear Magnetic Resonance

Saarbrücken Dresden

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© Fraunhofer

Materials

Components& parts

Manufacturing & joining processes

Quality

AQS - The innovation cluster Automotive Quality Saar

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Metal working

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IZFP Solutions for the Automotive and Supplier Industry

© Fraunhofer 6

Testing of heavy steel plates

Fully-automated inline ultrasonic and micromagnetic testing

� 100% testing of the plate volume since 1998

� 1 m/s production line speed

� Plate thickness 6-60 mm

� Average productivity was 60 000 tons/month

� Detection of faults from 2 mm diameter on

� Detection of „cold ends“ by their anomalous mechanical properties reduces pseudo-scrap

© Fraunhofer

3D-SAFT reconstructed image

0,3-10 MHz

Dynamic 100 dB

12 bit resolution

Line speed 100mm/s

Reconstruction volume 230×135×65 mm3

0,3 mm step size

5 Min (134 MByte)

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Testing of heavy steel plates

Fully-automated inline ultrasonic testing

© Fraunhofer

Detection of pores in Aluminum components

by high-frequency ultrasonic reflection

Detection of subsurface pores and other inclusions by ultrasonic backscattering (above) or high frequency eddy current or thermography

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© Fraunhofer

Ultrasonic systems to evaluate the hardening depth

Evaluation of surface hardening depthby ultrasonic reflection

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© Fraunhofer

Wedge

Coupling (e.g. oil)

Induction hardened layer

Received surface echo

Scattered waves

Received signal of averagedscattered signals

Base material

Ultrasonic Probe

Evaluation of surface hardening depthby ultrasonic reflection - principle

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3MA sensor

Semi-automated system

3MA system

Mechanical properties as hardness, case depth, yield strength, residual or load stress state are correlated to the micromagnetic and electromagnetic material properties, measured by the 3MA system

Evaluation of grinding burns, hardness, internal stresses

... and other quantitative material properties after calibration

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Demands of automotive industry

…increased fuel efficency by lightweightdesign.

… improved chassis stiffness andcrash performance.

High strength steels by press hardening

... enabling superior, tailored properties

High strength steels

Car body and frame requests high

strength boron-manganese steels:

Yield Strength, Hardness, Toughness, Stress State, Homogeneity, Defect Detection, …

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© Fraunhofer

Replacement of destructive testingby non-destructive testing of• Hardness• Yield strength, Rp0.2• Ultimate tensile strength, Rm• Elongation, A50with the 3MA technique and

tool-integrated sensors

Invest: ~ 100 T€

Return of invest in 7 months(for a medium production line)

Online process control during press hardening

... enabling superior, tailored properties of high strength steels

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© Fraunhofer

Characterization of deep drawing processes

by micromagnetics

0.05

0.07

0.09

0.11

0.13

45 50 55 60 65

Stamp path [mm]

ND

T q

uantity

(M

max [V

])

190 kN

230 kN

270 kN

295 kN

320 kN

Stamp force:

Blank break� Tool stamp with integrated 3MA sensor

� In-situ evaluation of material properties

� In-situ evaluation of external and internal stress

� Allows precise control of stamp forces

�Avoids cracks and inhomogenious thickness /necking

Deep drawing machine with integrated sensor

Sensor

Miniaturised3MA sensor

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© Fraunhofer

Active thermography - a flexible NdT solution

...allowing cost-efficent mass testing of parts with various geometries

First certification of active thermography in

Europe, enabling replacement of penetration

testing – i.e. for forged, casted or hardened parts

DIN EN ISO / IEC 17025 : 2005

DAP-PL-3482.00

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3D reconstr. of 100 angle scans (25 s)3D reconstr. of 400 angle scans (100 s)

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High resolution customer specific x-ray systems

Image analysis and evaluation by improved reconstruction algorithms

© Fraunhofer

� 2-D image analysis

� Automated evaluation

� Mixed mode

� Fully integrated in the production line

� Feedback-loop allows fully automated adjustment ofcasting parameters

� 100% testing anddocumentation of parts quality

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X-ray with automated 2D image reconstruction

ISAR - Intelligent System for Automated Radiography

© Fraunhofer

Joining processes

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IZFP Solutions for the Automotive and Supplier Industry

© Fraunhofer

The simultaneous presentation of ultrasonic time-of-flight (green) and the applied torque yields a redundant clamp load evaluation, independent of friction influences

Evaluation of clamp load for process control

Assessment of the clamp load directly at the screw thread

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LASUS systemAutomated ultrasonic system using EMAT (EEEElectroMMMMagnetic Acoustic TTTTransducers) to inspect the laser welds of tailored

blanks

Testing of laser-welded tailored steel (and Al) blanks

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Transducer

X-ray result LASUS result

strong porosity - laser power too high

© Fraunhofer

The undercut determines the quality of the clinch joint.The total wall thickness is a direct measure for the material, pressed into the undercut area.

Undercut

Wall Thickness

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Characterization of clinch strength

by ultrasonic transmission

© Fraunhofer

Parts of a door beam

-134°

-109°

Active thermography, Pulse-Phase-Contrast at 3.5 Hz

Joining line

Indications: to much adhesive applied (left hand side), insufficent line width(center), delamination (right hand side)

Characterization of adhesive joining processes

Enabling material efficency and improved properties

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Summary & Conclusions

Conclusions:

� Demands for higher parts quality and lower costs are not necesarily in contrast

� Process orientation in combination with sophisticated NdT solutions give insight inprocesses and enable innovation

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Summary:

� Various NdT techniques are employed in automotive industry for quality acessment and documentation of product quality

� Increasing demand for in-line NdT systems, not only for defect detection but for acessment of quantitative material properties

� Evaluation of process induced changes of material properties allows control and optimization of manufacturing processes

� By that, an increased resource efficency, light-weighting of parts as well as superior product quality are enabled

© Fraunhofer

Fraunhofer Institute for Non-destructive Testing IZFP

„… we can supply insight…“

© Nick Veasey

Thank you for your attention!

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© Fraunhofer

Evaluation of position and sealing function of adhesive bond seams ofcrimped door beams

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Characterization of adhesive joining processes

Enabling material efficency and improved properties

© Fraunhofer

Multy frequency eddy current system enables the off-line characterization of the final wall thickness of the clinch joint.

0,55

0,60

0,65

0,70

0,75

0,80

0,85

0,90

0,95

0 10 20 30 40 50 60 70 80 90 100 110 120 130

Clinchpunkt

Bodendic

ke [m

m]

Streuung mech. Messwerte: 0,02 mm±

Validation by comparison with results of destructive technique

Characterization of Strength and Process Control IZFP Solutions

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optisches Bild

Millimeterwellenbild, zweidimensionalerScan, 94 GHz-Radar, 120 × 120 mm²

Detektion von Bereichen mit fehlerhafter Faserverteilung an einer Blattfeder aus glasfaserverstärktem Kunststoff (Radaufhängung von Kleinlastern)

Defektdetektion in Glasfaserverbundmaterial

GFK-Blattfeder(Benteler)

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© Fraunhofer

IZFP

Testing of CFRP componentes with Sampling PhasedArray UltrasonicsIZFP Solution

� Detection of production faults

� Characterisation of material damages resulting from impacts

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© Fraunhofer

Conventional PA and Sampling PA-Reconstruction

•Inspection of Composites

•Faster inspection speed

•Pitch-catch mode so less dead zone

•SAFT(Synthetic Aperture Focussing Technique)reconstruction

L

2

x

L

Rückwand

F1F2

F4

Sektorbild

L

2

x

L

F3

Rückwand

F1F2

F4

© Fraunhofer

Prüfung vonHochleistungskeramiken, Schäume, Polymerverbunde

Luft-Ultraschall: Berührungslose Qualitätssicherung neuer Werkstoffe

© Fraunhofer

0.05

0.07

0.09

0.11

0.13

45 50 55 60 65

Stamp path [mm]

ND

T q

uantity

(M

max [V

])

190 kN

230 kN

270 kN

295 kN

320 kN

Stamp force:

Blank break

MagnetikTiefzieh-Regelung

� 3MA-Sensor ist in den Tiefziehstempel integriert

� In-situ Bestimmung der Werkstoffeigenschaften

� In-situ Bestimmung von Eigen-, Lastspannungen

� Regelung (Stempel- Niederhaltekraft, etc.)

�Vermeidung von Rissen, Einschnürungen

Sensor im Stempel einer Tiefziehpresse

Sensor

Miniaturisierter3MA-Sensor

Kernkompetenz

P ü brozess berwachung und - eherrschung

© Fraunhofer

Characterisation of CFRP components by multi-frequency eddy current testing

� Testing frequencies 10Hz – 10MHz, multi-frequency mode by time multiplexing� Directional probes give precise information on squints, missing rovings (1,5,6),suspensions/reverse faults, fraying, fussy balls, extraneus material (3 – test fault), ondulations (4)as well as delaminations (2) in Rohgelegen and CFRPs.

21 3

4 5 6

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Scanwinkel 12°Testfehler: Bohrung ∅ 3 mm

Sampling Phased Array

KonventionellesPhased Array

Ultraschalltechniken

Untersuchung eines CFK-Prüflings

Methoden

Ultraschall

© Fraunhofer

On-line evaluation of wall thickness using ultrasonic technique

Blech-Al-LegierungStahlblech

0 20 40 60 80 100 120 140 160 180 200

Prozesszeit [ms]

1,2

1

0,8

0,6

0,4

0,2

0

Ble

chdic

ke [m

m]

Thi

ckne

ss

Process Time

Characterization of Strength and Process Control IZFP Solutions

© Fraunhofer

MikrowelleGas Assisted Injection Molding (GIT)

� Korrekte Abfolge der Prozessschritte und korrekte Position der Gasblase innerhalb des Hohlkörpers

� Lösung: Miniaturisiertes GIT Überwachungssystem auf Basis eines 94 GHz Radarsensors

� Aufzeichnung der Mikrowellen-Amplitude, -Phase und Frequenz

�Charakteristische Signaländerungen für jeden Prozessschritt

�Detaillierte Prozessüberwachung

Layout der GIT-Prozess-überwachung mit Radarsensor

Charakteristische Signaländerungender einzelnen Prozessschritte

MiniaturisiertesRadarmodul

Kernkompetenz

P ü brozess berwachung und - eherrschung

© Fraunhofer

© Nick Veasey

Fraunhofer Institut für Zerstörungsfreie Prüfverfahren IZFP

„… we can supply insight…“

Thank you for your attention!

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