Detection of defects in bulging processes by means of dynamic laser speckle

Cezary Jasiński , Łukasz Morawiński, Andrzej Kocańda

Warsaw University of Technology, Faculty of Production Engineering, Department of Metal Forming and Foundry, 85 Narbutta St., 02-524 Warsaw, Poland.

DOI:

https://doi.org/10.7494/cmms.2016.1.0555

Abstract:

The method described in this paper has been used to determine the moment when defects appear in the form of strain localization and grooves in the Marciniak bulging tests. In this method based on dynamic laser speckle, the sheet is illuminated by laser. Interference after reflection from the specimen surface creates a characteristic image of bright and dark spots. Specimen surface changes related with deformations and movements cause changes in the shape and size of spots, which are presented by authors in the form of speckle activity image. In order to identify the type of defect, the additional 3D microscopy measurements were performed. This paper presents analysis of the changes in the speckle activity image during the bulging process which enabled the defects identification during the bulging process.

Cite as:

Jasiński, C., Morawiński, Ł., Kocańda, A. (2016). Detection of defects in bulging processes by means of dynamic laser speckle. Computer Methods in Materials Science, 16(1), 12 – 19. https://doi.org/10.7494/cmms.2016.1.0555

Article (PDF):

Keywords:

Sheet metal, bulging, Marciniak test, Vision system, Laser speckle, 3D digital microscope

References:

Dumoulin, S., Louche, H., Hopperstad, O.S., Břrvik, T., 2010,Heat sources, energy storage and dissipation in highstrengthsteels: Experiments and modeling, EuropeanJournal of Mechanics A/Solids, 29, 461-474.

Galpin, B., Grolleau, V., Penin, A., Rio, G., 2016, A hybridmethod for detecting the onset of local necking by monitoringthe bulge forming load, International Journal ofMaterial Forming, 9, 2, 161-173.

Guelorget, B., Francois, M., Vial-Edwards, C., Montay, G.,Daniel, L., Lu, J., 2006, Strain rate measurement byElectronic Speckle Pattern Interferometry: A new lookat the strain localization onset, Materials Science andEngineering: A, 415, 234-241.

Jasiński, C., Morawiński, Ł., Kocańda, A., 2015, Biospekle ipomiary mikroskopowe 3D w detekcji bruzd powstającychw procesach wytłaczania blach, Prace NaukowePolitechniki Warszawskiej – Mechanika, 267, 65-70 (inPolish).

Jasiński, C., 2015, Detekcja lokalizacji odkształceń w procesachwytłaczania blach z wykorzystaniem technik wizyjnych,PhD thesis, Warsaw University of Technology, Warsaw(in Polish).

Kocańda, A., Jasiński, C., 2016, Extended evaluation of Erichsencupping test results by means of laser speckle, Archives ofCivil and Mechanical Engineering, 16, 211-216.

Kocańda, A., Jasiński, C., 2014, Application of laser speckles tolocalized necking and cracking detection in Erichsencupping test, Przegląd Mechaniczny, 9, 49-54.

Morawiński, Ł., 2015, Analiza geometrii pęknięć w procesachgięcia blach z wykorzystaniem technik wizyjnych i symulacjikomputerowych, PhD thesis, Warsaw University ofTechnology, Warsaw (in Polish).

Morawiński, Ł., Kocańda, A., 2015, Influence of tool geometryon surface condition of v-bent aluminum sheet, ComputerMethods in Materials Science, 15, 1, 30-36.

Morawiński, Ł., Jasiński, C., Kocańda, A., 2013, Rekonstrukcjageometrii pęknięć powstałych w blachach w procesachgięcia i wytłaczania przez rozciąganie, Przegląd Mechaniczny,10, 35-39 (in Polish).

Rabal, H. J., Braga, R. A. Jr., 2009, Dynamic Laser Speckle andApplications, CRC Press LLC, Boca Raton.

Relf, C., 2004, Image Acquisition and Processing with LabView,CRC Press LLC, Boca Raton.

Shi, B.-Q., Liang, J., 2012, Circular grid pattern based surfacestrain measurement system for sheet metal forming, Opticsand Lasers in Engineering, 50, 1186-1195.

Turkoz, M., Yigit, O., Dilmec, M., Halkaci, H.S., 2010, Constructionof Forming Limit Diagram for AA 5754 andAA 2024 aluminium alloys, Proceedings of the 12th InternationalConference on Aluminium Alloys, Yokohama,516-521.

Wang, Z-J., Liu, Y., 2010, Investigation on deformation behaviorof sheet metals in viscous pressure bulging based onESPI, Journal of Materials Processing Technology, 210,1536-1544.

Zimniak, Z., Hankiewicz, S., 2006, Badanie magnetyczne procesówtłoczenia blach, Obróbka Plastyczna Metali t.XVII nr 2, Wrocław, 25-31.