scholarly journals Study on the Measurement of Laser Drilling Depth by Combining Digital Image Relationship Measurement in Aluminum

Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 489
Author(s):  
Chao-Ching Ho ◽  
Guan-Hong Li
Keyword(s):  
Digital Image Correlation ◽  
Digital Image ◽  
Laser Processing ◽  
Correlation Method ◽  
Experimental Results ◽  
Image Correlation ◽  
Detection Methods ◽  
Coefficient Of Determination ◽  
Drilling Depth ◽  
Hole Depth

In this study, laser processing equipment was used to drill aluminum alloy materials and with different auxiliary mechanisms, the deformation around the holes after processing was observed. The experimental results show that, due to the high temperature generated during laser processing, a large thermal gradient causes thermal stress to be introduced into the test piece and outward expansion deformation occurs. In this study, the digital image correlation and residual stress detection methods were applied. Based on the correlation between the drilled hole depth and the hole deformation, the hole depth of the laser processing was estimated. The average coefficient of determination for all auxiliary mechanisms is 0.82. The experimental results confirm that the digital image correlation method can be used to estimate the hole depth of laser processing.

scholarly journals Preliminary Experimental and Numerical Study of Metal Element with Notches Reinforced by Composite Materials

2021 ◽  
Vol 5 (5) ◽  
pp. 134
Author(s):  
Paweł J. Romanowicz ◽  
Bogdan Szybiński ◽  
Mateusz Wygoda
Keyword(s):  
Digital Image Correlation ◽  
Digital Image ◽  
Numerical Study ◽  
Correlation Method ◽  
Industrial Applications ◽  
Experimental Results ◽  
Image Correlation ◽  
Stress Concentrations ◽  
Element Analysis ◽  
Wide Range

The presented study is related to the application of the composite overlays used in order to decrease the effect of the stress concentrations around the cut-outs in structural metal elements. The proposed approach with the application of the digital image correlation extends the recently presented studies. Such structural elements with openings of various shapes have been accommodated for a wide range of industrial applications. These structures exhibit certain stress concentrations which decrease their durability and strength. To restore their strength, various reinforcing overlays can be used. In the present paper, the flat panel structure without and with the composite overlays made of HEXCEL TVR 380 M12/26%/R-glass/epoxy is under the experimental and the numerical study. Particular attention is paid to the investigation of the samples with the rectangular holes, which for smooth rounded corners offer a higher durability than the samples with the circular hole of the same size. The experimental results are obtained for the bare element and are reinforced with composite overlay samples. The experimental results are obtained with the use of the Digital Image Correlation method, while the numerical results are the product of the Finite Element Analysis. In the numerical analysis, the study of the shape, size and fiber orientation in applied overlays is done. The reduction of the stress concentration observed in opening notches has confirmed the effectiveness of the overlay application. In the investigated example, the application of the square composite overlay increased the structure strength even by 25%.

Two-Steps Digital Image Correlation and Application to Studies of Micromechanics Behavior of Coating Interface

2007 ◽  
Vol 336-338 ◽  
pp. 1810-1813
Author(s):  
Jin Long Chen ◽  
Quan Yu Liu ◽  
Yu Wen Qin ◽  
Xin Hua Ji
Keyword(s):  
Digital Image Correlation ◽  
Base Metal ◽  
Digital Image ◽  
Spline Interpolation ◽  
Compressive Strain ◽  
Correlation Method ◽  
Experimental Results ◽  
Image Correlation ◽  
Different Thickness ◽  
Better Than

In this paper, two-steps digital image correlation method is well advanced with the sub-pixel reconstruction in sub-image by utilizing the higher precision calculation of bicubic spline interpolation value method, and the accuracy of displacement is extended to better than 0.01 pixel, the strain resolution is limited to less than 0.0002 in micro-region. The experimental results show that the method of two-steps digital image correlation is an up-to-date technique to comprehensive investigations of base metal-coating composition at extremely small size scales. In the meantime, influence of crack in base metal perpendicular to interface on coating is directly observed, and the measurement of the residual compressive strain in base metal is performed according to different thickness of coatings. Lastly, the bond behavior between base metal and coating has been quantitatively analyzed, and the experimental results also prove the Ni-Lan coating is combined with base metal by toughened interface.

The Analysis of Different Stochastic Patterns during Loading in Plastic Area Using DIC Method

2014 ◽  
Vol 611 ◽  
pp. 490-495
Author(s):  
Martin Schrötter ◽  
Martin Hagara ◽  
Matúš Kalina
Keyword(s):  
Digital Image Correlation ◽  
Digital Image ◽  
Correlation Method ◽  
Mean Value ◽  
Image Correlation ◽  
Black And White ◽  
Unloaded State ◽  
Measured Deformation ◽  
The Mean ◽  
Estimated Error

The aim of this article is to present the influence of stochastic pattern on results accuracy of digital image correlation method in plastic areas. The various types of stochastic patterns were applied on testing specimens which were then tensioned. There was correlated the intensity of black and white color (denoted as grey value) dispersed on a specimen, then the mean value of estimated error for unloaded state as well as state of highest measured deformation and finally the amount of non-correlated facets. Also the maximal deformation of specimens was compared by which the damage of stochastic pattern emerged.

The Stress Intensity Factor of Opening Mode Determined by Digital Image Correlation

2011 ◽  
Vol 83 ◽  
pp. 54-59 ◽  
Author(s):  
Rui Zhang ◽  
Ling Feng He ◽  
Chang Rong Li
Keyword(s):  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Digital Image Correlation ◽  
Intensity Factor ◽  
Digital Image ◽  
Correlation Method ◽  
Compact Tension ◽  
Image Correlation ◽  
Full Field ◽  
Opening Mode

Applications of the digital image correlation method (DIC) for the determination of the opening mode stress intensity factor (SIF) is investigated using an edge cracked aluminum plate in this paper. Standard compact tension test specimen was tested under tensile loading and the full-field displacement fields of the test sample were recorded using DIC. The SIF associated with unavoidable rigid-body displacement translation were calculated simultaneously from the experimental data by fitting the theoretical displacement field using the method of least-squares. Selection of displacement and convergence values is discussed. For validation, the SIF thus determined is compared with theoretical results, confirming the effectiveness and accuracy of the proposed technique. Therefore it reveals that the DIC is a practical and effective tool for full-field deformation and SIF measurement.

Sign in / Sign up

Export Citation Format

Share Document