Monitoring the FSW Processes Using a Multispectral Vision Method

The FSW method is a modern and still not very common method for joining materials by mixing them after plasticising with a special tool. The rotary motion of the tool and its pressure against the welded surface causes friction and, as an effect, local heating of the material that then causes plasticisation. Then the tool moves linearly along the trajectory of welding, while the stem causes the mixing of materials and tool’s shoulder concentrates and presses the material in the produced weld. An important feature of the process is that the material does not pass to the liquid phase and remain in the solid phase. This method allows the combination of non-welding and difficult to weld materials, including combining different materials (dissimilar). The FSW method is a new method and there are no tools to assess the quality of the process, especially on-line, that is in the making of the weld. Currently, the research methods used include point temperature measurement and measurement of forces on the tool performed during welding, and metallographic methods that are destructive can be used after the weld. This article presents the authors’ method for monitoring the Friction Stir Welding (FSW) processes with use of a multi-spectral vision method. The monitoring method uses the system built of two visual channels that work in different light bands; hence, the name of the method ismulti-spectral.The main component of the system is an infrared camera that is used for the observation of the temperature distribution on the surface of the welded materials. The second visual channel uses the line-scan visual band camera for recording the image of the surface of the weld. Such observation allows the detection of weld defects and non-compliances, which include excessive burrs, discontinuities, uneven edge of the weld, as well as the subsurface faults such as cavities and sub-surface discontinuities. In addition, the temperature of the process is monitored to prevent under-and over-heating, which may result in a weak joint or cracks in the material. The presented method is applied for monitoring the FSW process and presents a worldwide novelty.

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Monitoring the FSW Processes with Use of Thermal Imaging

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.220-221.859 ◽

2015 ◽

Vol 220-221 ◽

pp. 859-863 ◽

Cited By ~ 1

Author(s):

Jordan Mężyk ◽

Szymon Kowieski

Keyword(s):

Friction Stir Welding ◽

Thermal Imaging ◽

Infrared Imaging ◽

Solid Phase ◽

Practical Application ◽

Thermal Imaging Camera ◽

Friction Stir ◽

Imaging Camera ◽

On Line

Friction stir welding (FSW) is a recently developed method for making a rigid joint of materials that are otherwise hard to weld. It uses a rotating tool for softening the materials without reaching the melting point, and while the tool is moved along the joint line the plasticised material from the joined materials is mixed and hardened producing the solid phase bond. The article presents the authors’ method for monitoring the Friction Stir Welding (FSW) processes with use of thermal imaging camera.FSW method is a new method and there are only few tools to assess the quality of the process, especially on-line, that is in the making of the weld. The authors propose a method for monitoring the FSW process using hybrid vision methods that is acquisition of the image of the weld with the use of a thermal imaging camera and visual band camera. The paper presents selected results of research performed using infrared imaging channel.The recorded thermograms allow identifying the weld defects and non-compliances during the process and using a thermal imaging camera, also allow detecting subsurface defects. The obtained results indicate its potential practical application but still the described application is to be further developed to become a part of a hybrid system for monitoring the FSW processes.

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Effect of two types of ozone treatments on the quality of apple fruits

Acta Universitatis Cibiniensis Series E Food Technology ◽

10.2478/aucft-2021-0026 ◽

2021 ◽

Vol 25 (2) ◽

pp. 285-292

Author(s):

Maciej Balawejder ◽

Natalia Matłok ◽

Wioletta Sowa ◽

Natalia Kończyk ◽

Tomasz Piechowiak ◽

...

Keyword(s):

Solid Phase ◽

Control Sample ◽

Antioxidant Potential ◽

Main Component ◽

Water Saturated ◽

Gallic Acid Equivalent ◽

Ozonation Process ◽

Gaseous Form ◽

Ozonated Water

Abstract The aim of this research was to demonstrate the effect of the ozonation process (exposure to ozone in gaseous form and rinsing in water saturated with ozone) on selected apple parameters. The scope of the study included: conducting the ozonation process under controlled conditions at a concentration of 1 ppm and exposure times of 1, 5 and 10 min (ozone in gaseous form) and 10, 15 and 30 min (ozonated water), respectively; polyphenols research; determining antiradical activity using ABTS radicals; and determining the influence of the applied method on the volatiles that give rise to odor chemicals (fragrance and aroma). In both cases, measurements were taken 24 hours after the ozonation process. Both exposure to ozone in gaseous form and washing in ozonated water did not adversely affect the appearance of the fruit. The rinsing process in ozonated water did not significantly affect the composition of the compounds responsible for the fruit’s odor. The proposed washing conditions affected the biochemical balance of the fruit. Differences in polyphenol content and antioxidant potential were noted. The mean content of polyphenols expressed as gallic acid equivalent in the control sample was determined to be 15.22 mg/100 g. In comparing the content of polyphenols with the control sample, insignificant changes in their content were noted, except for the sample with the longest ozonation. In the case of fruit washed within 30 minutes, a significant increase by 53% in antioxidant potential was noted. α- Farnesene was identified as the main component established by headspace solid-phase microextraction (HS-SPME) procedure. The proposed ozonation conditions made it possible to keep the volatile compounds influencing the sensory properties of apples unchanged.

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Sensor Fusion and On-Line Monitoring of Friction Stir Blind Riveting for Lightweight Materials Manufacturing

Volume 3: Manufacturing Equipment and Systems ◽

10.1115/msec2018-6507 ◽

2018 ◽

Author(s):

Zhe Gao ◽

Weihong Guo ◽

Jingjing Li

Keyword(s):

Feature Extraction ◽

Sensor Fusion ◽

Process Monitoring ◽

Classifier Fusion ◽

Lasso Regression ◽

Monitoring Method ◽

Lightweight Materials ◽

Friction Stir ◽

Feature Extraction And Selection

Friction stir blind riveting (FSBR) is a recently developed manufacturing process for joining dissimilar lightweight materials. The objective of this study is to gain a better understanding of FSBR in joining carbon fiber-reinforced polymer composite and aluminum alloy sheets by developing a sensor fusion and process monitoring method. The proposed method establishes the relationship between the FSBR process and the quality of the joints by integrating feature extraction, feature selection, and classifier fusion. This study investigates the effectiveness of lower rank tensor decomposition methods in extracting features from multi-sensor, high-dimensional, heterogeneous profile data. The extracted features are combined with process parameters, material stack-up sequence, and engineering-driven features such as the peak force to provide rich information about the FSBR process. Sparse group lasso regression is adopted to select the optimal monitoring features. The selected features are fed into weighted classification fusion to estimate the quality of the joints. The fusion method integrates five individual classifiers with optimal weights. The correct classification rates resulted from various feature extraction and selection methods are assessed and compared. The proposed method can also be applied to other manufacturing processes with online sensing capabilities for the purpose of process monitoring and quality prediction.

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