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Induction Thermography: Influence of testing parameters for Different Crack Geometry 1

SEM Annual Conference and Exposition on Experimental and Applied Mechanics

作者： De Vanna, Davide D'Accardi, Ester Dell'Avvocato, Giuseppe Palumbo, Davide Galietti, Umberto Polytech Univ Bari Dept Mech Math & Management Bari Italy

ISBN: (数字)9783031504709

ISBN: (纸本)9783031504723;9783031504709;9783031504693

In recent years, induction thermography has been proposed to detect and characterize shallow and open cracks on steel components. The specimen is inspected by an infrared camera that records the heating and cooling behavior after a short induced electrical current pulse. The presence of a crack changes the distribution of the induced eddy currents with a consequent more significant local heating around the region of interest than the related sound one. This work investigates the influence of the testing parameters with an experimental approach, considering the analysis of a ferromagnetic master specimen with imposed simulated open cracks of different depths. The influence of the relative position between the coil and simulated crack has been evaluated, considering both numerical and experimental results. Two different coils have been adopted to optimize the experimental tests in terms of inspection time and improve the signal-to-noise ratio. It has been demonstrated that the post-processing of the raw thermal data is necessary to have useful information about defect detection for a pulse duration of 10 ms with only 20 A. A linear relationship exists between the phase contrast and the nominal defect depth.

关键词： Induction thermography Non-destructive testing (NDT) Simulated cracks testing parameters Post-processing algorithms

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SEALING ABILITY OF CEMENT PLUGS: INVESTIGATION OF CRITICAL testing parameters 43

SEALING ABILITY OF CEMENT PLUGS: INVESTIGATION OF CRITICAL T...

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ASME 43rd International Conference on Ocean, Offshore and Arctic Engineering (OMAE)

作者： Opedal, Nils Feneuil, Blandine Wiggen, Even Haug, Jakob N'Gouamba, Elie Skorpa, Ragnhild SINTEF Ind Trondheim Norway

ISBN: (纸本)9780791887868

Determination of a sealant material's ability to provide zonal isolation is important. Any potential well barrier material should ideally be tested and optimized under controlled, reproducible, and relevant conditions. Recent advances in experimental methods for qualification of materials beyond the API-10 standard have been published. For further development, the critical testing parameters relevant for these test methods should be investigated. The objective of this paper was to study the effect of test conditions such as cement curing time and scale dimensions. The curing and test conditions were found to be potentially important factors to ensure reproducible data and for understanding what is actually measured from the setup. For instance, the mechanical strength of cement might not be an adequate proxy to determine the hydraulic bond strength of a material. Also, the experimental determination of sealability of cement to a steel casing is dependent on several factors, such as curing time, presence of water during the cement hydration process, the cement plug dimensions, and the testing protocol itself.

关键词： P&A Cement plug Zonal isolation testing parameters

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Response surface methodology for optimizing LIBS testing parameters: A case to conduct the elemental contents analysis in soil

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CHEMOMETRICS AND INTELLIGENT LABORATORY SYSTEMS 2019年 195卷 103891-000页

作者： Yu, Keqiang Zhao, Yanru He, Yong He, Dongjian Northwest A&F Univ Coll Mech & Elect Engn 22 Xinong Rd Yangling 712100 Shaanxi Peoples R China Minist Agr & Rural Affairs Key Lab Agr Internet Things Yangling 712100 Shaanxi Peoples R China Shaanxi Key Lab Agr Informat Percept & Intelligen Yangling 712100 Shaanxi Peoples R China Zhejiang Univ Coll Biosyst Engn & Food Sci 866 Yuhangtang Rd Hangzhou 310058 Zhejiang Peoples R China

Optimization of testing parameters are the prerequisite for laser induced breakdown spectroscopy (LIBS) further data analysis, which can offer important reference value for the soil detection in the field. This work investigated the influence of the main testing parameters laser energy (LE), delay time (DT), and lens to sample distance (LTSD) of LIBS system. Based on the spectral characteristic of main elements in soils, the testing parameters of LIBS for soil detection were obtained and verified. The optimization analysis of three testing parameters LE (50-160 mJ), DT (0.5-4.5 mu s), and LTSD (94-102 mm) were conducted by response surface methodology (RSM). Central composite design (CCD) in RSM was introduced to carry out experimental runs. The combined signal-background-ratio (SBR) of characteristic spectral lines from main elements (Si, Fe, Mg, Ca, Al, Na, K, etc.) in soil were defined as the objective function (named Y-SBR). The interaction influences among three independent variables (LE, DT, and LTSD) on soil plasma characteristics were explored and the optimized testing parameters of LIBS were summarized. Results revealed as follows: the factor LE showed a remarkable linear effect to Y-SBR, and factors DT and LTSD exhibited opposite results. The interactive items of three factors displayed a non-significant relationship. Meanwhile, the quadratic items of LE2, DT2 and LTSD2 offered significant surface relationships. Through the RSM analysis, the optimized testing parameters for LIBS soil detection were LE: 103.09 mJ;DT: 2.92 mu s;LTSD: 97.69 mm;and a peak value Y-SBR of 198.60. After that, the LIBS data of 21 representative soil samples were collected under the optimized LIBS testing parameters. Partial least squares regression (PLSR) was introduced to predict the main elemental contents. Results indicated that PLSR models offered promising outputs for predicting the contents of Al, Ca, Fe, K, Mg, and Na in the sampled soil, which revealed that the testing par

关键词： Laser-induced breakdown spectroscopy Soil Response surface methodology testing parameters Emission lines

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Lithium Disilicate Restorations Fatigue testing parameters: A Systematic Review

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JOURNAL OF PROSTHODONTICS-IMPLANT ESTHETIC AND RECONSTRUCTIVE DENTISTRY 2016年第2期25卷 116-126页

作者： Nawafleh, Noor Hatamleh, Muhanad Elshiyab, Shareen Mack, Florian Griffith Univ Sch Dent & Oral Hlth Nathan Qld 4111 Australia Kings Coll Hosp NHS Fdn Trust Cranio Maxillofacial Prosthet Unit London England

PurposeTo review laboratory studies that investigated fatigue resistance of lithium disilicate (LD) crowns and fixed dental prostheses (FDPs) to elucidate study designs and testing parameters. MethodsAn electronic search was performed in PubMed, Scopus, and Ovid to identify in vitro studies that investigated fatigue resistance of LD crowns and FDPs. The search included all studies published in English in peer-reviewed journals in the period from 1998 to June 2014. The search followed a specific strategy that included combination of the following keywords: lithium disilicate, ***, empress, all-ceramic, all ceramic, glass ceramic, fatigue, cyclic loading, dynamic loading, chewing simulator, fracture resistance, thermocycling, laboratory simulation, aging, crown, FDPs, FPDs, fixed partial denture, fixed dental prosthesis, and bridge. Studies were selected if mechanical and thermal loading parameters were clearly identified. Search results with abstracts were transferred into Endnote reference system, and duplicates were deleted. The remaining studies were then reviewed at three levels (title, abstract, full text) to further refine the articles. ResultsThe initial search retrieved 1044 eligible studies. After deduplication, 864 records were examined by titles and then abstracts;826 were excluded, and 38 were assessed by full-text reading. In total, 19 articles met inclusion criteria and were included in this study. ConclusionThe studies reviewed showed a level of heterogeneity, as testing parameters were considered through different setups. The current study demonstrated that various setting of the testing parameters and having a lack of testing standardization has likely led to inconsistency in the reported results. The obvious heterogeneity in the setting of testing variablesespecially the magnitude of load and number of cycles appliedmade it impractical to run direct comparisons between the reviewed studies. Therefore, specific international standardization of fati

关键词： Cyclic loading chewing simulator thermocycling laboratory simulation testing parameters

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ACS APPLIED NANO MATERIALS 2025年第22期8卷 11682-11691页

作者： Yang, Luobai Liu, Wenxiang Zhao, Dongye Xizang Univ Coll Sci Key Lab Plateau Oxygen & Living Environm Xizang Au Lhasa 850000 Peoples R China

To achieve efficient hydrogen production through water electrolysis, in recent years, more scholars have used nickel foam (NF) as a self-supporting material to grow various nanomaterial electrocatalysts, such as layered double hydroxides (LDHs), achieving high current densities. However, currently, for testing the performance of NF grown with various nanomaterials, the testing parameters vary greatly across different literature studies, such as the tested area of NF, solution concentration, and solution stirring rate, and this leads to the electrocatalytic performance of NF being overly simplified. Neglecting the influence of these properties on catalyst electrocatalytic performance during testing makes it difficult to accurately evaluate the electrocatalytic activity of nanomaterials on the NF surface. To standardize the assessment of the electrocatalytic performance of nanomaterials, it is essential to understand the influencing parameters, which include the types of counter and reference electrodes, the solution characteristics, the testing area of NF, and the properties of NF.

关键词： water splitting nickel foam nanomaterialelectrocatalysts testing parameters standardizedassessment

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Comparative analysis of single-and multiple-frequency thermal wave radar imaging inspection of glass fiber reinforced polymer(GFRP)

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International Journal of Extreme Manufacturing 2022年第2期4卷 161-172页

作者： Lishuai Liu Andreas Mandelis Alexander Melnikov Liming Wang Key Laboratory of Pressure Systems and Safety of MOE School of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237People’s Republic of China Center for Advanced Diffusion-Wave and Photoacoustic Technologies(CADIPT) Department of Mechanical and Industrial EngineeringUniversity of TorontoTorontoON M5S 3G8Canada Institute for Advanced Non-Destructive and Non-Invasive Diagnostic Technologies(IANDIT) TorontoONM5S 3G8Canada Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055People’s Republic of China

Active infrared thermography has gained increasing popularity for nondestructive testing and evaluation in various industrial fields,especially for composite *** this regard,thermal wave radar(TWR)imaging is recognized as the next-generation active thermography technology to obtain great resolution and depth range over the inspected objects.A critical aspect concerns the optimal test parameter selection to guarantee reliable quality assurance required for industrial *** this work,single-and multiple-frequency TWR was investigated in a quantitative manner with the goal of optimizing the detection parameters in terms of probing range and lateral and depth *** effects of test parameters,including sampling frequency,modulation frequency,chirp duration,chirp bandwidth,etc,were investigated in detail through experiments on a glass fiber reinforced polymer specimen with multi-scale diameter-to-depth ratio *** paper aims to help yield a better understanding of the physical mechanism behind TWR and propose a workable scheme for testing parameter selection in practical applications.

关键词： GFRP thermal wave radar testing parameters nondestructive testing

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Recent developments in the determination of fatigue crack propagation thresholds

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INTERNATIONAL JOURNAL OF FATIGUE 2022年 164卷

作者： Duarte, Larissa Schoenherr, Josef Arthur Madia, Mauro Zerbst, Uwe Geilen, Max Benedikt Klein, Marcus Oechsner, Matthias Bundesanstalt Mat Forsch & Prufung BAM Div 9-4Unter Eichen 87 D-12205 Berlin Germany Tech Univ Darmstadt Ctr Struct Mat MPA IfW Grafenstr 2 D-64283 Darmstadt Germany

The impact of crack closure and environmental effects on the experimental determination of the fatigue crack propagation threshold is a major problem for the assessment of cyclically loaded components, especially low stress ratios . In this work, the influence of the experimental procedure and air humidity on d/d data at different is discussed. Unlike the results at = -1, the threshold values obtained at & AP;0.8, i.e. under negligible crack closure levels, show a very small scatter band regardless of the variation of the test parameters and environmental conditions.

关键词： Fatigue crack propagation threshold Component assessment Crack closure Environmental effects testing parameters

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A study on the viscoelastic behaviors of tire cords using dynamic mechanical analysis

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JOURNAL OF ENGINEERED FIBERS AND FABRICS 2020年第15期15卷

作者： Tian, Liyong Wang, Di Su, Peng Wei, Qufu Jiangnan Univ Key Lab Ecotext Minist Educ 1800 Lihu Ave Wuxi 214122 Jiangsu Peoples R China Performance Fibers Kaiping Co Ltd Kaiping Peoples R China

Design of experiments was adopted to evaluate the effect of selected test parameters on the viscoelastic behaviors of polyester tire cords through dynamic mechanical analysis systematically. Design of experiments results showed that temperature, static load, and dynamic amplitude had significant effects on the responses of complex modulus (E*) and Tan delta. Furthermore, temperature had significant interactions with static load and dynamic amplitude factors on the responses. None of the test parameters had any significant effect on the response of glass transition temperature (T-g). Below T-g, thermoplastic tire cords exhibited a high and constant dynamic modulus, whereas, beyond this point, the modulus decreased dramatically. The thermosetting tire cords exhibited a constant performance due to an ordered and tight molecular chain arrangement. The magnitude of Tan delta reached its peak value at T-g due to the increase in internal friction as a result of increasing temperature. The dynamic modulus increased and Tan delta decreased with the increasing static load as a result of restricting the mobility of chain segments. The reverse was true when the dynamic amplitude increased, most probably because of higher chain segment mobility and early stage of polymer chain slippage. Activation energy (E-a), derived from Arrhenius equation, can be used to predict its long-term performance. T-g shifted to a higher temperature as the frequency increased. In addition, by increasing the twist level of the polyester tire cord, the dynamic modulus decreased and Tan delta increased. Tg was evaluated as the upper limit working temperature, Tan delta was related to energy dissipation, and E* determined the overall performance of the tire cord. By displacing T-g to a higher temperature, reducing the magnitude of Tan delta and increasing the dynamic modulus are of great importance to a tire cord's performance.

关键词： Viscoelastic properties tire cord testing parameters design of experiments dynamic mechanical analysis

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Methodologies for the analysis of antimicrobial effects of immobilized photocatalytic materials

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APPLIED MICROBIOLOGY AND BIOTECHNOLOGY 2014年第5期98卷 1925-1936页

作者： Zvab, Urska Stangar, Urska Lavrencic Marusic, Martina Bergant Univ Nova Gorica Environm Res Lab Nova Gorica 5000 Slovenia Univ Nova Gor Ctr Biomed Sci & Engn Vipava 5271 Slovenia

Photocatalytic coatings are considered sustainable materials as they only need sunlight for their activation and regeneration. Some photocatalytic disinfecting coatings are already commercialized, but many more are still in the developmental stage. Efficient and reliable analytical methodologies for testing the antimicrobial effects of photocatalytic coatings should therefore be used and further developed (1) to avoid inactive or unstable final products, (2) to allow fast, reproducible, and inexpensive antimicrobial activity measurements, and (3) to reflect real environmental conditions and challenges for these materials. Aiming to improve the existing methodologies of antimicrobial testing, this mini review summarizes and discusses the testing parameters and procedures in this expanding research field, including research on antimicrobial activity of photocatalytic coatings for different applications, i.e., self-cleaning/disinfecting coatings (films) and photocatalytic coatings for water and air treatment/disinfection.

关键词： Photocatalytic coatings Antimicrobial activity testing parameters Detection methods

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Information and Measurement System for Control of Technical State of Asynchronous Electric Motors with Group Supply from Frequency Converter 12

Information and Measurement System for Control of Technical ...

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12th International Conference on Actual Problems of Electronics Instrument Engineering (APEIE)

作者： Radionov, A. A. Evdokimov, S. A. Karandaev, A. S. Khramshin, V. R. Natl Res South Ural State Univ Chelyabinsk Russia Nosov Magnitogorsk State Tech Univ Magnitogorsk Russia

ISBN: (纸本)9781479960200

The paper substantiates the significance of continuous control of the asynchronous motor technical state and diagnostic troubleshooting with group supply from the frequency converters. It also provides rationale for combined application of the stationary and mobile monitoring systems with the example of asynchronous motors in the roller table units of the Magnitogorsk Iron and Steel Works plate mill 5,000;as well as identifies their technical features. The paper substantiates requirements for functional configuration of the stationary system, considers its hardware providing compatibility with the Lab VIEW NATIONAL INSTRUMENTS software. The developed software is specified, too. The cross-correlation function and signal-to-noise ratio of the phase current are rationally considered as the major testing parameters. The paper also justifies performance of spectrum and current analysis of input currents. It provides the window of the application for visualization and storage of the electric drive operating condition data. The technical state of electric motors of roller tables tested is assumed and their proper functioning is established.

关键词： Asynchronous motor group supply from the frequency converter technical state monitoring testing parameters

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