Development of a nondestructive method for testing the strength of concrete based on the phenomenon of mechanoelectric transformations

2012 ◽  
Author(s):  
Tatyana Fursa ◽  
Konstantin Osipov
Keyword(s):  
Nondestructive Method ◽  
Mechanoelectric Transformations

Diagnostics of Fibre-Reinforced Concrete by the Nondestructive Method Based on Mechanoelectric Transformations Phenomenon

2019 ◽  
Vol 970 ◽  
pp. 236-241
Author(s):  
Maxim V. Petrov ◽  
Denis D. Dann
Keyword(s):  
Reinforced Concrete ◽  
Uniaxial Compression ◽  
Crack Formation ◽  
Electrical Response ◽  
Nondestructive Method ◽  
Fibre Reinforced Concrete ◽  
Mechanoelectric Transformations ◽  
Periodic Impulse ◽  
Shock Action

This article presents the results of a study of the effect of crack formation in concrete that occurs during uniaxial compression on the parameters of the electrical response under periodic impulse shock action. Researches were conducted on fibre-reinforced concrete samples and samples without reinforcement. It is shown that the method based on mechanoelectric transformations phenomenon can be equally applied to both unreinforced and fibre-reinforced concrete samples.

Effect of Carbide Content on Temper Embrittlement of 2.25Cr1Mo Steel

2016 ◽  
Author(s):  
Yian Wang ◽  
Guoshan Xie ◽  
Zheng Zhang ◽  
Xiaolong Qian ◽  
Yufeng Zhou ◽  
...  
Keyword(s):  
High Temperature ◽  
Pressure Vessel ◽  
High Stress ◽  
Temper Embrittlement ◽  
Damage Mechanism ◽  
Pressure Vessels ◽  
Nondestructive Method ◽  
Operating Conditions ◽  
Low Alloy Steels ◽  
Carbide Content

Temper embrittlement is a common damage mechanism of pressure vessels in the chemical and petrochemical industry serviced in high temperature, which results in the reduction of roughness due to metallurgical change in some low alloy steels. Pressure vessels that are temper embrittled may be susceptible to brittle fracture under certain operating conditions which cause high stress by thermal gradients, e.g., during start-up and shutdown. 2.25Cr1-Mo steel is widely used to make hydrogenation reactor due to its superior combination of high mechanical strength, good weldability, excellent high temperature hydrogen attack (HTHA) and oxidation-resistance. However, 2.25Cr-1Mo steel is particularly susceptible to temper embrittlement. In this paper, the effect of carbide on temper embrittlement of 2.25Cr-1Mo steel was investigated. Mechanical properties and the ductile-brittle transition temperature (DBTT) of 2.25Cr-1Mo steel were measured by tensile test and impact test. The tests were performed at two positions (base metal and weld metal) and three states (original, step cooling treated and in-service for a hundred thousand hours). The content and distribution of carbides were analyzed by scanning electron microscope (SEM). The content of Cr and Mo elements in carbide was measured by energy dispersive X-ray analysis (EDS). The results showed that the embrittlement could increase the strength and reduce the plasticity. Higher carbide contents appear to be responsible for the higher DBTT. The in-service 2.25Cr-1Mo steel showed the highest DBTT and carbide content, followed by step cooling treated 2.25Cr-1Mo steel, while the as-received 2.25Cr-1Mo steel has the minimum DBTT and carbide content. At the same time, the Cr and Mo contents in carbide increased with the increasing of DBTT. It is well known that the specimen analyzed by SEM is very small in size, sampling SEM specimen is convenient and nondestructive to pressure vessel. Therefore, the relationship between DBTT and the content of carbide offers a feasible nondestructive method for quantitative measuring the temper embrittlement of 2.25Cr-1Mo steel pressure vessel.

scholarly journals Nondestructive Detection of the Gel State of Preserved Eggs Based on Dielectric Impedance

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 394
Author(s):  
Cheng-Han Li ◽  
Chun-Hung Hsieh ◽  
Cheng-Chu Hung ◽  
Ching-Wei Cheng
Keyword(s):  
Decay Rate ◽  
Mechanical Vibration ◽  
Scientific Basis ◽  
Nondestructive Method ◽  
Inspection System ◽  
Nyquist Diagram ◽  
Detection Technology ◽  
The Difference ◽  
The Individual

After completing the production of preserved eggs, traditionally, the degree of gelling is judged by allowing workers to tap the preserved eggs with their fingers and sense the resulting oscillations. The amount of oscillation is used for the quality classification. This traditional method produces varying results owing to the differences in the sensitivity of the individual workers, who are not objective. In this study, dielectric detection technology was used to classify the preserved eggs nondestructively. The impedance in the frequency range of 2–300 kHz was resolved into resistance and reactance, and was plotted on a Nyquist diagram. Next, the diagram curve was fitted in order to obtain the equivalent circuit, and the difference in the compositions of the equivalent circuits corresponding to gelled and non-gelled preserved eggs was analyzed. A preserved egg can be considered an RLC series circuit, and its decay rate is consistent with the decay rate given by mechanical vibration theory. The Nyquist diagrams for the resistance and reactance of preserved eggs clearly showed that the resistance and reactance of gelled and non-gelled eggs were quite different, and the classification of the eggs was performed using Bayesian network (BN). The results showed that a BN classifier with two variables, i.e., resistance and reactance, can be used to classify preserved eggs as gelled or non-gelled, with an accuracy of 81.0% and a kappa value of 0.62. Thus, a BN classifier based on resistance and reactance demonstrates the ability to classify the quality of preserved egg gel. This research provides a nondestructive method for the inspection of the quality of preserved egg gel, and provides a theoretical basis for the development of an automated preserved egg inspection system that can be used as the scientific basis for the determination of the quality of preserved eggs.

Nondestructive Analysis of Dragonfly Eye Beads from the Warring States Period, Excavated from a Chu Tomb at the Shenmingpu Site, Henan Province, China

2013 ◽  
Vol 19 (2) ◽  
pp. 335-343 ◽  
Author(s):  
Yimin Yang ◽  
Lihua Wang ◽  
Shuya Wei ◽  
Guoding Song ◽  
Jonathan Mark Kenoyer ◽  
...  
Keyword(s):  
Inner Core ◽  
Nondestructive Method ◽  
Henan Province ◽  
Manufacturing Technology ◽  
Warring States Period ◽  
Warring States ◽  
Time Period ◽  
Mold Casting ◽  
Warring State Period ◽  
Manufacturing Features

AbstractDragonfly eye beads are considered to be the earliest types of glass objects in China, and in the past have been considered as evidence of culture interaction or trade between West and East Asia. In this article, synchrotron radiation microcomputed tomography and μ-probe energy dispersive X-ray fluorescence were used to determine the chemical composition, microstructure, and manufacturing technology of four dragonfly eye beads, excavated from a Chu tomb at the Shenmingpu site, Henan Province, China, dated stylistically to the Middle and Late Warring State Period (475 bc–221 bc). First, a nondestructive method was used to differentiate the material types including faience (glazed quartz), frit, glazed pottery (clay ceramic), and glass. Three beads were identified as faience and one bead as glazed pottery. The glaze recipe includes quartz, saltpeter, plant ash, and various copper, and is classified as belonging to the K2O-CaO-SiO2 glass system, which indicates that these beads were not imported from the West. Based on computed tomography slices, the manufacturing technology of the faience eye beads appears to include the use of an inner core, molding technology, and the direct application glazing method. These manufacturing features are consistent with the techniques used in China during this same time period for bronze mold-casting, proto-porcelain, and glass.

Analysis of Synthetic Fibers by Diamond Cell and Sapphire Cell Infrared Spectrophotometry

1978 ◽  
Vol 61 (3) ◽  
pp. 526-532
Author(s):  
Leonard K Read ◽  
Robert J Kopec
Keyword(s):  
Sample Preparation ◽  
Analytical Methods ◽  
Nondestructive Method ◽  
Spectrophotometric Analysis ◽  
Infrared Spectrophotometry ◽  
Generic Type ◽  
Synthetic Fibers ◽  
Fiber Sample

Abstract A rapid, simple, and nondestructive method of sample preparation and analysis is described for the infrared spectrophotometric analysis of synthetic fibers. This method uses a combined diamond cell and sapphire cell technique that yields highly resolved spectra with microgramsize fiber samples. From these highly resolved spectra, the generic type of fiber can be readily determined. Although the fiber sample has been physically crushed, it is not destroyed during the analysis and can be further examined by other analytical methods.

FTIR based nondestructive method for metrology of depths in poly silicon-filled trenches

2003 ◽  
Author(s):  
Shoaib H. Zaidi ◽  
George Stojakovic ◽  
Alois Gutmann ◽  
Cornel Bozdog ◽  
Ulrich Mantz ◽  
...  
Keyword(s):  
Nondestructive Method ◽  
Poly Silicon

Realization of Optional Method of Determining the Concrete's Freeze-Thaw Resistance with Help of Dilatometer

2014 ◽  
Vol 1082 ◽  
pp. 258-264
Author(s):  
Olga Pertseva ◽  
Sergey Nikolskiy
Keyword(s):  
Theoretical Analysis ◽  
High Efficiency ◽  
Nondestructive Method ◽  
Labor Input ◽  
Laboratory Equipment ◽  
Freeze Thaw

It’s really necessary to determine freeze-thaw resistance of concrete faster and correctly.The offered method is based on measurement of long strength by nondestructive method, based onacoustic issue. Also dilatometer is used. During this research, the theoretical analysis of concrete'sspecimen dependence on freeze-thaw resistance and energy, which is emitted by a specimen duringdestruction, has been carried out. Freeze-thaw resistance of a specimen is calculated as themathematical relation of these energies. Correctness of the offered method is proved byexperiments. The offered method is characterized by small labor input, high efficiency and a wideapplication scope, but special laboratory equipment is needed.

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