Application Of Acoustic Emission Method Research Articles

Application of acoustic emission method to evaluate the changes in the properties of 17G1S steel after long-term service

Application of acoustic emission method to evaluate the changes in the properties of 17G1S steel after long-term service

Використання методу акустичної емісії для оцінки змін властивостей сталі 17Г1С після тривалої експлуатації

Використання методу акустичної емісії для оцінки змін властивостей сталі 17Г1С після тривалої експлуатації

Application of Acoustic Emission Method to Evaluation for Food Texture

Application of Acoustic Emission Method to Evaluation for Food Texture

Development of accelerated comparative assessment of contact fatigue strength based on the analysis of acoustic emission of friction units

The article presents the results of theoretical and experimental research of acoustic emission of friction units during rolling-sliding friction contact. The purpose of this study is the development of a method of accelerated assessment of contact fatigue strength with the application of acoustic emission during friction contact. The application of acoustic emission method reveals periods of energy state of the material: the activation, the damage accumulation, the transition to the initial fatigue damage. Pulse loading up to the maximum possible value was used for activation of damage accumulation process on the friction surfaces. Specific destructive energy for one load cycle was used as the fatigue strength assessment criterion. The developed technique allows to quantify the fatigue strength in analogy with the methods of such evaluation with the help of fatigue machines for testing at cyclic loads.

Reliability Improvement of Printed Circuit Boards by Designing Methods for Solder Joint Technical Diagnostics with Application of Acoustic Emission Method

The paper represents technical diagnostics of printed circuit boards in particular their solder joints performed by commonly used through-hole and surface mount technologies. Operation and technology cause mechanical interactions and forces between substrate of printed circuit board and electronic components. Such tensile, shear, bending or torque forces transmit through the contact joints, which appear to be the weakest links in the assembly. The experimental research was conducted by mechanical tensile and pure bending tests followed by using method of acoustic emission. Conducted tests demonstrated considerable sensitivity and applicability for the method of acoustic emission to detect defects and possibly to assess the ultimate strength of solder joints in nondestructive diagnostics performed under forces long before the final failure. In order to minimize errors while measuring small loads in tensile tests of ceramic capacitors the special appliance was designed. The experiment was conducted to verify the overheating effect to ultimate load of the solder joints. Surface mount technology for ceramic capacitors has been optimized by introducing high temperature preheating mode that improves adherence to the contact pads and increases tensile strength, what was also confirmed by acoustic emission analysis. The pure bending appliance was designed to provide instant monitoring of all solder joints by equal testing stress. By conducted pulsing test cycles the total count was identified as the most informative parameter of acoustic emission that correlates with types of defects and ultimate strength of the solder joints. The planar location model has been developed by the idea of remote detection of acoustic emission through the volume of homogeneous medium such as water, unlike detecting acoustic emission on the surface of printed circuit board where acoustic emission signal is likely to be distorted or even lost. Using method of acoustic emission and pure bending cycling test the method for technical diagnostics of solder joints has been designed. The results represented in the paper contribute to design and technology improvement in radio-electronics.

APPLICATION OF ACOUSTIC EMISSION (AE) IN MINING AND EARTH SCIENCES: A REVIEW

One of the most important products of the majority of tools, processes and, phenomena in mining engineering and earth sciences are high-frequency elastic waves, often referred to as acoustic waves. These acoustic waves can be a useful tool for prediction and measurement, monitoring and diagnosis. Due to the importance of engineering activities that should be specific, measurable, available, reliable and time-based (SMART), Acoustic Emission (AE) techniques can be inte- grated into engineering operations such as excavation to give exact estimations or simplify some aspects of investiga- tions. Hence, these techniques are expected to play an increasing role in the detection, monitoring, and measurement in engineering applications. With the development of acoustic signal processing methods in earth sciences and the grow- ing need for accurate, fast, and cost-effective prediction, monitoring and measurement methods, AE tools and tech- niques are expected to turn into powerful alternatives to current methods. The purpose of this paper is to review the application of the acoustic methods as a tool in various projects. For this purpose, the application of AE methods has been reviewed in different fields related to earth sciences including mining engineering, drilling engineering, geology, petroleum engineering, and other related fields. According to the purpose of using these methods, the application of AE is divided into three groups: prediction and estimation, monitoring and performance assessment, and detection. The use of AE methods, among other laboratory or in-situ methods, is very fast and accurate, and by only installing specific sen- sors with data logging equipment, it has been able to process and analyse data online and remotely. Finally, the possibil- ity of using AE techniques in design and calculating in various projects and as a tool for decision making was evaluated.

Acoustic emission method for facilitating decision making about the safety of structures being elements of smart cities

Smart City concept is called the concept of the future and it relates to the so-called intelligent cities. Currently, it is the most promising idea aiming at their development, as well as to the development of local economy. Smart City is a response to the changes that have been occurring in the whole world, relating to both expansion and functioning of the cities that become more intelligent every year. Modern agglomerations should use the newest information and communication technologies in such a manner that they increase the interactivity and the effectiveness of urban infrastructure, but also in order to raise the awareness of the residents. Every city that wants to become smart should include numerous aspects connected with urban life in its development plan. One of the factors ensuring the effectiveness of city functioning is Smart Building, which is an intelligent, environmentally friendly construction, and most of all, it is safe for people. Ensuring the safety of the construction requires performing a series of diagnostic operations in all phases of construction object’s life cycle. As the result of the influence of external factors on the structure, including environmental factors, and as the result of useful loads that change during long-time exploitation, the objects are subject to degradation. Early and precise detection of damages that occurred during the use allows to take reasonable measures, including repairs, ensuring uninterrupted exploitation of the object. Therefore, especially in the recent period, a lot of attention has been paid to the topic of diagnostics and monitoring of the structures being exploited, and it is connected with the issue of durability and assurance of reliability of these structures.The article presents the application of acoustic emission methods for monitoring the condition of the construction. Complete usefulness of the AE method applied in monitoring the destructive processes in structures was confirmed, especially that it allows to assess the occurring destructive processes in the conditions of real exploitative loads. It was shown that the presented method is a successful diagnostic tool enabling effective and safe functioning of intelligent city.

Application of Acoustic Emission Method and Impact Echo Method to Structural Rehabilitation

The paper is concerned with the technical aspects of the appraisal and retrofitting process of fire damaged reinforced concrete structures. The assessment of fire damaged structures is carried out along lines similar to those of the appraisal of existing structures. In practice, constructions are most often assessed by destructive tests in-situ and on core bore specimens. In addition to destructive tests, damaged structures are also assessed by non-destructive ones. The present paper shows the use of non-destructive methods of measurement using the acoustic-emission and impact-echo methods. Acoustic emission provides valuable data on the structural integrity of a material. This method has a significant potential to be used for in-situ monitoring and evaluation of the current state of structures. An impact-echo method is based on impact-generated stress waves that propagate through concrete and are reflected by internal flaws and external surfaces. Impact-echo can be used to determine the location and extent of flaws such as crack delamination, voids, honeycombing and deboning in plain, reinforced, and post-tensioned concrete structures. The paper presents a possible rehabilitation plan based on the potential results obtained by these non-destructive methods.

Promising Directions of Application of Acoustic Emission Method in Construction

Promising Directions of Application of Acoustic Emission Method in Construction

Wavelet Analysis of Acoustic Emissions during Tensile Test of Carbon Fibre Reinforced Polymer Composites

The increase of the interest in polymer composites in technology and in people’s everyday lives has been noticed in the recent years. Producing new materials with polymer matrix of particular properties that cannot be achieved by traditional construction materials contributed to high interest in fibre composite materials. However, a wider use of these materials is limited because of the lack of detailed knowledge about their properties and behaviour in various conditions of exposure under load. Mechanical degradation of polymer composites, which is caused by prolonged permanent loads, is connected with the changes of the material structure that are local or that include the whole volume of the element’s body. These changes are in the form of various types of discontinuity, including: deboning, matrix and fibers cracks and delamination. The article presents the example of the application of acoustic emission method based on the analysis of the waves through the use of wavelet analysis for the evaluation of the progress of the destructive processes and the level of the degradation of composite tapes that were subject to tensile testing.

Time-frequency analysis of acoustic emission signals generated by the Glass Fibre Reinforced Polymer Composites during the tensile test

Fibre reinforced polymer composites are currently dominating in the composite materials market. The lack of detailed knowledge about their properties and behaviour in various conditions of exposure under load significantly limits the broad possibilities of application of these materials. Occurring and accumulation of defects in material during the exploitation of the construction lead to the changes of its technical condition. The necessity to control the condition of the composite is therefore justified. For this purpose, non-destructive method of acoustic emission can be applied. This article presents an example of application of acoustic emission method based on time analysis and time-frequency analysis for the evaluation of the progress of the destructive processes and the level of degradation of glass fibre reinforced composite tapes that were subject to tensile testing.

Application of acoustic emission method to study metallic titanium hydrogenation process

The changes occurring in metallic titanium specimens during hydrogenation, that are accompanying by high amplitude acoustic emission signals, have been studied. It was determined that the most probable reason for generation of these signals is crack formation in hydrogenated specimens as a result of internal stresses caused by structural changes in material. Also it was determined that typical sizes of the cracks are comparable with particle sizes of hydrogenated specimens, and the atomic ratio [H]/[Ti] in a solid phase, when crack formation is the most intensive, is generally lower for titanium sponge than for powder made from this sponge, which is explained by a larger specific surface of powder comparatively that of sponge.

Parameters of Acoustic Emission Signals Obtained During the Setting and Hardening of Concrete Mixtures with Different Water-Cement Ratio

Concrete hardening and setting processes are the most critical phases during construction work, influencing the properties of concrete structure. For this reason applying non-destructive testing in the early age of concrete lifetime can be useful. Acoustic emission method is a powerful tool for determination of lifetime concrete structures. Nevertheless, its application in civil engineering area is not easy because many building structures are inhomogeneous. This method can describe material changes during concrete lifetime. Acoustic Emission Method monitors concrete structure continuously. Changes in the whole concrete structure are recorded. The acoustic emission phenomenon is directly associated with nucleation of cracks in building materials, therefore the changes result from the volumetric expansion causing formation micro and macro cracking in structure, which we can recognize. Application of Acoustic Emission Method during concrete hardening and setting with different water-cement ratio will be the aim of this article and his influence on parameters of acoustic emission. A comprehension of microstructure-performance relationships is the key to true understanding of material behaviour.

Applying Method of Acoustic Emission for Monitoring of Different Concrete Mixture during Setting and Hardening

Non Destructive Testing is a powerful tool for determination of properties, durability and lifetime of concrete structures. Acoustic Emission Method is an unusual technique which describes only active defects or changes into structure arising as a consequence dangerous tension into structure. The method is appropriate to be used in homogenous structures as metal structures when cracks are highly active (generates sound). Its application in civil engineering is not so much used because building structures are inhomogeneous. This article shows possible application of Acoustic Emission Method for monitoring of concrete structure changes during its lifetime. The main aim of the article is to show the application of Acoustic Emission Method during the early age to 28 days after mixing. It is believed that early age of concrete structure is very important for its quality. Common concrete cube specimens have been tested after the production by Acoustic Emission Method with using waveguides. The results of acoustic emission method will be compared to classical parameters of fresh concrete e.g. the value water-cement ratio, air void content measured by different methods (pressure methods, AVA) and similar. In the results will be compared four mixtures when two mixtures were aerated and two mixtures were without aeration.

The Design of Electrode for Partial Discharge Location Simulation in Oil Insulated Power Transformer and the Application of AE Method

This paper presents the design of electrode for PD-location simulation in oil insulated power transformer and the application of Acoustic Emission (AE) method. The purpose of this design is to make a simple PD signal simulation and to save the time of experiment. The design must take into account the electric field stress at the electrodes (anode) that will cause PD. The electrodes were designed as 2 types. The first is a conventional electrode expected to make a high nonuniform field. The second electrode was designed as insulation layer and transformer coil to generate higher nonuniform field and expected to cause PD easily. Electrodes were simulated to determine the maximum of electric field by installing in the transformer model. Then, the electrodes are installed in the transformer model to make the real test by supplying high voltage to the electrodes to generate PD signal. From the measurement results of PD-location in the power transformer model according to AE and TDOA method found that, the first electrode has uncertain PD-location measurement results. Moreover, it take so long time of any experiment to obtain PD-signal and sometimes become critical breakdown as a result to damage measurement device. While the PD-location detection results from the second electrode found that it can be easily simulated PD signal. The PD-location result has a better precision or has statistical data to detect PD-location explicitly. Therefore, this special designed electrode could be applied for PD detection study in power transformer or other electrical equipment as well.

The Algorithms of AE Processing for Automated Systems to Measure Rheological

There are the results of the acoustic emission (AE) signals spectrum modification during steel 30XGSA heating near the austenite transformation intervals. It is established in the AE signals spectrum during heating depend on steel phase structure. It makes possible the application of AE method for determination the austenite transformation borders. The critical points of austenite formations and austenite decay are based on heat treatment technologies. It is known, that there are phenomenon of steels properties modification without structure modification not for from phase transformation borders. This was very convenient for detecting the particles with foregone energy characteristics. The automated complex allows one to carry out measurements for a long time using two measuring setups in parallel, which is to study the dynamics of theological and acoustic features of the composition being studied.

Application of acoustic emission method for investigation of hydrogen embrittlement mechanism in the low-carbon steel

The hydrogen embrittlement (HE) phenomenon in the electrolytically charged mild low-carbon steel was investigated during tensile testing coupled with in situ acoustic emission (AE) measurements and post mortem fractographic analysis. It was demonstrated that the ductility reduction correlated with the formation of HE-induced quasi-cleavage regions known as “fisheyes” which formed during the necking stage under the influence of mobile hydrogen. Based on the AE analysis we conclude that formation of “fisheyes” in the mild steel under load cannot be explained by a decohesion mechanism and the alternative mechanisms are discussed.

The Analysis Spectrum of Austenite Transformation on Acoustic Emission Signals

There are the results of the acoustic emission (AE) signals spectrum modification during steel 30XGSA heating near the austenite transformation intervals. It is established in the AE signals spectrum during heating depend on steel phase structure. It makes possible the application of AE method for determination the austenite transformation borders. The critical points of austenite formations and austenite decay are based on heat treatment technologies. It is known, that there are phenomenon of steels properties modification without structure modification not for from phase transformation borders. This was very convenient for detecting the particles with foregone energy characteristics.

Quantification of Micro-Cracks by Acoustic Emission Method during Setting and Hardening of Concrete

As a non-traditional, non-destructive analysis method, the Acoustic Emission Method was used for civil engineering experiment. Concrete is a composite construction material frequently used in civil engineering. We know that concrete is like a man – when concrete is made it is like a baby, then it ages and its properties change in accordance to its baby life. That means it is better to monitor and change its properties when it is young as soon as possible. However, using methods immediately after concrete birth (making the mixture) is difficult. The main aim of the article is to show the application of Acoustic Emission Method during concrete lifetime, particularly during the first days after mixing the mixture. Article describes monitoring concrete structure for 20 days since their making up. Primary interesting part is during first day of hardening. Acoustic Emission Method has used for monitoring both samples. Expected result has been between covered and uncovered specimen.

Study on damage evaluation of bimetal with lead-free copper alloy (Application of Acoustic Emission method)

Study on damage evaluation of bimetal with lead-free copper alloy (Application of Acoustic Emission method)