Acoustic Emission On-line Monitoring Research Articles

A new acoustic emission on-line monitoring method of laser shock peening

Laser shock peening (LSP) is an advanced surface modification technology that can harden metallic materials by using plasma shock waves. It has significant technical advantages and has important application value in various fields like the aerospace, defense and military. In order to realize the large-scale industrial production of LSP, it is necessary to strengthen on-line monitoring of its working status. Acoustic emission (AE) is a dynamic non-destructive technique to evaluate the material performance change in real-time, which overcomes many shortcomings of traditional non-destructive testing methods and has been successfully applied to on-line monitoring of LSP. Generally the signal and characteristic parameters of AE are affected by sensor position, which is inconvenient to evaluate the quality of LSP in unified standard. The propagation characteristics of AE and the planar positioning function of AE were concerned in this work, the AE energy of material was obtained from detected waveforms and characteristic parameters of AE by calculation, which is helpful to realize the on-line monitoring of LSP.

Design of a Comprehensive Pressure Vessel Experimental Device

The equipment used in stress- and pressure-related non-destructive testing (NDT) experiments tends to have single functionality and a low degree of automation. There are also safety risks inherent in existing pressure testing methods. This paper develops a remote online NDT comprehensive experimental device. It uses a high degree of automation to remotely monitor changes in a pressure vessel’s prefabricated defects during pressure tests. Safety is guaranteed, as the operator is located remotely. The experimental pressure vessel employs a split structure connected by a quick-release system using flange-type U-slot bolt holes. Pressure vessel defects can be prefabricated in different forms, and the vessels can be disassembled and changed easily. This process reduces the experiment materials needed, lowers costs, and saves experimental time. The device can be used for various experiments, such as acoustic emission monitoring of the pressure-bearing and load-holding capacities of pressure vessels, measurement of pressurized vessel strain, and pressure vessel NDT (magnetic powder inspection, ultrasonic flaw detection, magnetic flux leakage testing, magnetic memory testing). Operators can obtain experimental data and conduct analyses simply by controlling the computer. The device can enrich the content of undergraduate experiments and solve the single-functionality problem of existing experimental equipment. With this device, the acoustic emission online monitoring experiment of pressure vessel and the stress measurement of pressure vessel are carried out. Which verify the diversity of function and reliability of the test.

Study on Acoustic Emission Characteristics of Fiber Reinforced Ceramic Matrix Composites

Through acoustic emission on-line monitoring system, the effective value of acoustic emission is measured, which produces in the grinding of fiber reinforced ceramic matrix composites. The mapping relationship, grinding parameters and the effective value of acoustic emission, is discussed qualitatively. And the influence of different grinding directions on the effective value and spectrum also is studied. These could be significant guidance for controlling the grinding process to improve the machining quality.

Use of an on-press acoustic sensor to monitor coldset offset printing of newspaper

A newly developed acoustic emission on-line monitoring technique (Voltaire J. et al. 2004) provides insight into the dynamic interactions occurring between paper, ink-fount emulsion, and rubber b ...

The acoustic emission technique in orthopaedics - a review

Traditionally, orthopaedic research has focused upon the assessment of individual components in an implanted construct. A great deal of research has investigated the durability of the metallic stem, even though this is the most robust component in the implanted system. Standards have been developed for the structural assessment of the implant and even the bone cement which holds the implant in place in the bone. However, the construct as a whole, and its short- and long-term structural integrity, are rarely assessed, and few methods have been established to monitor and predict the mechanisms leading to failure. These are necessary to ensure that any new implants entering the market will perform satisfactorily and prevent premature revision surgery. The acoustic emission (AE) technique offers the capability of monitoring structural degradation passively and in real time, and can distinguish failure mechanisms and their location through the analysis of AE parameters. In the present paper, the use of acoustic emission in orthopaedics, in particular for the evaluation of hip replacement constructs, is reviewed. Following this, three case studies undertaken at the University of Southampton are presented, in which acoustic emission on-line monitoring has been used to evaluate the performance of simulated artificial hip replacement constructs and their constituents during static and fatigue testing. In Case Study 1, the fatigue behaviour of bone cement is characterized; in Case Study 2, the residual stresses induced in the construct as a result of bone cement cure are investigated; in Case Study 3, the mechanisms leading to failure of a carbon fibre reinforced plastic hip stem during fatigue testing are characterized.

Acoustic emission on-line monitoring for petrochemical plants : Zhang,B.Q. Materials Evaluation, Vol. 47, No. 3, pp. 351–355 (Mar. 1989)

Acoustic emission on-line monitoring for petrochemical plants : Zhang,B.Q. Materials Evaluation, Vol. 47, No. 3, pp. 351–355 (Mar. 1989)

Acoustic emission on-line monitoring for high-pressure distributors of natural gas

Acoustic emission on-line monitoring for high-pressure distributors of natural gas