Acoustic emission during fracture of ceramic superconducting materials
نویسندگان
چکیده
In the ceramic materials acoustic emission (AE) is associated with a rapid elastic energy release due to the formation and expansion of cracks, which causes generation and propagation of the elastic wave. AE pulses measurement allows monitoring of internal stresses changes and the development of macroand micro-cracks in ceramic materials, and that in turn allows us to evaluate the time to failure of the object. In presented work the acoustic signals generated during cracking of superconducting ceramics were recorded. Results obtained were compared with other ceramic materials tested the same way. An analysis of the signals was carried out. The characteristics of the AE before destruction of the sample were determined, that allow the assessment of the condition of the material during operation and its expected lifetime.
منابع مشابه
Acoustic emission from BiSrCaCuO superconducting samples
The aim of the paper was to show if the acoustic emission (AE) signals from BiSrCaCuO ceramic superconductors appear during normal state–superconductivity transition. These AE signals were previously observed from YBaCuOtype superconducting materials. The BiSrCaCuO samples were prepared and characterised. The resistance–temperature and current–voltage characteristics of these samples were measu...
متن کاملDamage Energy Evaluation in [55/-55]9 Composite Pipes using Acoustic Emission Method
In this study, the longitudinal and hoop tensile strengths of an industrial ±55° Glass Reinforced Epoxy (GRE) pipe with eighteen layers as well as the associated failure mechanisms are determined. To obtain the longitudinal and hoop tensile strengths values, three specimens are cut from the studied GRE pipe in each direction. A comparison is done between both the strength values, and the fractu...
متن کاملAcoustic Emission in Materials Research – a Review
This paper reviews progress in methods of signal analysis used in acoustic emission (AE) as applied to materials research field. The achievement and inadequacy in understanding of AE from materials during the deformation, fracture and other processes are examined systematically. New goals for the future are also discussed in view of new analytical tools and vastly advanced instrumentation.
متن کاملNondestructive Damage Evaluation in Ceramic Matrix Composites for Aerospace Applications
Infrared thermography (IRT) and acoustic emission (AE) are the two major nondestructive methodologies for evaluating damage in ceramic matrix composites (CMCs) for aerospace applications. The two techniques are applied herein to assess and monitor damage formation and evolution in a SiC-fiber reinforced CMC loaded under cyclic and fatigue loading. The paper explains how IRT and AE can be used f...
متن کاملEvaluation of in situ fracture toughness of ceramic coatings at elevated temperature by AE inverse analysis
This paper describes acoustic emission (AE) measurement at elevated temperature by laser techniques. AE signals originated from microfracture of Al2O3/SUS304 plasma sprayed coatings were detected using a laser interferometer during thermal cycling. The radii of microcracks were evaluated by the inverse analysis of AE signals. Microcrack radii were also studied by the numerical analysis based on...
متن کامل