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Pulsed phase thermography (PPT) is a well-established algorithm used for processing thermographic data in frequency domain with the aim to extract information about the defect size and depth. However, few works demonstrated the capability of PPT technique in defects evaluation in real components. The aim of this work is the assessment of capability of PPT technique in determining delaminations in CFRP components used in aeronautics. The component chosen for implementing the technique has a non-uniform geometry and the defects inside it are not simulated, but they are real and generated during the production process. The specimen has been investigated through the application of both the ultrasonic technique and the thermographic one. Thermographic phase images elaborated with a suitable computational processing have been compared with Ultrasonic C-scan images and, the agreement between the location and depth of defects has been verified. Besides, the ultrasonic technique has been used to validate the PPT results.

The identification of defects in real components made in composite material assumes considerable importance in the aeronautical field, as irregularities in the material can compromise its functionality. Also, the possibility (NDT) to verify the effectiveness of repairing on the component during exercise through non-destructive testing techniques has great importance. The goal of the present study is the application of the ultrasound and thermographic techniques for the identification of defects in a repaired component and the evaluation of the damage caused by the application of cyclical fatigue loads. All the important factors were studied, improving ultrasound scanning and allowing evaluating the effectiveness of the techniques used. In this paper, one case of study was proposed for non-destructive damage evaluation employing Phased Array ultrasonic and thermographic methods on aeronautical CFRP component. The structural element analysed is a spar with a double-T section with a hole and presents a repair by scarfing and hot bond process. The experimental results obtained shown the validity of the ultrasonic and thermographic technique for the sensitivity in detecting defects on full-scale aeronautical components with short execution and scan times.

Abstract Capacitor discharge welding (CDW) is analysed to repair aeronautical components made with Inconel 718 and Ti6Al4V alloys, currently used for compressor and turbine applications. The CDW process is a resistance welding technology; it makes use of high-intensity current pulses, discharged by large capacitors. The use of multipoint contact features allows us to reduce stress concentration effects at the weld toe, obtaining thin weld beads, and achieve good material continuity. Base material and as-welded specimens with the same heat treatment were welded, using different parameters, and mechanically tested; the weld bead extension and the microstructural aspect of the welds were finally analysed. The development of advanced technologies for aeronautical components repair is of particular interest and the structural performances at room and working temperatures for capacitor discharge welds have to be carefully studied.

Background Left ventricular (LV) diastolic dysfunction (DD) associated with a preserved ejection fraction (EF) is a frequent alteration in hypertensive patients, usually considered an impairment of the diastolic phase alone. However, because systole and diastole are strictly correlated to one another, it is possible that hypertensive patients with isolated DD may also present with initial abnormalities of LV systolic properties, particularly those presenting with a more severe degree of DD. We performed a multiparametric echocardiographic assessment of LV systolic properties in patients without cardiovascular diseases, with preserved EF and different degrees of DD. Methods We evaluated 1,073 hypertensive subjects showing EF >55% and no overt heart disease. Results A total of 362 patients had normal diastolic function (N), 609 displayed delayed relaxation pattern (DR), and 102 presented a pseudonormal filling pattern (PN). Albeit most of the subjects with DD (DR, PN) had systolic indexes within normal range, they presented a significant reduction of index stroke volume (SV) (P < 0.0001) and stroke work (SW) (P < 0.0001), EF (P < 0.01), midwall shortening (MFS) (P < 0.0001), circumferential end-systolic stress-corrected MFS (cESS-MFS) (P < 0.001), and tissue Doppler (TD) systolic velocity (P < 0.0001) as compared to the N group, particularly the PN group. After adjustments, the reductions of LV systolic indexes were still significantly related to DD, particularly to PN. Conclusions Our results suggest a relation between LV systolic and diastolic properties in patients with normal EF. They also highlight the early onset of a preclinical reduction of systolic properties in patients with “isolated” DD, which is related to the degree of dysfunction.

La Palma island is one of the highest potential risks in the volcanic archipelago of the Canaries and therefore it is important to carry out an in-depth study to define its state of unrest. This has been accomplished through the use of satellite radar observations and an original state-of-the-art interpretation technique. Here we show the detection of the onset of volcanic unrest on La Palma island, most likely decades before a potential eruption. We study its current evolution seeing the spatial and temporal changing nature of activity at this potentially dangerous volcano at unprecedented spatial resolutions and long time scales, providing insights into the dynamic nature of the associated volcanic hazard. The geodetic techniques employed here allow tracking of the fluid migration induced by magma injection at depth and identifying the existence of dislocation sources below Cumbre Vieja volcano which could be associated with a future flank failure. Therefore they should continue being monitored using these and other techniques. The results have implications for the monitoring of steep-sided volcanoes at oceanic islands.