In this paper, a new absolute thermal contrast method is proposed for pulsed infrared thermography.It based on the computations of reconstructed defect-free images so that no priori knowledge sound area sample necessary.Moreover, correction applied to take into account possible delays in acquisition time.Results are presented both Plexiglas TM and graphite-epoxy specimens.Comparisons with Pulsed Phase Thermography phase also along discussion advantages method.

Composite materials are widely used to build structural components, thanks their mechanical properties. Those generally considered 'engineering materials', since they tailored meet specific requirements. Due use for it is important know behaviour, especially under cyclic loads. At present, there a common interest, among researchers, study the behaviour of composites, by means both traditional and innovative techniques, with final purpose making previsions regarding service life. In fact, due...

The urgent need to increase the sustainability of crop production has pushed agricultural sector towards use biostimulants based on natural products. current work aimed determine whether preharvest application two commercial formulations, a Fabaceae enzymatic hydrolysate or blend nitrogen sources including fulvic acids, and lab-made aqueous extracts from Moringa oleifera leaves (MLEs), could improve yield, quality, storability lettuce grown in hydroponic system, as compared an untreated...

Low-velocity impacts represent a critical dynamic condition for engineering structures. Combining two reinforcing fibers in single matrix, i.e., hybridization, is considered feasible way to improve composite performance. In this context, paper presents an experimental work on composites with Kevlar and glass fabrics novel thermoset polyurethane matrix. The coupons are manufactured by vacuum infusion technique low-velocity impact tests carried out. First, the behavior of laminates different...

Moringa oleifera (M. oleifera) is a plant widely used for its beneficial properties both in medical and non-medical fields. Because they produce bioactive metabolites, plants are major resource drug discovery. In this study, two different cultivars of leaves M. (Salento Barletta) were obtained by maceration or microwave-assisted extraction (MAE). We demonstrated that extracts MAE exhibited lower cytotoxic profile compared to those at concentrations ranged from 25 400 µg/mL, on Vero CCL-81...

Lockin thermography with its capability to monitor modulated heat flow in larger areas (several m 2 ) within a few minutes is applied the inspection of aircraft.Using up 6 lamps each power 1 kW, we could inspect subsurface structures (e.g.stringers) and defects (e.g.impact, delaminations) from distance several meters.The method well suited structural integrity aging aircraft near-surface area.By using ultrasonic excitation instead radiation one can display selectively hidden that are...

The advantages of phase sensitive modulation thermography (also called lockin thermography) are here illustrated together with some applications nondestructive evaluation (NDE) on advanced materials and large structures. Lockin has shown to be a versatile tool for rapid inspection surfaces detection defects in where other NDE techniques not able give good results. Besides this, the angle image eliminates many undesired effects like inhomogeneous distribution surface heating that make images...

In this paper the mechanical loss angle heating as an internal thermal wave source is described.Acoustic energy at high frequency (ultrasound) can be coupled into sample.The hysteresis in defect region results increased of defect.When intensity ultrasound modulated a low itself emits frequency.The range large enough for detection surface with lock-in thermography tuned to modulation.This technique combining ultrasonic waves and provides fast imaging imaginary part Young's modulus...

Ultrasound lock in thermography (UL T) is based on thermal wave imaging as a local response to periodical heat deposition.The substantial difference compared photothermal and optical lockin (OL that the source generating provided by defect itself due attenuation of amplitude modulated ultrasound.While friction effects areas with defects selectively, slow modulation provides periodicity heating results emission long ranging waves from defects.This way one has dark field method display various...

The application of thermoelastic stress analysis in composite materials is particularly complicated because the anisotropy material, that determines constant to be dependent on direction fibers. A further difficulty depends constructive stratification whose mechanical properties vary with depth from surface and this causes constants frequency load applied. By using an analytical two layer model, it has been possible interpret experimental data, thus proposing explanation dependence measured...

Design of many aeronautic components takes into account fatigue tests intended to study the component behavior under load and eventually verify their safety before they are put production. Components cyclic loads undergo a periodic temperature fluctuation proportional local principal stress sum (thermoelastic effect). In case adiabatic conditions, which, for material with given thermal diffusivity, achieved frequencies above certain level, measured amplitude oscillating can be used determine...

Double patterning is the best technique which allows 193nm immersion lithography to anticipate 32 nm node, before EUV lithography. The final device pattern formed by two independent steps where dense pitch doubled. This printing each step with higher k1 imaging factor. In this paper we present overlay and CD budget applied a double (DP) for definition of 32nm technology node device, using an scanner tool. A balance among different factors affects necessary optimize alignment performances...

Cold Spray is an innovative technology to create coatings through the impact of metallic particles on substrates. Its application composites’ surfaces recently attracting attention scientific community thanks possibility functionalize and improve their thermal wear properties. Within this context, generation first metal-to-composite layer fundamental. This work presented experimental investigation a composite panel, reinforced with glass fibers coated aluminum particles. The coating was...

Cooling down thermography represents a novel approach to thermal nondestructive testing: the sample is previously heated in an oven order obtain uniform temperature, then it exposed lower ambient temperature. An IR camera monitors surface temperature decay reveal internal defects. While this presents clear disadvantages terms of versatility, allows for faster and deeper penetration sample, has therefore mainly been used deep defects insulating materials.

The method described in this article performs thermal diffusivity measurements on bulk materials using a modulated spot heating of the sample surface and measuring temperature with an infrared detector at different modulation frequencies. Since is single sided it can be performed bulk, does not require preparation sample. Furthermore precise alignment nor movement source detector. measurement unknown requires knowledge shape sensitivity profile surface. This information, difficult to obtain,...

PPT) is presented in this paper.Some theory as well including some comparisons with modulated (or lockin) thermography (MT).

Infrared strip gauges (IRSGs) are strips of metal bonded to the component surface at their ends, with central portion unbonded. A single thermoelastic measurement performed an infrared camera is expected be able precisely read stress indicated by every IRSG, thus allowing for separation in analysis measurements. This paper summarizes results obtained using IRSGs on several materials, experimental campaign aiming evaluating influence different parameters accuracy IRSGs' strain The majority...

While conventional thermographic applications to the human body aim at revealing local temperature changes normally related with beginning of a pathologic process, this paper shows how lockin thermography can be modified in order meet medical needs visualization functionality blood vessels.A compression cuff is used connection system create modulation flow.The amplitude and phase images thus obtained provide infonmation about flow vessels.

Particle boards are very common products in the wood industry. However, increasing use of this product with its derivatives, imposes new challenges terms inspection techniques. Lockin thermography is an attractive tool for such a task. In paper, fundamentals lockin presented followed by several representative examples particle board inspection.

Thermoelastic stress analysis (TSA), performed on metallic components with a high diffusivity coefficient, seldom reaches adiabatic conditions. As consequence, TSA results are affected by an attenuation whose entity varies locally, preventing the use of as reliable quantitative investigation means. The recovery temperature and correct value first invariant, directly linked to it, can only be making assumption local distribution. This article presents method for automatically choosing, among...

The aerospace industry makes large use of aluminum components, which must undergo severe fatigue tests simulating the real loads at they will be subjected. problem is that high thermal diffusivity and low frequency on components can normally performed often prevent achievement adiabatic conditions, attainment quantitative results. Starting study models involving different kinds mono-dimensional stress distributions, temperature attenuation evaluated linked to phase shift. result independent...