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Tape automated bonding (TAB) is one technology which is becoming widely adopted for interconnecting integrated circuits to a substrate or package. Both destructive and non‐destructive test methods for evaluation of TAB bonds are analysed and criticised. The key parameters and general guidelines of a destructive beampull test set‐up are identified and presented. The key features of four different non‐destructive test methods are described and discussed. It is found that no universal solution exists for non‐destructive evaluation of TAB bonds although some methods may be more useful than others under certain conditions and constraints. Data and experimental procedure are presented for correlation of scanning laser acoustic microscopy and beampull data.

Around the world, many structures are affected by pathological reactions between the concrete and the surrounding environment in which these structures are designed, these pathologies lead to compromise their serviceability. In this context, this paper aims to study the durability of concrete in different environments with non-destructive techniques, by studying its contamination by the aggressive agents’ penetration. And this, by evaluation of the influence of the durability indicator that is the absorption by immersion, on the mechanical properties (compressive strength, modulus of elasticity and damage), of specimens having undergone immersion/drying cycles, in different aggressive media (water, seawater and acids: sulfuric and acetic with a concentration of 5%).

Concrete specimens were manufactured in the laboratory, and then underwent immersion/drying cycles, in parallel, the weight gain of the specimens was carried out in the wet state after immersion and in the dry state after drying, and the ultrasonic speeds were also taken in a dry state. The results showed a decrease in the mechanical properties studied, namely, the compressive strength as well as the elastic properties (modulus of elasticity, damage) as a function of the increase in absorption, and that the weakest properties are those of test specimens submerged in water.

Non-destructive tests have shown that the parameters examined increase with the immersion/drying cycles, up to the fourth cycle. Beyond that, they drop gradually, and this is valid for four environments. This decline is due to the degradation of cement pastes exposed to water, seawater and acid attacks. This is explained by the greater or lesser dissolution of all the major elements making up the cementitious matrix (CSH, Ca(OH)2, CaO, SiO2, C3S, C2S, C3A, C2S) depending on the nature and concentration of the chemical substances evacuated. The results showed that the highest absorption rate and damage are those recorded for the specimen immersed in water, followed by that of the specimens immersed in acids, followed by that of the specimen immersed in sea water. The highest compressive strength and stiffness are those of the specimen immersed in sea water, followed by that immersed in acids, then in water.

The work developed aimed to study the durability of concrete, by addressing the study of the coupling absorption – mechanical characteristics of concrete, in different aggressive media (water, seawater and acids), to seek a relationship between these parameters. The tests provided are non-destructive tests, which consist of taking measures that do not damage the concrete. They allow indirect measurements of the mechanical properties of concrete as well as the monitoring of their evolution over time. They also allow having certain accuracy, because the measurements are taken at the same place.

This paper aims to report a case study regarding the combined use of several non‐destructive techniques (NDTs) as a tool in the management of diagnosis and refurbishment of a damaged reinforced concrete building.

Four types of NDTs have been selected and carried out on the pillars of the building: visual inspection, electromagnetic rebar location, sonic test and rebound hammer test. The campaign has been planned and run in order to get the highest amount of reliable data about materials degradation and structural safety with limited costs and limited interference with the functionality of the building.

The diagnostic campaign highlighted the usefulness of the selected techniques in the diagnosis of the type and the amount of degradation, thus permitting a plan of refurbishments to be defined, and to get a realistic estimation of restoration costs.

NDTs' ability to specifically identify a type of damage may be viewed as a reliable tool in assessing and managing the structural life‐cycle cost.

The presented case study highlighted that NDTs are very likely to locate and quantify the damage of materials and buildings, so that they can be considered as one of the most important parts of health monitoring of civil structures and infrastructures.

The challenge presented by advanced package development in the past five years has further accentuated the constant need for package quality and reliability monitoring through extensive laboratory testing and evaluation. As pin counts and chip geometries have continued to increase, there has been additional pressure from the military and commercial sectors to improve interconnect designs for packaged chips, including chips directly attached to the printed wiring board (PWB). One of the options employed has been tape automated bonding (TAB). However, this assembly technique also presents new standardisation, qualification and reliability problems. Therefore, at Rome Air Development Center (RADC), there is regular assessment (through in‐house failure analysis studies) of parts destined for military and space systems. In addition, Department of Defense (DoD) high tech development programmes, such as very high speed integrated circuits (VHSIC), have utilised all present screening methods for package evaluation, and have addressed the need for development of more definitive non‐destructive tests. To answer this need, two RADC contractual efforts were awarded on laser thermal and ultrasonic inspection techniques. Through these package evaluations, a number of potential reliability problems are identified and the results provided to the specific contractors for corrective action implementation. Typical problems uncovered are lid material and pin corrosion, damage to external components and adhesion problems between copper leads and polyimide supports, hermeticity failures, high moisture content in sealed packages and particle impact noise detection (PIND) test failures (internal particles). Further tests uncover bond strength failures, bond placement irregularities, voids in die attach material (potential heat dissipation problems), and die surface defects such as scratches and cracks. This presentation will review the specific package level physical test methods that are employed as a means of evaluating reliable package performance. Many of the tests, especially the environmental tests—e.g., salt atmosphere and moisture resistance—provide accelerated forms of anticipated conditions and are therefore applied as destructive tests to assess package quality and reliability in field use. In addition to a manufacturer's compliance with designated qualification procedures, the key to package quality lies in utilising good materials and well‐controlled assembly techniques. This practice, along with effective package screen tests, will ensure reliable operation of very large scale integration (VLSI) devices in severe military and commercial environment applications.

The purpose of this paper is to experimentally investigate the capability of four non-destructive testing (NDT) techniques to detect the layer orientation in textile composite laminates. The aerospace industry has been the primary driving force in the use of textile composites.

Woven glass fiber composite samples were inspected using C-scan ultrasonic, vibration analyzer, X-ray micro-tomography and ultraviolet technique. In a complementary study, mechanical testing was carried out to investigate the effect of mid-layer orientation on in-plane tensile strength and their failure modes using microscopic imagining.

During C-scan ultrasonic, the high attenuation and scattering of ultrasonic waves caused by the textile fabric layers limited its application to only detect the first layer of samples. Frequency response tests of composite samples were also conducted to investigate the effect of mid-layer orientation on dynamic responses. The same trend was observed in the finite element modeling results with a clear effect of the fiber orientation defect seen in frequency response function response and higher mode shapes. Moreover, the results of micro computed tomography demonstrate that this technique could definitely detect the orientation of each layer; however, X-ray imaging at small scales introduced some challenges. Images obtained from ultraviolet technique did not reveal mid-layer orientation.

In this paper, the application of different NDT techniques along with finite element modeling to inspect two-dimensional textile composites was presented. Hopefully, the research results presented here will lead to much published papers in inspection of textile composites.

The purpose of this paper is to describe the approach for the design of a jet engine composite air inlet for a new generation of jet trainer aircraft from the perspective of airworthiness requirements regarding high-speed impact resistance.

Validated numerical simulation was applied to flat test panels. The final design was optimised and verified by validated numerical simulation and verified by testing on a full-scale demonstrator. High-speed camera measurement and non-destructive testing (NDT) results were used for the verification of the numerical models.

The test results of flat test panels confirmed the high durability of the composite structure during inclined high-speed impact with a near-real jet inlet load boundary condition.

Owing to the sensitivity of the composite material on technology production, the results are limited by the material used and the production technology.

The application of flat test panels for the verification and tuning of numerical models allows optimised final design of the air inlet and reduces the risk of structural non-compliance during verification tests.

Numerical models were verified for simulation of the real composite structure based on high-speed camera results and NDT inspection after impact. The proposed numerical model was simplified for application in a real complex design and reduced calculation time.

The purpose of this paper is to focus on the durability of underwater non-dispersible concrete in seawater environment.

In this paper, ten groups of underwater non-dispersible concrete mixtures were designed, and the anti-dispersibility and fluidity of the mixtures were tested.

The durability test analysis shows that different pouring methods have different effects on the durability of concrete. The durability of concrete poured on land is better than that poured in water. Different mineral admixtures have different effects on the durability of concrete: the frost resistance of the underwater non-dispersible concrete specimens with silica fume is the best; the impermeability and chloride ion permeability of the non-dispersible underwater concrete specimens with waterproofing agent are the best; and the alternation of wetting and drying has adverse effects on the durability indexes of the non-dispersible underwater concrete.

The durability of underwater non-dispersible concrete is tested and the results can be used for reference in engineering practice.