Qualification and Diagnosis of Carbon and Glass Fibre-Reinforced Composites with Non-Destructive Measurement Technologies

Final Report Summary - QUALIFIBRE (Qualification and Diagnosis of Carbon and Glass Fibre-Reinforced Composites with Non-Destructive Measurement Technologies)

Executive Summary:
Today, fibre-reinforced composites (CRP/GRP) can be found in high tech applications like in aerospace and energy industry. The production of these materials is expensive and the quality control is often manually conducted. As the processes of quality control and even the way how to analyse and characterize damage and defects within fibre-reinforced composites are not standardized yet, parts consisting of these materials are replaced instead of being repaired, often without being sure, whether the function of the part is negatively affected or not. It can be easily imagined, that high costs occur by this approach.
In the future fibre-reinforced composites will be increasingly used in every industrial sector, in which material characteristics like light weight in combination with high resistance is required. Especially automotive industry is now focusing on these new materials, looking for innovative application areas e.g. trim parts without additional finishing. For this purpose manufacturing processes and material costs have to be developed in a comparable range of today’s costs.
The project QualiFibre examined the possible ways for an adequate quality assurance for CFP- or
GRP-components. To receive calculable quality, measurement methods and data processing procedures are necessary. Considering different aspects of CRP/GRP-products it is obvious, that only non-destructive technologies like 3D-computer tomography, thermography and ultrasonic scanning in correlation with intelligent software solutions will lead to significant and evaluable results.
The overall aim was to achieve a comparable and measurable quality standard for CRP/GRP products. This will prepare applied CRP/GRP products to enter large-scale markets and new industries. The project results and the gathered knowledge allow the SME partners to expand their portfolio. This will improve their competitive position in the global market.

Project Context and Objectives:
Originally composite materials have been developed by aerospace industry as an alternative to metallic materials because they are lightweight and temperature-stable. In the meantime it appears clearly, that fibre-reinforced composites with tailor-made characteristics do have a much more diversified application spectrum. In industry there is a great demand for safe and resistant lightweight construction materials, e.g. in energy and drive technology as well as in mass markets like automotive industry. Modern temperature-stable fibre-reinforced composites like high temperature heat exchangers, ultra-light and wear-resistant friction linings and brakes can be manufactured. Consequently it is foreseeable, that the production of composite materials will turn out to become a key technology. However manufacturing costs for fibre-reinforced composites are high.
Therefore quality assurance plays a decisive role, especially when concerning relevant to security products.
The proposed project will examine the possible ways for an adequate quality assurance for carbon-fibre-reinforced plastic (CRP) or glass-fibre-reinforced plastic (GRP) components. To receive calculable quality, measurement methods and data processing procedures are necessary. Considering different aspects of CRP/GRP-products it is obvious that only non-destructive technologies will lead to significant and evaluable results. First of all most CRP/GRP productions are still not automated. Therefore the quality from one part to another can differ extremely and the only method to get comparable data of a quality analysis is to measure the same part non-destructively. Moreover the high costs of CRP/GRP products motivate to reduce waste. Additionally, the most important reason is that defects and material parameters, which will have an effect on the subsequent application, can occur in different steps in a CRP/GRP lifetime:
• in production material inclusions, dry patches or other faults can happen without notice
• the finished part can have problems, e.g. high porosity or delamination
• CRP/GRP products in use or/and on-load can develop delamination, impact damages or signs of material fatigue.
Finally CRP/GRP products, which are damaged and shows malfunction, normally become waste.
However a quality and behaviour estimation will make a repair procedure possible. Repair instructions and their impact will be quantifiable and evaluable which will lead to cost optimisation especially considering high class and high security products.
To realise an optimal quality assurance, it should be possible to inspect the same CRP/GRP product at every step and any time. For the different parts and types of errors, different non-destructive technologies are qualified or adaptable. So 3D-Computer tomography (CT), X-ray dark field imaging, thermography and ultrasound have been identified as suitable technologies with different advantages. By using CT technology it is possible to reconstruct whole parts with all inner structures and geometries as well as with high resolution, whereas thermographic and ultrasonic system are portable technologies and offer fast data acquisition. To cover all needs of an effective quality analysis, it will be necessary to combine different sensor technologies and to use high resolution data to qualify the two faster technologies. Moreover intelligent software solutions for data processing will be necessary to evaluate CRP/GRP-images or 3D volumes and to fuse data acquired from different sensor systems.
For this reason the scientific objectives of this project were
• characterisation of CRP/GRP material and quality parameters and application behaviour
• qualification of non-destructive technologies for the different CRP/GRP material and quality parameters
• combination of non-destructive technologies to multi-sensor systems and to technology comprehensive data evaluation
• development of a software system for data fusion, visualisation and processing of the different non-destructive technologies.

The main goal was to achieve a comparable and measurable quality for CRP/GRP products.
This will prepare the entry of applied CRP/GRP products to large-scale markets and new industries.

Project Results:
In the following section an overview of the results achieved in the QualiFibre project is given. The project examined the feasibility of various NDT technologies and their combination for an adequate quality assurance for FRP (fibre reinforced plastic) parts, focusing on glass and carbon fibre and epoxy resins.
Common to most FRP parts is that they tend to “hide” their true damage status. While a metal part e. g. will show a dent after an impact, the damage after impact of a FRP will mostly be invisible at the part surface.
Considering different aspects of FRP-products it is obvious that only non-destructive technologies can lead to significant and evaluable results. Two main technological categories have to be distinguished: portable and fixed sensing technologies. Fixed can’t be used on-site (or only with a strong logistic) as X-rays Computed Tomography and Dark Field Imaging because of complexity and radiations. In the opposite, Thermography and Ultrasonic could be used on-site without any limitations.
The project takes into account this large variety of solutions to be able to give an answer to most of the situations industry can meet today. Each of these approaches could be employed in factories or for FRP end-users. Especially as the production methods for FRP parts are still not fully automated, the quality from one part to another can differ strongly and the only method to get comparable data for quality assessment thus is to measure the produced parts non-destructively. Additionally most high FRP parts are complex in shape and function and produced at high costs, so there is a strong motivation to avoid unnecessary loss of material.
Defects affecting the various applications can occur in different steps in a FRP lifetime:
• During the production material inclusions, dry patches or other faults can happen without notice.
• The finished part can have lot of problems, like for example high porosity or delamination.
• CRP/GRP products in use or/and on-load can develop delamination, impact damages or signs of material fatigue.
Eventually, when a FRP product is damaged and shows malfunction, it will normally be scraped. A reliable and easy to use quality and behaviour estimation will make a repair procedure possible. Repair instructions and their impact become quantifiable and evaluable, with calculable quality parameters.
Measurement Methods
In this project only non-destructive examination methods are used. This has the advantage that the examined parts are not affected and can be used even after the examination. Also the examination under non destroyed circumstances ensures that all properties of the part can be expected. In destructive testing it can occur that the property, which should be analysed, is destroyed. Another benefit of non-destructive testing is its repeatability. The following non-destructive testing methods are used: ultrasound, thermography, computer tomography (CT) and dark-field imaging. They are outlined in the following section.
Computed Tomography
Computed tomography is an imaging method based on X-ray absorption which allows three-dimensional volume imaging of an object. The object is radiographed from a number of different directions. With the aid of computer algorithms, a cross section of the object can be reconstructed from this set of measured radiographic projections. Conventionally a circular orbit is realized by either rotating the object or the X-ray source and detector around the object.
Industrial Computed Tomography (CT) is a well-established tool, primarily in automotive, aviation and aerospace industry. The X-ray energy limits the maximum object thickness for a given material. Within the latest generation of CT systems the tube voltage has been raised to 600 kV. To improve the image quality and allow for measuring long objects helical orbits were used in which the object is not only rotated but also shifted in longitudinal direction.
Large two-dimensional objects like plates, boards or other layered structures prevent 360° orbits. Additionally, the X-ray attenuation depends strongly on the incident angle. To overcome these limitations transversal-CT uses a source and detector that move in opposite directions parallel to the object surface while continuously focusing a certain region of interest (ROI).
X-ray dark field imaging
Conventional X-ray imaging detects changes in the density or composition of materials based on the attenuation of X-rays passing through the sample. However, X-rays are also refracted resulting in minute changes of the ray path. The interaction of X-rays with matter can be described by a complex refractive index . Conventional X-ray imaging is sensitive to the imaginary part β which describes the attenuation of the X-rays; differential phase contrast imaging (DPCI) allows measuring the scattering of X-rays in a sample, described by δ, by using a Talbot-Lau interferometer. The rays from an X-ray tube pass through the source grid G0, which creates several beams. When passing through the phase grid G1 each of these beams is split into two coherent beams that travel under slightly different angles. At given distances an interference pattern is created. Since this interference pattern cannot be resolved with a typical X-ray detector, an absorbing analyser grid G2 with a period adapted to the period of the interference pattern is inserted.
Changing the lateral position of either the phase grid or the analyser grid perpendicular to both the X-ray beam and the grid lines changes the phase of the interference pattern. From a set of recorded images the amplitude, phase and mean value of the interference pattern are calculated. The mean value corresponds to the conventional attenuation signal, the phase change of the pattern is proportional to the refraction of the X-ray beam, and the amplitude is a measure of the spatial coherence of the beam. The latter is called the dark-field signal. The dark-field signal is very sensitive to small voids in a test sample, since the spatial coherence is reduced by scattering.
In theory, a micro-focus X-ray tube has a sufficient spatial coherence that the source grid G0 is not needed. The existing micro computed tomography setup at EMPA was upgraded with the two grids G1 and G2 to allow for differential phase contrast imaging.
Thermography
Thermography uses an infrared (IR) camera to record the spatial and temporal variation of the surface temperature of the inspected object. Active thermography is based on the measurement of a heat flow artificially generated in the object. A defect perturbs the heat flow, which can be detected on the sample surface over time. The technique is rather easy to apply to most materials, and sensitive to a depth of up to 10 mm.
Lock-in thermography is based on thermal waves generated by sinusoidal excitation at a frequency f, which introduces thermal waves that diffuse into the test specimen. The lower the frequency the deeper is the penetration depth. From recording an IR image sequence during the heating cycle, information about the phase and magnitude of the reflected thermal wave is derived. The phase angle images are less sensitive to local variations of illumination and surface emissivity over the sample and have a better signal quality from higher depths compared to the magnitude images. In order to get good resolution for various defects at different depths inside the test specimen, it is necessary to repeat lock-in measurements at different excitation frequencies.
A lamp excited lock-in thermography concept was implemented in the system and has proved to be a method that allows larger CFRP / FRP parts to be investigated for defects, such as breakage, delamination and cracks, in a shorter time.
Ultrasound
Ultrasound testing uses a piezo transducer to launch ultrasound waves into an object, and a transducer to measure the surface vibration in transmission or reflection. To obtain an image of the object, the transducer(s) must be scanned across the surface. Conventionally, efficient coupling of the transducer to the object is realized by immersion into water or by using coupling fluids. This is not viable with composite surfaces that are compromised when in contact with coupling fluids, or when handling must be simplified as for in-line testing. Coupling through air has been investigated, because the transducer is not in contact with the object. However, air-coupling system work best with low frequencies which reduces the resolution of ultrasound signals. This necessitated the development of more sophisticated signal processing algorithms. The ultrasonic system developed by Sonotec is composed of a mechanical system with transducers working in transmission, coupled to a computer / professional software to register ultrasound data.

Defined defects
There are multiple mechanisms that can lead to a structural failure of a FRP part:
a) the fibres can break,
b) the matrix can break and
c) fibres and matrix can lose contact (adhesion).
All these mechanisms lead to deteriorating functionality up to the complete failure of a single part or technical structure.
The factors that lead to the above mentioned failures can be
a) overload beyond the foreseen mechanical loads or
b) weakening of the material leading to a local or general overload situation even before reaching the load level foreseen as critical in the design of the part.
The main components of FRM (fibres and matrix) can be damaged or even destroyed by mechanical loads, chemical processes, radiation as well as temperature (high or low) or abrasion / erosion.
The different sections of the life cycle of a part (production, shipping, use) are characterised by specific risks and lead to specific damage patterns. Today the production of high performance and highly functional carbon and / or glass reinforced plastic (CRP / GRP) material products, like in aerospace industry, is realised in rather small series and often with multiple manual steps.
Therefore significant fluctuations within the output quality often have to be accepted or lead to degraded material and high production costs. The problem is, that the effects of different defect structures cannot be reliably estimated, so that the manufacturer can decide whether the product still can be used or not. Another problem is, that if CRP / GRP material products are in use and get damaged during their lifetime, no repairing procedures are defined and even more: no analysis and classification tools are available for the workshops.
In consequence defects in FRP parts have been classified into different categories based on their structural characteristics and whether they have been caused already during the production of the part or are a consequence of damage during the parts use (e. g. overload or impact).
Defects occurring in the production process can be
a) incorrect fibre volume content (not enough matrix material and in extreme cases the so called “dry patches”, too much matrix materials up to the total absence of fibres) and
b) fibre orientation errors (local errors, e. g. undulated fibres, layup errors or fibre displacements due to the filling process).
c) Matrix mixing errors (e. g. insufficient mixing of the resin and curing agent, wrong mixing ratio, porosities / bubbles due to the mixing process, rheodestruction (mixing / pumping the matrix after gel time resulting in irreversible weakening of the mechanical properties of the matrix),
d) insufficient curing temperature, overtemperature,
e) none or insufficient adhesion of fibres and matrix (e. g. wrong fibre coating / activation, fibre contamination)
f) mechanical damage during demoulding or post cure handling and
g) deformations due to improper support before and / or during the curing process or due to internal stress.
Each testing module of the prototype instrument was qualified for characterizing the various types of defect. It was also investigated which defects are expected at a given state in the product cycle. Based on this a “FRP defect structure qualification and characterization method matrix” was created.
The defects typical for the production process have been introduced in the production of the test parts e. g. by intentionally inserting additional fibre layers (to produce dry spots) or by contaminating the part before infiltration with particles (e. g. wood chips) or release agent (to simulate delamination).
Test parts
The geometry of the test parts has been kept simple to support assessment of the defects and efficient part handling. As the vast majority of FRP parts are plate-shaped and with moderate curvature this approach was considered appropriate for the project activities. The standard test part geometry was chosen following DIN 65561.
A mould suitable for the production of the flat sample parts for impact testing and other tests has been produced in two copies to be able to manufacture the amount of test parts needed. The parts were produced using the RTM-process, which is characterised by injecting the resin under pressure in a closed mould, thus delivering parts with defined wall thickness and good surface quality with good repeatability.
The upper cover of the mould was made of transparent material to allow the close monitoring of the infusion process.
Reference parts (no defects) as well as test parts with definitely produced defects have been made available. The defects produced cover the possible problems during manufacturing, e. g. contamination of the fibre layers resulting in poor bonding of fibres and resin and impact damages introduced with a drop weight test.
Inserted holes and optical reference marks helped superimposing of the measuring results of the various measuring principles (data fusion).
Data Processing and Evaluation
To analyse the data achieved by the different non-destructive examination methods advanced, intelligent and automated 2D and 3D data analysis algorithms are necessary. The different kinds of data sets have to be visualised and compared. For this purpose a non-destructive testing (NDT) machine vision platform has been developed.
Data Sources
The different measurement technologies used for data acquisition deliver different kind of data output. Thermography, ultrasound and dark-field produce 2D data, in contrast to CT which generates 3D volume data. These data sets have to be visualised and automatically analysed.
Visualisation
The developed NDT Machine Vision Platform enables the visualisation of 2D and 3D data. The visualisation of 2D data is a single image, while the visualisation of the 3D data consists of three image stacks. These image stacks show slices through the volume in different views (xy, xz, yz). These slices can be scrolled to see the inner parts of the examined work piece.
Data Processing Methods
For the evaluation of the data sets different advanced and automatic analysis algorithms are used which are integrated in the NDT Machine Vision Platform.
2D Data Processing
For the defect detection in images from thermography and ultrasound respectively, an algorithm chain was developed. The main challenges were the denoising of the input data and the segmentation of the defects independently from the brightness level. Using the developed chain of algorithms with appropriate parameters defects like inclusions, delaminations or dry spots can be detected in thermography data as well as in ultrasound data.
After defect detection several geometric properties as area, perimeter, minimum and maximum extent of the defects are measured. Based on these properties a classification and assessment of the defect can be made. The results are shown in the graphical user interface as well as stored as part of the report.
3D Data Processing
Mainly three analysis algorithms are included for 3D data evaluation in the NDT platform: porosity, defect and fibre orientation analysis. All algorithms have been developed in-house and adapted to the inspection task.
After selecting the right parameter settings, the porosity analysis find automatically all pores in the data set and offers furthermore statistical information about e. g. the density and volume of the pores.
Other defect types like e. g. cracks, inclusions or delaminations can’t be found by the porosity analysis. For this task a 3D texture based defect detection algorithm is used. The defects are automatically recognised and marked by a colour value according to the magnitude of the failure in the CT data file.

The third available algorithm for the evaluation of 3D volume date is the analysis of fibre orientation. The fibre orientation has a strong effect on the stiffness and stability of FRP parts. The algorithm is able to detect the fibre orientation automatically and marks all fibres with the same orientation in the same colour.
Fusion of the Data Sets
The images from ultrasound and thermography can be fused by the NDT Machine Vision platform. The fusion is performed on feature level, which is the most appropriate fusion level for the different data sources. In this case the probability that a defect is present is calculated for every pixel of the input images. In the fusion step these probabilities are combined. The method of the fusion process is pixel based average.
For now no directly fusion of 3D and 2D data is implemented, but the NDT-Platform offers the user the visualisation of both data types at the same time and in the same program, so that he can easily compare them.
Added Value of the Fusion
Some of the defects can be detected by thermography only while others can be detected by ultrasound only. The fusion allows the detection of all defects that can be recognized by at least one technology. Furthermore the fusion allows the detection of defects that are rejected in the separate evaluation of both data sets due to small probability. Here’s assumed the combined probability is high enough for detection.
The visualisation of the 3D CT data and the 2D thermographic/ultrasonic data at the same time and in the same program makes it easier for the user to take advantage of the detailed information offered by the CT technology. So he can easily interpret what is visible in the 2D data sets. In this way the 3D CT data can be used as reference for 2D data without much effort, which makes the 2D data evaluation results more reliable.

Repair Procedures
“No car workshop is prepared for carbon.
A repair concept is still unknown by today.”
Prof. Herbert Kohler, Vice President Group Research & Sustainability
Source: Südwest Presse, 2013-04-18 “Wunderstoff mit Macken”
Following this, repairing a FRP part is still considered to be a challenge when looking towards growing lot sizes and a wider range of application.
The sensor and data fusion oriented approach of QualiFibre allows a much better identification and isolation of the defective / damaged zones of a part. This allows a much more precise definition of the minimal repair zone to be worked on to restorer the full usability of a FRP part.
The final result of the sensor- and software-based assessment must be a clear picture of localization and extent of damaged material.
This is the basis for the decision, where and how much material has to be considered as damaged and has to be removed. The repair will be performed in the following steps:
• structural stabilisation,
• damage removal and
• restoration of structural integrity.
Removal of the damaged portions
Dent pulling is no option for fibre reinforced materials due to their in-existent plasticity. The damaged material has to be removed completely. Especially for bigger structures the damage will produce deformations and misalignments. To ensure the safety of the structure and the feasibility of the repair the structure has to be stabilised with external means. This will ensure the correct position and orientation of the overall structure as well.
The removal of damaged portions must consider neighbouring structures (other parts, coatings, cables, pipes etc.) and the overall alignment of the structure. This removal is performed by grinding, milling, laser ablation (the latter is still a matter of ongoing research). To allow the restoration of the full load bearing capability the material removal must be performed in a flat angle to the direction of the main force – the so called shafting - to ensure mainly undamaged / unrepaired fibres in any chosen cross section.
The classical repair approach is, to remove the damaged section – in most cases significantly more than the really damaged material – by manual grinding. This approach has been used for the repair of a subset of the test parts. Disadvantage of this approach as of all manually based procedures is the dependency on the skills of the workers and thus a rather reduced repeatability and a rather irregular shape.
An approach with significantly better repeatability is the removal of the damaged material through a milling operation using a CNC milling device. This can be a classical milling machine or a portable device. The latter has to be fixed and aligned to the structure to be repaired.
Insertion of material patches to restore load bearing capability
The commonly used approach is the wet laminating to replace the damaged portions with an adequate amount of fibres with the original orientation. This again manually performed step needs highly experienced and skilled workers. The surface normally needs additional grinding to restore the initial shape and surface.
An approach with much better repeatability is the production of a milled replacement patch and gluing it into place.
The test parts with and without defects and before and after repair have been tested in a compression after impact test (CAI) to assess the effectiveness of the repair.

Conclusion
Assessment of measuring methods
Transversal CT leads to clear cross sectional slices. However, an increasing distance to the focal point manifests in defocused and blurred images.
The micro CT dark-field imaging setup turned out to be inefficient, so that it was decided to stick with a quasi-parallel setup with a macro focus X-ray tube in the Talbot-Lau interferometer configuration.
Thermography is the most promising technology for inline NDT not least through the significant price drop of infrared cameras. Lock-in thermography suppresses the sensitivity variations within the detector array and the properties of the sample and has a high signal-to-noise ratio. The lock-in thermography concept implemented in the developed system allows larger CFRP / FRP parts to be investigated for defects in a shorter time. Defects’ depth information can be obtained during the testing process through variation of the excitation frequency. Nevertheless, thermography is only capable of testing surface-near structures for flaws.
Ultrasound testing has been successful for finding matrix cracks, fibre-matrix debonding, fibre breakage and delamination. Ultrasound technologies possess a great potential for testing composite materials and has been used in production lines. Despite of its value, non-contact, air-coupled ultrasound testing (ACUT) is still ambitious and demanding to transfer to robust industrial testing. The most important drawback is the loss of intensity compared to conventional ultrasound which is caused by the coupling inefficiency between the material surface and air. Besides, the experimental technique developed for contact techniques, cannot be directly applied for ACUT. Due to the low signal-to-noise-ratio between incident and transmitted power levels air-coupled ultrasound remains commonly only practical in transmission technique.
Software prototype for data processing
The possibility to visualize and evaluate data from thermography, ultrasound, darkfield and CT in one modular software platform (the NDT machine vision platform) and merge results coming from thermography and ultrasound and compare them with other kinds of NDT results for example from CT offers a real added-value instead of just having some technical reports the technicians have to mentally superimpose. The concerned people will increase their confidence level in defect detection by comparing data from different sources.
By considering the time saved by avoiding long meetings and discussions about defects’ sizes, reparability and so on, it’s reasonable to consider that the benefits of such capacities will allow saving a lot of outgoings.
Repair concept
The assessed measuring methods bring the advantage of having a much more precise knowledge on shape and extent of the defect in the FRP structure.
Based on this knowledge the removal zone for the damaged material can have minimal extent. This is valid for all subsequently applied repair procedures.
The repair concept comprises in the following steps:
• structural stabilisation,
• damage removal and
• restoration of structural integrity.
The removal can be performed either classically by manual grinding or through CNC milling of the shafting contour.
The removed material is than replaced by manual wet laminating or by the insertion / gluing of a previously milled repair patch.

Potential Impact:
The project’s aim was to strengthen and improve the competitiveness of the SMEs in their countries and also at European and international level. This is especially achieved by opening new market perspectives or expanding the existing market penetration with new and innovative inspection solutions and quality standards for inline quality inspection, maintenance and repair of carbon- and glass-fibre-reinforced plastic components (CRP/GRP components). The industrial use of carbon- and glass-fibre composites has increased in different production fields within the last years and will reach double-digit growth rates within the next years, especially in Europe. Originally composite materials have been developed by aerospace industry to offer an alternative to metallic materials, which is low weight and particularly temperature-stable. In the meantime it appears clearly, that fibre-reinforced composites with tailor-made characteristics do have a much more diversified application spectrum.
In industry there is a great demand for safe and resistant lightweight construction materials. Beside aerospace industry the main industrial sectors, which use more and more parts of carbon or glass fibre reinforced plastics are the energy sector (especially wind energy) as
well as mass markets like the automotive industry. Today modern temperature-stable fibre-reinforced composites (e.g. more effective high temperature heat exchangers, ultra-light and wear-resistant friction linings and brakes) can be manufactured. In the automotive sector the
advantages of lightweight construction are now clearly seen in order to reduce the car’s weight and save fuel. This technology is already categorized as a key technology for future automotive production.
Fibre-reinforced composites are on the one hand lightweight and flexible, on the other Hand temperature-stable and have a high load capacity. Nowadays they are mainly used in smallseries production. In order to enable their application in mass production the qualification of inspection processes is essential. Since manufacturing costs for fibre-reinforced composites are high, quality control plays a decisive role, especially as far as security relevant products are concerned. Therefore a complete non-destructive material characterization and defect analysis in adequate time and also with appropriate effort is necessary. This meets exactly the main goal of the project.

For further exploitation the results of the development work are very important concerning the characterisation of composite materials and components in order to guarantee the applied quality. During the application of CRP to lightweight structures of coachwork supporting elements many different defect classes are necessary. Here porosities, delaminations, bonding flaws, fibre fractures as well as inclusions of extraneous materials are to mention, which have to be reliably detected during an inspection. Without these inspection results the series production of CRP/GRP components will not be achieved at reasonable costs and quality.
The advantages for European industry, especially for the SMEs, are given in many ways. First of all the particular sensor system manufacturers involved in the project will be able to open up new applications for their products and to expand their offer and expertise. Especially by integrating and using the developed NDT Machine Vision Platform together with their sensor systems new applications in inspection and quality control for CRP/GRP parts become available. The range of inspection services will also be enlarged, especially for CT-Services because of the costs of CT systems. CT-service providers, like the SME partner Tomo Adour, benefit from this development around hardware and software.
Moreover CRP/GRP producers which are often SMEs profit by using the developed inspection technology. They will be able to offer their customers comparable quality standards, cost optimized and reliable processes which are the key to large scale market and new industrial branches.
The aerospace industry is still the largest CRP application field in the world. However the application of CRP/GRP parts and components in wind energy and automotive industry are growing rapidly especially as far as Europe is concerned. The automotive industry and its suppliers are an extremely important branch of industry in Europe. It plays a key role for the economic situation and employment. In future this sector
will only be competitive on the world market with innovate solutions for saving fuel, reducing the emission of carbon dioxide and electric drives. Here CRP/GRP components can make a large and important contribution. Lightweight construction is already regarded as a key technology for the automotive sector. Inline-Inspection solutions as well as maintenance and repair of CRP/GRP components are therefore of great importance for the automotive industry.
Renewable energy gets more and more important for Europe, especially with regard to increasing shortage of resources and climatic changes. By growing use of alternative methods for energy generation like for example use of wind energy plants this sector has a large potential for exploitation. For example for rotor blade design CRP/GRP components are used which have high quality requirements.
Even in the fields of leisure time and sport, fibre-reinforced composites become more and more important. For example there are also manufacturers of bicycle frames who are strongly dependent on quality inspection during manufacturing. Another sector is medical
engineering. Here CRP/GRP is used for prostheses and orthoses. Especially for CT inspection solutions this is also a relevant market segment.
All involved SME partners have good contacts to industrial end users from automotive industry (for example AUDI or Daimler), aerospace industry (for example Airbus or Eurocopter) as well as from energy sector.
The industries’ high interest in inspection technology for CRP/GRP parts is not only recognisable with regard to the manufacturing process and quality inspection of the produced part, but also concerns the usage and maintenance of the built-in parts. Moreover repair procedures are in the focus of the end users because the CRF/GRF parts are still very expensive due to high manufacturing costs.

The most important dissemination goals that should be reached by the consortium are:
• Creation and development of a durable cooperation model between research and industry allowing a coherent and flexible knowledge transfer from both parts.
• Knowledge transfer to an increased number of SMEs, companies, universities and research centres both from EU and PAC members.
• High efficiency of the dissemination expressed by the number of the target group members (from the quantitative point of view) and by the innovative degree of the knowledge generated in the project (from the qualitative point of view).
In order to achieve these aims, different strategies have been pursued. First the consortium has spread the new technology and knowledge by publishing contributions and organizing events.
All partners have presented the new technologies at national and international trade fairs that addressed directly potential end users. So the interest of future customers has been sparked in the achieved project results and direct industrial contacts have been made. Therefore the partners have participated in at least 5 fairs either alone in agreement of all or together.
Besides, relevant industrial associations and user groups, including management oriented organisations have been contacted and involved in the dissemination activities. Among others, these are the following industrial associations:
• Carbon Composites e.V. (Germany),
• AVK Industrievereinigung Verstärkte Kunststoffe (Germany),
• DGZfP (Germany),
• VDMA (Germany).
Ultimately, in order to reach the public thoroughly and to guarantee an efficient exchange of project results, requests, etc. a project web site has been implemented which is accessible since end of January 2013. On the web site visitors find an adequate presentation of the project’s aim and contents as well as dissemination activities and publishable results in accordance with the project’s progress.

The first period of the QualiFibre project was mainly affected by the scientific characterisation and analysis of defect structures and the definition of suitable test parts and test procedures. Moreover the necessary sensor requirements and software requirements have been determined and the concept of the experimental set-up has been elaborated. Therefore only a few dissemination activities have taken place in the first half of the project.
For the second period of the project a large number of dissemination activities have been scheduled and performed. With the ongoing development, the project results could have been presented on trade fairs, in papers and in workshops continuously.

A large number of dissemination activities have been realized during the project and several more are already targeted for the future like the Control 2015, the largest trade fair for Quality Control and NDT in Germany and probably Europe.
Disseminating the results to a wide range of public interest groups has helped the project’s consortium to verfify and improve the quality of the results continuously during the project.

List of Websites:
www.qualifibre.eu

contact coordinator:
Fraunhofer IPA
Ms. Ira Effenberger
email: ira.effenberger@ipa.fraunhofer.de

Final Report Summary - QUALIFIBRE (Qualification and Diagnosis of Carbon and Glass Fibre-Reinforced Composites with Non-Destructive Measurement Technologies)

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