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Plasma technologies at atmospheric pressure (AP) promise efficient integration into industrial manufacturing technology and save considerable investment and maintenance costs. The development of new fields of application of AP techniques increasingly requires the provision of adapted, large‐area plasma sources. The linearly extended direct current (DC) arc plasma source, long arc generator principle (LARGE) for short, with a working width of up to 350 mm was developed at the Fraunhofer IWS for the large area plasma surface treatment. In contrast to other jet‐based AP sources arrays, the LARGE plasma source has a very long afterglow flame length, which makes it possible to efficiently treat surfaces over the range ±40 mm. Especially for large‐area plasma applications, commercial jet nozzle arrays are very complex to control and require more than one power generators which increases the equipment cost. In this paper we discuss selected application fields, namely the rapid (up to 50 m/min) removal of oil films on aluminium sheets, the large‐area functionalization (removal of release agents) of carbon‐fibre reinforced plastic (CFRP) materials, and the deposition of SiO2 adhesive layers on titanium to improve adhesion in the structural bonding of these materials.

Within the Dutch standards laboratory (NMi Van Swinden Laboratorium) a traceable atomic force microscope (AFM) is currently being developed where we aim at a measurement uncertainty of 1 nm. As part of this development novel methods have been developed for the calibration of this instrument. The SPM has been constructed using a commercial AFM head that has been embedded in a metrology frame using an accurate 3D translation stage. The position of the AFM probe relative to the sample is determined along three orthogonal measurement axes by three individual laser interferometers. Due to the properties of the 3D translation stage the Abbe offset between the probe position and the measurement axes should remain below 0.1 mm in order to realize an overall measurement uncertainty of 1 nm. Since the laser interferometers use a four-pass optical configuration the measurement axis is defined by the virtual centre of the four positions of the laserspots onto the plane retro mirror. In order to accurately determine this virtual centre and therefore the position of the measurement axis a device has been designed to measure the four laserspot positions of each axis within the SPM. Since the AFM probe position is determined in 3D accurate calibration of the angles between the measurement axes is important if the measurement error is to be minimized to 1 nm. Different calibration setups to accurately determine these angles will be presented. Additionally, a method for the alignment of the optical axes of the laser interferometers with respect to the end mirrors of the interferometers will be discussed. In order to calculate the overall measurement uncertainty of the scanning probe microscope we decided to use the virtual measurement machine concept since a purely analytical approach for these types of measurement instruments is nearly impossible (Schwenke et al 2000 Ann. CIRP 49 395–8). The model or virtual SPM that has been developed for the simulation of the instrumental characteristics will be presented.

In the latest generation of aircraft new light-weight design concepts are highly in demand. The material development in the aerospace industry shows a clear trend. More than 50 % of the structure of an Airbus A350 XWB and a Boeing 787 are made of carbon fiber reinforced plastic (CFRP), while the Airbus A300 had only a share of 7 % CFRP in the 1970's. The increasing amount of composite materials leads to problematic material combinations. Carbon fiber reinforce plastics can induce galvanic corrosion when attached to an aluminum structure. To overcome this phenomenon titanium alloys are used. To date, the most widely used joining technique is riveting. However, this is disadvantageous due to the high notch sensitivity, the low shear strengths and bearing stress of CFRP. To overcome these limitations, adhesive bonding can be applied. However long-term stable adhesion on Titanium is still an issue and the key to success is to realize a suitable surface treatment. Currently used pre-treatments of titanium joints are mostly wet-chemical bath processes, which often comprise hazardous chemicals, whereas manual process grinding is the mainly used pre-treatment for CFRP. Plasma enhanced chemical vapor deposition (PECVD) at atmospheric pressure seems to be an alternative to these methods to overcome environmental issues and increase the repeatability on composite materials.

This paper focuses on the on the design and calibration of an elastically guided vertical axis that will be applied in a small high precision 3D Coordinate Measuring Machine aiming a volumetric uncertainty of 25 nm. The design part of this paper discusses the principles of this system, the compensation of the stiffness of the vertical axis in the direction of motion, the weight compensation method and the design and performance of the axis precision drive system, a Lorentz actuator. In the metrology part of this paper the calibration methods to determine the linearity as well as motion straightness and axis rotation errors are discussed. Finally first calibration results of this axis show nanometer repeatability of the probing point over the 4 mm stroke of this axis. The causes of the short-term variations with a bandwidth of about ± 10 nm are under investigation. Error compensation may reduce the residual error of the probing point to the nanometer level.

A commercially available carbon fiber (CF) with an epoxy-based sizing (EP-sized CF) and an unsized CF have been plasma treated to study the effect on the fiber-matrix adhesion towards a polypropylene matrix. The EP-sized fiber was chosen because of its predictable low adhesion in a polypropylene (PP) matrix. The fibers have been modified using a microwave low-pressure O2/CO2/N2-gas plasma source (Cyrannus®) developed at IWS in a batch process. One aim of this study was the evaluation of parameters using high energies and short time periods in the plasma chamber to see the effect on mechanical performance of CF. These results will be the fundamental work for a planned continuous plasma modification line. The CF surface was characterized by determining the surface energies, single fiber tensile strength and XPS analysis. The adhesion behavior before and after plasma treatment was studied by single fiber pull-out test (SFPO) and scanning electron microscopy (SEM). It was shown that the CO2- and O2-plasma increases the number of functional groups on the fiber surface during short time plasma treatment of 30 s. Carboxylic groups on the unsized CF surface resulting from O2-plasma treatment lead to an enhanced fiber-matrix adhesion, whereas the fiber strength was merely reduced.

This paper evaluates wet-chemical pre-treatments (alkaline etching, anodising) and a plasma treatment for structural bonding of titanium (Ti6Al4V). The main objective of this study is the comparison of the applicability of the plasma pre-treatment to wet-chemical treatments on titanium for structural bonding. In this context, an atmospheric pressure plasma device was used to deposit thin functional films from hexamethyldisiloxane (HMDSO) precursor on titanium. X-ray photoelectron spectroscopy (XPS) was employed to assess the chemical composition of the surface after different pre-treatments on the titanium substrate, while the morphology and the film thickness were investigated with scanning electron microscopy (SEM). The adhesion properties on titanium were evaluated by means of a wedge test in hot/wet conditions. After bonding tests the fracture surface and the failure loci were analysed. Using a long arc plasma generator and HMDSO precursor almost stoichiometric SiO2 coatings were obtained on the titanium substrate. These coatings exhibit good long-term durability and bond strength compared to an alkaline etching in the wedge test. The investigated anodising process leads to oxide layers revealing a highly porous nanostructure. In contrast to the alkaline etching, the plasma derived coatings and the oxide layer produced by the anodising process exhibit a higher micro, respectively nano roughness, and hence a better long-term durability.

We have investigated the uncertainty sources that affect the traceability of dimensional measurements using the VIScan of the Zeiss F25 coordinate measuring machine (CMM). Our experimental results on line-width measurements are promising, having a repeatability below 120 nm and moreover they are reproducible for all light settings investigated. The comparison with the measurements performed on a facility used for line-scale calibrations provides very good agreement. At present we can report an uncertainty below 0.45 μm for line-width calibrations. This would be the first traceable F25 VIScan, and to our knowledge one of the first truly traceable vision systems for line-width calibrations.

This paper focuses on the on the design and calibration of an elastically guided vertical axis that will be applied in a small high precision 3D Coordinate Measuring Machine aiming a volumetric uncertainty of 25 nm. The design part of this paper discusses the principles of this system, the compensation of the stiffness of the vertical axis in the direction of motion, the weight compensation method and the design and performance of the axis precision drive system, a Lorentz actuator. In the metrology part of this paper the calibration methods to determine the linearity as well as motion straightness and axis rotation errors are discussed. Finally first calibration results of this axis show nanometer repeatability of the probing point over the 4 mm stroke of this axis. The causes of the short-term variations with a bandwidth of about ± 10 nm are under investigation. Error compensation may reduce the residual error of the probing point to the nanometer level.

In the Netherlands, since September 1985 a statutory obligation exists for an annual examination of motor verhicles. Resulting from the Act a number of metrological activities with respect to the measuring instruments in use at the test stations are carried out by the Nether-lands Metrology Service, i.e. the examination and testing of new types of measuring instruments resulting in a “pattern approval”; the initial verification of newly installed instruments, i.e. individual examination, tests and calibration; reverification of particular instruments in use.