Validering av VTI-PFT version 4 : mätningar på plana och profilerade vägmarkeringar

This study shows that the PFT (Portable Friction Tester) in its fourth version, featuring an improved mechanical design with a new measurement tire, similar to previous versions, is a user friendly and robust method with excellent reproducibility. The results indicate very low variation between individual instruments and an almost negligible influence by the operator. Correlation studies with the SRT pendulum on plane road markings were conducted using a set of different road markings commonly used in Sweden of varying age and quality. Results indicate a linear relationship according to the following: SRT = 78.6*PFT + 9.2 ± 9.0 A correlation study using two individual PFT instruments with different operators on a set of commonly used profiled road markings in Sweden showed an excellent repeatability and a dynamic measurement range similar to plane road markings. The results clearly indicate that the PFT is suitable to use as a stand-alone method for objective assessment of skid resistance of plane as well as of profiled road markings, thus eliminating the need of the SRT pendulum

Automated monitoring of groundwater contamination along salted roads

This report describes the results from preliminary laboratory investigations of ground water samples obtained during the autumn of 2004 from national road 67 Heby in Sweden, using a novel liquid sensor technology, "Electronic Tongue" (ET), and a commercial conductivity probe. Partial least squares regression (PLS) combined with principal component analysis (PCA) was used to build a model to quantify ET data using ion concentrations determined by conventional laboratory analysis as well as measured conductivity data. Results showed very good correlation between ET data and chlorine concentrations in field samples as well as conductivity data. In addition to chlorine concentration, results also indicated that ET has the potential to detect and warn for other types of contaminants in ground water. The reports also describes the planned installation in June 2005 of a complete system for remote monitoring of chloride concentration via the Internet using a similar technology platform as for the VTI frost monitoring system (Tjäl 2000)

Growth of TiC/a-C:H nanocomposite films by reactive high power impulse magnetron sputtering under industrial conditions Growth of Ti-C nanocomposite films by reactive high power impulse magnetron sputtering under industrial conditions

Abstract Titanium carbide (TiC) films were deposited employing high power impulse magnetron sputtering (HiPIMS) and direct current magnetron sputtering (DCMS) in an Ar-C 2 H 2 atmosphere of various compositions. Analysis of the structural, bonding and compositional characteristics revealed that the deposited films are either TiC and hydrogenated amorphous carbon (a-C:H) nanocomposites, nanocrystalline TiC, or Ti/TiC, depending on the C/Ti ratio. It was found that Ti-C films grown by HiPIMS show a C/Ti ratio of close to 1 for a wide C 2 H 2 flow range (4-15 sccm), with free C ranging from 0 to 20%. Thus, films ranging from near stoichiometric single phase TiC to TiC/a-C:H nanocomposites can be synthesized. This was not the case for DCMS, where films grown using similar deposition rates as for HiPIMS *Manuscript Click here to view linked References 2 formed larger fractions of amorphous C matrix, thus being nanocomposites in the same C 2 H 2 (above 4 sccm) flow range. For a C/Ti ratio of 1 the resistivity is low (4-8×10 2 µΩcm) for the HiPIMS films, and high (>100×10 2 µΩcm) for the DCMS films. The hardness also shows a big difference with 20-27 and 6-10 GPa for HiPIMS and DCMS grown films, respectively

Growth of TiC/a-C:H nanocomposite films by reactive high power impulse magnetron sputtering under industrial conditions

Titanium carbide (TiC) films were deposited employing high power impulse magnetron sputtering (HiPIMS) and direct current magnetron sputtering (DCMS) in an Ar-C2H2 atmosphere of various compositions. Analysis of the structural, bonding and compositional characteristics revealed that the deposited films are nanocomposites; either hydrogenated amorphous carbon and TiC (TiC/a-C:H), or Titanium and TiC (Ti/TiC) depending on the C/Ti ratio of the films. It was found that TiC/a-C:H films grown by HiPIMS were dense, and within a certain C2H2 flow range (4-15 sccm) showed little changes in C/Ti ratio, which also saturated towards 1. The HiPIMS grown films also exhibited the tendency to form smaller fractions of amorphous C matrix, and incorporate smaller amounts of oxygen contaminants, as compared to films grown by DCMS. The TiC/a-C:H films exhibited resistivity and hardness values of 4-8×102 μΩcm and 20-27 GPa, respectively when deposited by HiPIMS. The corresponding values for films grown by DCMS at the same deposition rate as HiPIMS were &gt;10×102 μΩcm and ~6-10 GPa respectively, likely due to abundant formation of free C and porosity, allowing oxygen contaminations.funding agencies|Swedish Research Council (VR)| 621-2005-3245 621-2008-3222 623-2009-7348 |</p

Influence of ionization degree on film properties when using high power impulse magnetron sputtering

Chromium thin films are deposited by combining direct current magnetron sputtering and high power impulse magnetron sputtering (HiPIMS) on a single cathode in an industrial deposition system. While maintaining a constant deposition rate and unchanged metal ion energy distribution function, the fraction of the total power supplied by either deposition technique is altered, and thereby also the metal ion to metal neutral ratio of the deposition flux. It is observed that the required total average power needed to be proportionally increased as the HiPIMS fraction is increased to be able to keep a constant deposition rate. The influence on microstructure, electrical, and electrochemical properties of the films is investigated and shows improvements with the use of HiPIMS. However, considerable influence of the studied properties occurs already when only some 40% of the total power is supplied by the HiPIMS technique. Further increase of the HiPIMS power fraction results in comparatively minor influence of the studied properties yet significant deposition rate efficiency reduction. The results show that the degree of ionization can be controlled separately, and that the advantages associated with using HiPIMS can be obtained while much of the deposition rate reduction, often reported for HiPIMS, can be avoided.Funding Agencies|Swedish Research Council (VR)|621-2005-3245621-2008-3222623-2009-7348|Swedish Foundation for Strategic Research||</p

Growth of TiC/a-C:H nanocomposite films by reactive high power impulse magnetron sputtering under industrial conditions

Titanium carbide (TiC) films were deposited employing high power impulse magnetron sputtering (HiPIMS) and direct current magnetron sputtering (DCMS) in an Ar-C2H2 atmosphere of various compositions. Analysis of the structural, bonding and compositional characteristics revealed that the deposited films are nanocomposites; either hydrogenated amorphous carbon and TiC (TiC/a-C:H), or Titanium and TiC (Ti/TiC) depending on the C/Ti ratio of the films. It was found that TiC/a-C:H films grown by HiPIMS were dense, and within a certain C2H2 flow range (4-15 sccm) showed little changes in C/Ti ratio, which also saturated towards 1. The HiPIMS grown films also exhibited the tendency to form smaller fractions of amorphous C matrix, and incorporate smaller amounts of oxygen contaminants, as compared to films grown by DCMS. The TiC/a-C:H films exhibited resistivity and hardness values of 4-8×102 μΩcm and 20-27 GPa, respectively when deposited by HiPIMS. The corresponding values for films grown by DCMS at the same deposition rate as HiPIMS were &gt;10×102 μΩcm and ~6-10 GPa respectively, likely due to abundant formation of free C and porosity, allowing oxygen contaminations.funding agencies|Swedish Research Council (VR)| 621-2005-3245 621-2008-3222 623-2009-7348 |</p