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The 12 papers in this techncial paper collection represent research in the areas of welding, riveting, joining, and fastening for automotive applications. Papers focus on the recent advances in the process optimization, analytical solution, numerical modeling, response evaluation as well as static and dynamic testing of traditional resistance spot welds, gas metal arc welds, friction stir spot welds, laser welds, rivets, mounts, adhesives, and fasteners.

Optical fiber has begun replacing copper in avionic networks. So far, however, it has been mainly restricted to non-critical applications (video transmission to the flight deck, IFE?). In order to take advantage of the high-bandwidth, low weight, no EMI properties of optical fibers in all data transmission networks, it will be necessary to improve the testing. One part of the puzzle, which is still missing, is the self-test button: the possibility to check the network and detect potential failures before they occur. The typical testing tool of a technician involved in optical fiber cables is the ?light source ? optical power meter? pair. With this tool, one can measure the insertion loss of the fiber link. A second important parameter, the return loss at each optical connector, is not analysed. In addition, this is only a global measurement, which does not allow the detection of possible weak points.

This article characterizes the special features of drilling of CFRP/Titanium and -Aluminium stacks. Simplified theoretic models will show how CFRP/Titanium stacks should be machined without scratches and burn marks contacting carbon. Low axial forces and smart chip removal technology are the main characteristics of the drilling tool technology, optimized to reach H8 quality in one shot operation. Presenter Peter Mueller-Hummel, Cutting Tools Inc.

A significant step is achieved on the flight control actuation system toward the more electrical aircraft through the Airbus A380, A400M and the A350 development phase ongoing. The A380/A400M/A350 features a mixed flight control actuation power source distribution, associating electrically powered actuators with conventional FlyByWire hydraulic servocontrols. In the scope of the preparation of the future Airbus Aircraft, this paper presents the perspectives of the use of the EMA technologies for the flight control systems in the more electrical aircraft highlighting the main technical challenges need to treat: jamming susceptibility, ?on board? maintenance reduction, Operational reliability increase, power electronics and power management optimization, and regarding the environmental constraints, the predicted performances; the benefits associated to the optimized utilization of on-board power sources.

Exatec� PC glazing technology team, has developed advanced weathering and abrasion resistant coatings technology that can be applied to protect polycarbonate. It is of particular interest to quantify and understand the factors that determine the surface abrasion performance of coated PC in rear window and backlight applications that have a wiper system. In the present study we describe Exatec's lab scale wiper testing equipment and test protocols. We also describe adaptation of optical imaging system to measure contrast and nano-profiling using nano-indenter, as post wiper surface characterization methods. These methods are more sensitive to fine scratches on glazing surface than standard haze measurement and mechanical profilometry. Three coating systems were investigated; Siloxane wetcoat (A), Siloxane wetcoat (B), and Siloxane wetcoat (B) plus plasma coat (Exatec� E900 coating). The performance comparisons were made using all these surface characterization methods.

General research in the areas of welding, riveting, joining, and fastening for automotive applications is discussed in the 9 papers in this technical paper collection. Topics include process optimization, analytical solution, numerical modeling, response evaluation as well as static and dynamic testing of traditional resistance spot welds, gas metal arc welds, friction stir spot welds, laser welds, rivets, mounts, adhesives, and fasteners.

The 9 papers in this technical paper collection focus on welding, joining and fastening for automotive applications. Topics covered include adhesively bonded joints, Battelle Structural Stress method, friction stir spot welding, and more. The 9 papers in this technical paper collection focus on welding, joining and fastening for automotive applications. Topics covered include adhesively bonded joints, Battelle Structural Stress method, friction stir spot welding, and more.

This technical paper collection discusses optical techniques; digital correlation; holography; shearography; nondestructive testing.

This technical paper collection includes papers related to welding and joining of similar or dissimilar materials of plastics, composites, aluminum, magnesium, titanium, and conventional and advanced high strength steels. Papers related to friction stir (spot) welding, ultrasonic welding, resistance welding, arc welding, laser welding, brazing or soldering, riveting and bolting, and adhesive joining, strength, fracture and fatigue of welds, joints and fasteners are covered.

Abstract Real-time reconstruction of 3D environment attributed with semantic information is significant for a variety of applications, such as obstacle detection, traffic scene comprehension and autonomous navigation. The current approaches to achieve it are mainly using stereo vision, Structure from Motion (SfM) or mobile LiDAR sensors. Each of these approaches has its own limitation, stereo vision has high computational cost, SfM needs accurate calibration between a sequences of images, and the onboard LiDAR sensor can only provide sparse points without color information. This paper describes a novel method for traffic scene semantic segmentation by combining sparse LiDAR point cloud (e.g. from Velodyne scans), with monocular color image. The key novelty of the method is the semantic coupling of stereoscopic point cloud with color lattice from camera image labelled through a Convolutional Neural Network (CNN).

Abstract In this paper, an efficient lane detection using deep feature extraction method is proposed to achieve real-time lane detection in diverse road environment. The method contains three main stages: 1) pre-processing, 2) deep lane feature extraction and 3) lane fitting. In pre-processing stage, the inverse perspective mapping (IPM) is used to obtain a bird's eye view of the road image, and then an edge image is generated using the canny operator. In deep lane feature extraction stage, an advanced lane extraction method is proposed. Firstly, line segment detector (LSD) is applied to achieve the fast line segment detection in the IPM image. After that, a proposed adaptive lane clustering algorithm is employed to gather the adjacent line segments generated by the LSD method. Finally, a proposed local gray value maximum cascaded spatial correlation filter (GMSF) algorithm is used to extract the target lane lines among the multiple lines.

Abstract The dynamic characteristics of tires are critical in the overall vibrations of vehicles because the tire-road interface is the only medium of energy transfer between the vehicle and the road surface. Obtaining the natural frequencies and mode shapes of the tire helps in improving the comfort of the passengers. The vibrational characteristics of structures are usually obtained by performing conventional impact hammer modal testing, in which the structure is excited with an impact hammer and the response of the structure under excitation is captured using accelerometers. However, this approach only provides the response of the structure at a few discrete locations, and it is challenging to use this procedure for rotating structures. Digital Image Correlation (DIC) helps in overcoming these challenges by providing the full-field response of the structure.

Abstract The Friction stir welding (FSW) is recently presented so to join different materials without the melting process as a solid-state joining technique. A widely application for the FSW process is recently developed in automotive industries. To create the welded components by using the FSW, the plunged probe and shoulder as welding tools are used. The Finite Element Method (FEM) can be used so to simulate and analyze material flow during the FSW process. As a result, thermal and mechanical stresses on the workpiece and welding tool can be analyzed and decreased. Effects of the welding process parameters such as tool rotational speed, welding speed, tool tilt angle, depth of the welding tool, and tool shoulder diameter can be analyzed and optimized so to increase the efficiency of the production process. Material characteristics of welded parts such as hardness or grain size can be analyzed so to increase the quality of part production.

Abstract The present study aims to join the dissimilar materials such as Dual-Phase (DP) 600 Steel and AA6082-T6 Aluminum (Al) alloy via the friction stir welding (FSW) process with a reduced intermetallic compound (IMC) layer. The five different tool tilt angles of 0°, 0.5°, 1°, 1.5°, and 2° were selected to fabricate the joints. The weld characteristics such as tensile strength, hardness, macrostructure, and microstructure were analyzed. The weld interface was studied by employing an optical microscope and scanning electron microscope (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) techniques. The joint produced with a 0.5° tilt angle has achieved the highest ultimate tensile strength (UTS) of 240 MPa. The IMCs were identified as Fe2Al8 and FeAl2 from the joint interface studies.

Abstract Vaporizing foil actuator welding (VFAW) created nominally solid-state spot welds between high-strength DP980 steel and 6022 T4 aluminum. The effects of varying the impact velocity and angle between the Al flyer and target steel sheets on the structure and properties of the joints were evaluated using photonic Doppler velocimetry (PDV), scanning electron microscopy (SEM), fractography, and energy-dispersive spectroscopy (EDS) analysis. The incident angle and velocity of the flyer plate were quantified using PDV, and their relations to the structure and properties of the joint were assessed with microscopy and strength testing. Impact velocity and average impact angle increase with the increasing standoff. Lower impact angles and higher impact velocities promoted interfacial failure due to increased melting, higher intermetallic thickness, and lower wave amplitude and wavelength.

Abstract Direct welding of coated steels to aluminum alloys is challenging due to high energy requirements, decreased weldability, and unstable weld quality. The present study reports the application of a new design approach in vaporizing foil actuator welding (VFAW), where an asymmetric preform shape on the target sheet generated the requisite standoff, enabling direct spot welding of a typical automotive aluminum alloy (6022 T4) and two different zinc-coated steels, galvanized high-strength low-alloy 350 and galvannealed dual-phase 590. The use of the new approach enabled for the first time the ability to spot weld through coating without any preweld surface preparation. Characterization using lap-shear and peel testing revealed strong joints for both the weld pairs (AA 6022 T4-HSLA 350 and AA 6022 T4-DP 590). The weld interface characterized by scanning electron microscopy (SEM) revealed a hierarchical structure and the presence of a typical wavy region.

Abstract The causes of failure due to cracking in the resistance spot welding of the advanced high-strength steels dual-phase 590 (DP590) were investigated using scanning electron microscopy (SEM), optical microscopy, and the tensile-shear test. The results showed that by increasing the current amount, the formation of the melting zone occurred in the heat-affected zone, leading to the cracking in this area, reducing the tensile strength and decreasing the mechanical properties; the initiation and growth of cracking and failure in this region also happened. In the heat-affected zone, by increasing the current amount with the softening phenomenon, the recrystallized coarse grains also occurred, eventually resulting in the loss of mechanical properties. The results of the tensile-shear test also indicated that by increasing the current up to 12 kA, the strength was raised, but the ductility was reduced.

Abstract Sound ductile iron (DI) welded joints were performed using developed coated electrode and optimized welding parameters including post weld heat treatment (PWHT).Weldments consisting of weld metal, partially melted zone (PMZ), heat affected zone (HAZ) and base metal were austenitized at 900 °C for 2 hour and austempered at 300 °C and 350 °C for three different holding time (1.5 hour, 2 hour and 2.5 hour). In as-weld condition, microstructures of weld metal and PMZ show ledeburitic carbide and alloyed pearlite, but differ with their amount. Whereas microstructure of HAZ shows pearlite with some ledeburitic carbide and base metal shows only ferrite.

Abstract New analytical structural stress solutions for a rigid inclusion in a finite square thin plate with clamping edges under opening loading conditions are developed. The new solutions are used to derive new analytical structural stress and stress intensity factor solutions for similar and dissimilar spot welds in cross-tension specimens. Three-dimensional finite element analyses are conducted to obtain the stress intensity factor solutions for similar spot welds and dissimilar magnesium/steel spot welds in cross-tension specimens of equal thickness with different ratios of half-specimen width-to-weld radius. A comparison of the analytical and computational solutions indicates that the analytical stress intensity factor solutions for similar spot welds in cross-tension specimens of equal thickness are accurate for large ratios of half-specimen width-to-weld radius.

Abstract The use of Abrasive Water Jet (AWJ) cutting technology can improve the edge stretchability in sheet metal forming. The advances in technology have allowed significant increases in working speeds and pressures, reducing the AWJ operation cost. The main objective of this work was to determine the effect of selected AWJ cutting parameters on the Hole Expansion Ratio (HER) for a DP800 (Dual-Phase) Advanced High-Strength Steel (AHSS) with s0 = 1.2 mm by using a fractional factorial design of experiments for the Hole Expansion Tests (HET). Additionally, the surface roughness and residual stresses were measured on the holes looking for a possible relation between them and the measured HER. A deep drawing quality steel DC06 with s0 = 1.0 mm was used for reference. The fracture occurrence was captured by high-speed cameras and by Acoustic Emissions (AE) in order to compare both methods.