The advancing electrification of the powertrain is leading towards new challenges in the field of acoustics. Film capacitors used in power electronics are a potential source of high-frequency interfering noise since they are exposed to voltage harmonics. These voltage harmonics are caused by semiconductor switching operations that are necessary to convert the DC voltage of the battery into three-phase alternating current for the electrical machine. In order to predict the acoustic characteristics of the DC-link capacitor at an early stage of development, a multiphysical chain of effects has to be addressed to consider electrical and mechanical influences. In this paper, a new method to evaluate the excitation amplitude of film capacitor windings is presented. The corresponding amplitudes are calculated via an analytical force based on electromechanical couplings of the dielectric within film capacitors. As a next step, these calculated excitation amplitudes can be used in a FE simulation by applying volumetric strains on capacitor windings. This allows to consider the structural dynamic properties of different capacitor geometries. In order to lower the computational costs, a…

There is a crucial need of Electromagnetic interference shielding in many of the applications in this digital world with low cost and high efficient shielding materials. Electrically conducting heterocyclic polymer polypyrrole has found its application as an EMI shielding materials due to its conducting property. Electrically conducting polypyrrole (PPy) coated on coconut fibres (coir) with different morphology, were prepared through in-situ chemical polymerization of PPy using strong oxidizing agent like ammonium per sulfate. The synthesized PPy on coconut fibre were characterised using UV-Visible spectrophotometer(UV-VIS) and Fourier transform infrared spectroscopy (FTIR) which confirmed the product formation. The morphology was done using Scanning electron Microscopy(SEM).Thermal studies were performed by Thermo Gravimetric analysis (TGA). The effect of PPy morphology and content in composite with coir on the DC conductivity and shielding effectiveness (SE) were investigated. The shielding effectiveness was calculated theoretically and well matched with the experimental values.

High metallic silver colors using thin, smooth aluminum flake pigments are typically adopted for the luxury grades by each car manufacturer. Regarding the paint formulation for these types of colors, low non-volatile(N.V.) content and high aluminum flake pigment content are generally known to be necessary to achieve high metallic appearance designs. However, poor distribution of the aluminum flake pigments can cause mottling. In addition, a high concentration of aluminum flake pigments can result in a weak coating. Therefore, current paint systems are limited in the degree of high metallic appearance design that is possible. As a countermeasure to those problems, we investigated whether cellulose nanofiber (CNF) dispersion liquid can function as both the coating binder and rheology control agent in a new type of waterborne paint system. CNF is an effective rheology control agent because it forms strong hydrogen bonds with other fiber surfaces when it is dispersed for waterborne paint. For example, viscosity versus shear rate testing of an aqueous solution of 0.4wt% CNF and less than N.V. 5wt% showed a response curve similar…

The wet clutch system ( WCS ) is a complex combination of friction plates, separator plates and lubricant. The basic function of the WCS is to transfer torque under various operating conditions such as slipping, shifting, start/launch and/or torque converter clutch operation. During these conditions the slope of the coefficient of friction versus slip speed ( µ-V ) curve must be positive to prevent shudder of the WCS. A test procedure is needed to evaluate the WCS over a durability duty cycle to monitor the µ-V curve slope and shudder potential. The clutch plates and fluid must be tested together and remain together during the test to evaluate as a WCS. The objective of this paper is to describe this new test procedure which builds on the basics of the SAE J2964 - Low Speed Continuous Slip µ-PVT test procedure but a duty cycle is added to age the WCS. The test includes measurement of the µ-V slope at several intervals during the test ( before break in, after break in, and after each 12…

In order to achieve the Toyota Environmental Challenge of 2050, we have developed an innovative coating system that achieves 100% coating efficiency. In order to reduce paint loss in the painting process, it is necessary to eliminate overdust and bounce dust. The most important point is how to spray (atomization, particle flight, adhesion) without assist air. We have developed an “super high transfer efficiency system” that eliminates the need for assist air. We continue to challenge the development of innovative technologies to view the paint shop as clean and eco-friendly.

Aircraft components are commonly produced with 7000 series aluminum alloys (AA) due to its weight, strength, and fatigue properties. Auto Industry is also choosing more and more aluminum component for weight reduction. Current additive manufacturing (AM) methods fall short of successfully producing 7000 series AA due to the reflective nature of the material along with elements with low vaporization temperature. Moreover, lacking in ideal thermal control, print inherently defective products with such issues as poor surface finish alloying element loss and porosity. All these defects contribute to reduction of mechanical strength. By monitoring plasma with spectroscopic sensors, multiple information such as line intensity, standard deviation, plasma temperature or electron density, and by using different signal processing algorithm, AM defects have been detected and classified. For composition analysis, the ratio of the maximum intensities of Mg(I)/Al(I) shows a strong trend with the amount of Zn and Mg in the powder, and the results are extremely promising regarding the ability to use the online spectra for real time determination of the composition of the AA7075 powders with…

From the point of global and local environment, internal combustion engine is facing the need for significant improvement of exhaust emission. Especially, important is the reduction of unburned hydrocarbon (HC) from fuel film on liner under cold condition. In this study, at first, quantitative fuel film measurement technique by using Laser Induced Exciplex Fluorescence (LIEF) was developed. For the light source, 4th harmonic pulse yttrium aluminum garnet (YAG) laser (266nm) was used. For the tracer, the combination of N,N-Dimethylaniline (DMA) and naphthalene was used and quantitative concentration was decided by calibration test. With LIEF, the distribution of fuel film can be obtained by measuring the fluorescence only from the liquid phase. In order to evaluate the effect of fuel film on exhaust HC emission from engine, the film distribution was measured using quartz glass liner. For the injector, a prototype 6-hole gasoline injector was used. For the evaluation of total amount of fuel film on liner, the film distribution image was taken from both the exhaust and front side. The effect of fuel pressure (between…

With the introduction of stringent particulate number (PN) limit and real driving emission (RDE) requirements, gasoline particulate filters (GPFs) are widely adopted in Europe and China. GPF can be wash-coated with different level of three-way catalyst (TWC) coating. Some applications use heavy coating (>100g/L), and some don’t use at all. Pressure drop (DP) and PN filtration efficiency (FE) are the top two design criteria for OEMs. It is important to understand how various of coating technologies work with GPF technologies for optimized FE/DP performance. To study filter and coating interaction, a big matrix of coated GPFs are prepared and tested for lab DP and vehicle PN based FE. The matrix includes a wide range of wash coating loadings (WCLs), coating technologies that enable more coating inside GPF filtration walls (in-wall coating) or more on top of walls (on-wall coating), and GPF technologies with high and low mean pore size (MPS). Scanning electron microscope (SEM) is used to analyze microstructure of coated filter walls, and coating distribution for better understanding filter performance data. In general, DP…

Light-weight solutions for stamped steel components that exhibit the same or similar appearance properties for purposes of authentic feel and perception to customers will play a critical role as the goal of reaching maximum fuel efficiency for large vehicles continues. This paper outlines the potential uses for laminated steel or “MSC Smart Steel®” in large stamped steel bumpers that would normally be stamped with thick sheet metal in order to meet vehicle level functional objectives. The paper presents the investigation of the one for one drop in capabilities of MSC Smart Steel® material to existing stamping dies, special processing considerations while manufacturing, vehicle level performance comparisons, and class “A” coating options and process needs. Most of all, it will highlight the significant vehicle weight saving benefits and opportunities as compared to current production stamped steel bumpers.

This study assessed the interaction between sheet steel, lubricant and measurement system under typical sheet forming conditions. Deep Drawing Quality Bare, Electrogalvanized and Hot Dip Galvanized mild sheet steel, were tested under a Draw Bead Simulator (DBS). Lubricant conditions varied from thoroughly dry (0% lube) to overlubricated (>6 g/m2); with 1g of lubricant per m2 as the target of general usage. Mixed lubrication cases, with incremental amounts of a lubricant applied over an existing base of 1 g/m2 rust protection oil, were analyzed. The results show distinctive differences and similarities on friction between the bare material and the coatings. While friction on the bare substrate was higher than the coatings under lubricated conditions, it was significantly more tolerant to dry conditions. Stick-slip behavior was studied as a measurement system response to intermittent friction between the testing tools. These measurement test responses, and sheet surface texture changes during testing were discussed.