Effect of weathering on the stress distribution and mechanical performance of automotive paint systems

1998 ◽  
Vol 70 (10) ◽  
pp. 141-149 ◽  
Author(s):  
M. E. Nichols ◽  
C. A. Darr
Keyword(s):  
Stress Distribution ◽  
Mechanical Performance ◽  
Paint Systems ◽  
Automotive Paint

The effects of weathering on the mechanical performance of automotive paint systems

1999 ◽  
Vol 35 (1-4) ◽  
pp. 153-159 ◽  
Author(s):  
M.E. Nichols ◽  
J.L. Gerlock ◽  
C.A. Smith ◽  
C.A. Darr
Keyword(s):  
Mechanical Performance ◽  
Paint Systems ◽  
Automotive Paint

Effect of the frictional coefficient and pre-tension on stress distribution of fabric during the weaving process

2017 ◽  
Vol 88 (8) ◽  
pp. 904-912
Author(s):  
Zhiping Ying ◽  
Zhenyu Wu ◽  
Xudong Hu ◽  
Xiangqing Zhou
Keyword(s):  
Numerical Model ◽  
Stress Distribution ◽  
Mechanical Performance ◽  
Frictional Coefficient ◽  
Woven Fabric ◽  
Weft Yarn ◽  
Tension Stress ◽  
Initial Shape ◽  
Warp Tension ◽  
Fluctuation Range

The non-uniform stress distribution of woven fabric has a significant influence not only on its mechanical performance in service, but also on its weaving efficiency in the fabrication process. For investigating the stress distribution in woven fabric, a numerical model at the yarn scale was established to simulate the interlacing process between the weft and warp yarns using an explicit finite element solver. The yarns were assumed to be a homogeneous continuum and the transversal isotropic constitutive equation was used. A modified lenticular initial shape was used as the cross-section of the yarn and trajectories of warp and weft yarns were set to be straight. The classical Amonton–Coulomb law was used for the tangential behavior between the weft and warp yarns. The simulation results reveal that the interaction between weft and warp yarns consists of three phases in terms of contact, adhesion and sliding. The sectional stress distribution in the weft yarn determined by multi-points contact between a single weft yarn and a group of warp yarns was also analyzed. The tension stress of the weft yarn was larger in the middle part than that in both sides. Based on the numerical model, the effects of two key parameters, namely the frictional coefficient and weft pre-tension, on the stress distribution were discussed in detail. The weft crimp angle and warp tension distribution uniformity decreased as the frictional coefficient decreased, whereas the warp tension fluctuation range did not obviously decrease. However, an improved method by exerting pre-tension in two ends of weft yarn was proposed and the warp tension fluctuation range was significantly decreased. The distribution trend of warp tension obtained from the numerical simulation showed an acceptable tendency with experiment measurements.

Stress Analysis under Cu Bump Bonding Process

2012 ◽  
Vol 217-219 ◽  
pp. 2317-2321 ◽  
Author(s):  
Chun Yue Huang ◽  
Ying Liang ◽  
Song Wu ◽  
Tian Ming Li
Keyword(s):  
Stress Distribution ◽  
Flip Chip ◽  
Mechanical Performance ◽  
Copper Wire ◽  
Low Cost ◽  
Element Model ◽  
Bonding Process ◽  
Bonding Pressure ◽  
Shaping Process ◽  
Set Up

The copper wire has some advantages in thermal performance, mechanical performance, and low cost, which make it can provide the lowest cost flip-chip(FC) package for low I/O density device. The 2D Cu stud bump finite element model was set up by using ANSYS/LS-DYNA with LOLID162 element to dynamic simulate the Cu stud bump bonding shaping process. The stress distribution in the Cu stud bump and the pad during the bonding process were studied, and the influence of pad thickness on the stress distribution of Si chip was also analyzed. The results shows that under the bonding process the Cu bump height is mainly influenced by the bonding pressure and the top shape of the Cu bump is influenced by ultrasonic energy, the increase of pad thickness results in reducing stress concentration inside the Si chip.

scholarly journals Library Search Prefilters for Vehicle Manufacturers to Assist in the Forensic Examination of Automotive Paints

2017 ◽  
Vol 72 (3) ◽  
pp. 476-488 ◽  
Author(s):  
Barry K. Lavine ◽  
Collin G. White ◽  
Tao Ding
Keyword(s):  
Pattern Recognition ◽  
Ir Spectra ◽  
General Motors ◽  
Discrete Wavelet ◽  
Vehicle Manufacturer ◽  
Clear Coat ◽  
Discrimination Power ◽  
Paint Systems ◽  
Automotive Paint ◽  
Spectral Libraries

Pattern recognition techniques have been applied to the infrared (IR) spectral libraries of the Paint Data Query (PDQ) database to differentiate between nonidentical but similar IR spectra of automotive paints. To tackle the problem of library searching, search prefilters were developed to identify the vehicle make from IR spectra of the clear coat, surfacer–primer, and e-coat layers. To develop these search prefilters with the appropriate degree of accuracy, IR spectra from the PDQ database were preprocessed using the discrete wavelet transform to enhance subtle but significant features in the IR spectral data. Wavelet coefficients characteristic of vehicle make were identified using a genetic algorithm for pattern recognition and feature selection. Search prefilters to identify automotive manufacturer through IR spectra obtained from a paint chip recovered at a crime scene were developed using 1596 original manufacturer’s paint systems spanning six makes (General Motors, Chrysler, Ford, Honda, Nissan, and Toyota) within a limited production year range (2000–2006). Search prefilters for vehicle manufacturer that were developed as part of this study were successfully validated using IR spectra obtained directly from the PDQ database. Information obtained from these search prefilters can serve to quantify the discrimination power of original automotive paint encountered in casework and further efforts to succinctly communicate trace evidential significance to the courts.

Lightweight Design of a Multi-Material Suspension Lower Control Arm

2020 ◽  
Author(s):  
Alessandro Messana ◽  
Lorenzo Sisca ◽  
Alessandro Ferraris ◽  
Andrea Giancarlo Airale ◽  
Massimiliana Carello
Keyword(s):  
Carbon Fiber ◽  
Stress Distribution ◽  
Carbon Fibre ◽  
Mechanical Performance ◽  
Lightweight Design ◽  
Design Analysis ◽  
Hybrid Technology ◽  
Mechanical Coupling ◽  
Lower Control Arm

Abstract This paper is focused on the design, analysis and testing of a multi-material (carbon fibre and steel) Lower Control Arm (LCA) of a McPherson suspension for a C segment vehicle. Therefore, starting from the existing component (made of steel), the LCA mass has been reduced by using a hybrid technology, diminishing the steel thickness and adding a carbon fiber tailored cover without compromising the mechanical performance in terms of stiffness and stress distribution. In so doing, it has been possible to evaluate the potential and the capabilities of the hybridization without re-designing the component totally. In particular, it has been developed a specific methodology that combines both virtual and experimental procedures to face the hybridization challenges of mechanical coupling, safety and lightweight. For these reasons, the multi-material lower control arm represents a noticeable case study in which this methodology has been applied, correlated and validated.

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